technical committee on heat recovery steam generators … · purging of hrsg/bypass stack. steve...

TECHNICAL COMMITTEE ON

HEAT RECOVERY STEAM GENERATORS NFPA 85

First Draft Meeting Agenda February 9, 2017 8:00 AM - 5:00 PM MT

Embassy Suites by Hilton Phoenix-Tempe, Tempe, AZ

1. Call to Order. Dwight Hyche, Chair

2. Introductions.

3. Approval of Meeting Minutes from August 10, 2016. (Attachment A)

4. Staff Updates. Laura Moreno, NFPA Staff

Committee membership update. (Attachment B)

Fall 2018 revision cycle schedule. (Attachment C)

Overview of NFPA Process

5. Review of Public Inputs: NFPA 85 Chapter 8 (Attachment D)

6. Review of Fundamentals Technical Committee actions (Attachment E). The committee members are asked to review the actions and bring forward any items warranting further discussion.

7. Task Group Reports.

Purging of HRSG/Bypass Stack. Steve Meierotto (chair), Don Bairley, and Randy Kleen.

8. New Business.

9. Next Meeting.

10. Adjourn.

NFPA 85 (BCS-HRS) Technical Committee First Draft Meeting Tempe, AZ - February 9, 2017

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Attachment A: Previous Meeting Minutes


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TECHNICAL COMMITTEE ON HEAT RECOVERY STEAM GENERATORS

NFPA 85 Pre-Draft Meeting Minutes

August 10, 2016 8:00 AM - 5:00 PM EDT NFPA Headquarters, Quincy, MA

Attendees:

Committee Members:

Dwight Hyche, Chair Swiss Re America Holding Corporation, MS

David Dexter* The Dow Chemical Company, LA

Fedja Drndarevic Technical Standards and Safety Authority, Canada

Martin Fry Coen Company, Inc., CA

Steven Graf* Emerson Process Management, PA

David Hinshaw* Dynegy, Inc., NY

David King* American Electric Power Corporation, OH

Randy Kleen General Electric Company, TX

David Leeper Burns & McDonnell, MO

Mark Loomer AECOM, NJ

Steven Meierotto Nooter Eriksen, MO

Windy Muehleisen* UTC/Forney Corporation, TX

Alan Robertson Sargent & Lundy, LLC, IL

Jimmie Schexnayder Entergy Corporation, LA


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Ilya Yarinovsky * Bechtel Corporation, MD

Donald Bairley General Electric Company, CT

Jennifer Beckmann Nooter Eriksen, MO

Karen Whitehead Black & Veatch Corporation, KS

Laura Montville, Staff Liaison National Fire Protection Association, MA

Guest:

Joseph Fehr Sega, Inc., KS

*Participated by teleconference

1. Call to Order. Dwight Hyche called the meeting to order at 8:00 a.m. and welcomed all committee members and guests.

2. Introductions. Committee members and guests introduced themselves and identified their affiliation.

3. Staff Updates. Laura Montville gave an overview of the Fall 2018 revision cycle schedule.

4. Task Group Reports.

Purging of HRSG/Bypass Stack. Steve Meierotto (chair), Don Bairley, and Randy Kleen.

o The task group was established at the Second Draft meeting in 2014 to perform a

complete review of 8.9.2, specifically to provide a recommendation on whether it is

necessary to include the combustion turbine fuel AIT in 8.9.2.2.2.2. This section was

revised by TIA 1136, which was incorporated into the 2015 edition of the code.

o The task group will develop language to clarify AIT requirements before the First Draft

Meeting.

5. Draft definitions and guidelines developed by the Correlating Committee and Fundamentals Committee. Laura Montville and Joseph Fehr explained the work of the Correlating Committee and the Fundamentals Technical Committee. These committees have identified terms that are not defined within the document and have asked the other Technical Committees to review and consider replacement with defined terms. The HRS Technical Committee reviewed usage of the several terms (interlock, trip, permissive, interlock system, safety interlock, trip device, interlock device, normal shutdown, and emergency shutdown) throughout Chapter 8 and the associated Annex material. Proposed revisions were developed, which will be submitted as Public Input before the closing date of


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January 5, 2017. See attachment for proposed revisions. The HRS Technical Committee noted that the Fundamentals Committee should not remove the definition of “combustion turbine normal shutdown” from Chapter 4 because it necessary to describe the term as used in Chapter 8.

6. Failed TIA 1194. The Technical Committee discussed the intent of sections 8.4.2.1.1.2, 8.4.2.1.2.2, 8.4.3.2.2.3, and 8.4.3.2.3.4, and came to the consensus that the sections currently reflect the intent of the committee with regards to safety shutoff valves. The committee invites public input if anyone disagrees and would like these sections to be revised in the next edition.

7. Technical questions. The Technical Committee discussed several topics that came to NFPA through Advisory Services or have been discussed by committee members at their places of employment.

8. New Business. No new business was discussed.

9. Next Meeting. The First Draft Meeting will be held on Thursday, February 9, 2017, and the location will be coordinated with the SBB and MBB committees.

10. Adjournment. The meeting adjourned at 12:42 p.m.


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Attachment B: Technical Committee Roster


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Address List No PhoneHeat Recovery Steam Generators BCS-HRS

Boiler Combustion System Hazards

Laura E. Moreno01/24/2017

BCS-HRS

Dwight G. Hyche

ChairSwiss Re America Holding Corporation1105 46th StreetMeridian, MS 39305-2749

I 3/1/2011BCS-HRS

John Burney

PrincipalProgress Energy299 1st Avenue North, PEF 902St. Petersburg, FL 33701

U 10/18/2011

BCS-HRS

David Paul Cannon

PrincipalHurst Technologies13514 Lakeside TerraceHouston, TX 77044

SE 1/17/1997BCS-HRS

David E. Dexter

PrincipalThe Dow Chemical CompanyPO Box 50Hahnville, LA 70057

U 8/9/2011

BCS-HRS

Fedja Drndarevic

PrincipalTechnical Standards and Safety Authority345 Carlingview DriveToronto, ON M9W 6N9 Canada

E 10/18/2011BCS-HRS

Dale P. Evely

PrincipalSouthern Company Services, Inc.42 Inverness Center Parkway(Bin B463)Birmingham, AL 35242-4809Alternate: Harrison B. Manning

U 10/10/1998

BCS-HRS

Martin Fry

PrincipalCoen Company, Inc.951 Mariners Island Blvd., Suite 410San Mateo, CA 94404

M 11/2/2006BCS-HRS

Steven V. Graf

PrincipalEmerson Process ManagementPower & Water Solutions200 Beta DrivePittsburgh, PA 15238-2918Alternate: Roy Reeves

M 8/5/2009

BCS-HRS

David J. Hinshaw

PrincipalDynegy, Inc.Independence Station76 Independence WayOswego, NY 13126

U 1/10/2008BCS-HRS

David W. King

PrincipalAmerican Electric Power Corporation1 Riverside PlazaColumbus, OH 43215

U 08/09/2012

BCS-HRS

Randy J. Kleen

PrincipalGeneral Electric CompanyGE Power and Water16415 Jacintoport BoulevardHouston, TX 77015-6589Alternate: Donald W. Bairley

M 7/26/2007BCS-HRS

David Leeper

PrincipalBurns & McDonnell9400 Ward ParkwayPO Box 419173Kansas City, MO 64141-6173

SE 08/17/2015

BCS-HRS

Mark S. Loomer

PrincipalAECOM510 Carnegie CenterPrinceton, NJ 08540-6241

SE 08/17/2015BCS-HRS

Steven A. Meierotto

PrincipalNooter Eriksen1509 Ocello DriveFenton, MO 63026-2406Alternate: Jennifer A. Beckmann

M 3/4/2008

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Address List No PhoneHeat Recovery Steam Generators BCS-HRS

Boiler Combustion System Hazards

Laura E. Moreno01/24/2017

BCS-HRS

Windy M. Muehleisen

PrincipalForney Corporation3405 Wiley Post RoadCarrollton, TX 75006

M 03/07/2013BCS-HRS

Alan R. Robertson

PrincipalSargent & Lundy, LLC55 East Monroe StreetChicago, IL 60603-5821

SE 08/17/2015

BCS-HRS

Jimmie J. Schexnayder

PrincipalEntergy Corporation1213 West 4th StreetKaplan, LA 70548Alternate: Ronald Rispoli

U 7/19/2002BCS-HRS

James P. Walawender

PrincipalBlack & Veatch Corporation11401 Lamar AvenueOverland Park, KS 66211-1508Alternate: Karen Whitehead

SE 10/3/2002

BCS-HRS

Ilya Yarinovsky

PrincipalBechtel Corporation5275 Westview DriveFrederick, MD 21703

SE 10/28/2008BCS-HRS

Humberto Gonzalez

Voting AlternateSiemens Energy Inc.4400 North Alafaya TrailMC Q2-286Orlando, FL 32826

M 08/11/2014

BCS-HRS

Donald W. Bairley

AlternateGeneral Electric175 Addison RoadPO Box 500Windsor, CT 06095Principal: Randy J. Kleen

M 1/1/1995BCS-HRS

Jennifer A. Beckmann

AlternateNooter Eriksen1509 Ocello DriveFenton, MO 63026-2406Principal: Steven A. Meierotto

M 08/17/2015

BCS-HRS

Harrison B. Manning

AlternateSouthern Company Services, Inc.42 Inverness Center Parkway(Bin B463)Birmingham, AL 35242Principal: Dale P. Evely

U 10/23/2013BCS-HRS

Roy Reeves

AlternateEmerson Process Management200 Beta DrivePittsburgh, PA 15238-2918Principal: Steven V. Graf

M 8/9/2011

BCS-HRS

Ronald Rispoli

AlternateEntergy Corporation2414 West 5th StreetRussellville, AR 72801-5541Principal: Jimmie J. Schexnayder

U 10/23/2003BCS-HRS

Karen Whitehead

AlternateBlack & Veatch Corporation11401 Lamar AvenueOverland Park, KS 66211Principal: James P. Walawender

SE 10/29/2012

BCS-HRS

Laura E. Moreno

Staff LiaisonNational Fire Protection Association1 Batterymarch ParkQuincy, MA 02169-7471

1/6/2015

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Attachment C: Fall 2018 Revision Cycle Schedule


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Fall 2018 Revision Cycle

Process Stage Process Step Dates for TCDates for TC

with CC

Public InputStage (First Draft)

Public Input Closing Date* 1/05/2017 1/05/2017

Final Date for TC First Draft Meeting 6/15/2017 3/16/2017

Posting of First Draft and TC Ballot 8/03/2017 4/27/2017

Final date for Receipt of TC First Draft ballot 8/24/2017 5/18/2017

Final date for Receipt of TC First Draft ballot - recirc 8/31/2017 5/25/2017

Posting of First Draft for CC Meeting 6/01/2017

Final date for CC First Draft Meeting 7/13/2017

Posting of First Draft and CC Ballot 8/03/2017

Final date for Receipt of CC First Draft ballot 8/24/2017

Final date for Receipt of CC First Draft ballot - recirc 8/31/2017

Post First Draft Report for Public Comment 9/07/2017 9/07/2017

Comment Stage(Second Draft)

Public Comment Closing Date* 11/16/2017 11/16/2017

Notice Published on Consent Standards (Standards that received no Comments)Note: Date varies and determined via TC ballot.

Appeal Closing Date for Consent Standards (Standards that received no Comments)

Final date for TC Second Draft Meeting 5/17/2018 2/08/2018

Posting of Second Draft and TC Ballot 6/28/2018 3/22/2018

Final date for Receipt of TC Second Draft ballot 7/19/2018 4/12/2018

Final date for receipt of TC Second Draft ballot - recirc 7/26/2018 4/19/2018

Posting of Second Draft for CC Meeting 4/26/2018

Final date for CC Second Draft Meeting 6/07/2018

Posting of Second Draft for CC Ballot 6/28/2018

Final date for Receipt of CC Second Draft ballot 7/19/2018

Final date for Receipt of CC Second Draft ballot - recirc 7/26/2018

Post Second Draft Report for NITMAM Review 8/02/2018 8/02/2018

Tech SessionPreparation (&

Issuance)

Notice of Intent to Make a Motion (NITMAM) Closing Date 8/30/2018 8/30/2018

Posting of Certified Amending Motions (CAMs) and Consent Standards 10/11/2018 10/11/2018

Appeal Closing Date for Consent Standards 10/26/2018 10/26/2018

SC Issuance Date for Consent Standards 11/05/2018 11/05/2018

Tech Session Association Meeting for Standards with CAMs

Appeals andIssuance

Appeal Closing Date for Standards with CAMs

SC Issuance Date for Standards with CAMs

TC = Technical Committee or PanelCC = Correlating Committee

As of 8/30/2016


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Attachment D: NFPA 85 Chapter 8

Public Input Report


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Public Input No. 100-NFPA 85-2016 [ Global Input ]

Replace "practicable" with "practical"

Statement of Problem and Substantiation for Public Input

Something is practicable if it can be done by any means, no matter how impractical. Practical is a word engineers use to allow judgment when making engineering decisions.

Submitter Information Verification

Submitter Full Name: Theodore Lemoff

Organization: TLemoff Engineering

Street Address:

City:

State:

Zip:

Submittal Date: Wed Oct 05 09:52:10 EDT 2016

Copyright Assignment

I, Theodore Lemoff, hereby irrevocably grant and assign to the National Fire Protection Association (NFPA) all and full rights incopyright in this Public Input (including both the Proposed Change and the Statement of Problem and Substantiation). Iunderstand and intend that I acquire no rights, including rights as a joint author, in any publication of the NFPA in which thisPublic Input in this or another similar or derivative form is used. I hereby warrant that I am the author of this Public Input and that Ihave full power and authority to enter into this copyright assignment.

By checking this box I affirm that I am Theodore Lemoff, and I agree to be legally bound by the above Copyright Assignmentand the terms and conditions contained therein. I understand and intend that, by checking this box, I am creating an electronicsignature that will, upon my submission of this form, have the same legal force and effect as a handwritten signature

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Public Input No. 215-NFPA 85-2017 [ Global Input ]

All technical committees should review the proposed changes to the definitions of "trip," "interlock,"and "permissive," as well as the recommendations below:

Draft Definitions and Guidelines developed by the

NFPA 85 Correlating Committee and Fundamentals Committee

Draft definitions for interlock, permissive, and trip.

· Interlock: A function which prevents, limits, stops, or initiates the operation of equipment or a subsequentfunction.

o Annex language: An interlock can consist of a sensing function, a control function, and anoutput or a final control element. The interlock can be accomplished with the use of anycombination of electrical devices, mechanical devices, or logic.

· Permissive: An interlock that functions only to allow initiation of the operation of equipment or asubsequent function

· Trip: An interlock that shuts down equipment when a predefined set of conditions exists.

It was decided that permissive and trip should be subdefinitions under interlock, but they should also appear inalphabetical order with a reference back to the interlock section, similar to what is done for “coal” in 3.3.30.

Recommendations for other Chapters. The following recommendations have been developed for the use of“interlock” and related terms throughout the code:

· “Safety device”, “protective device”, “interlock device” and “safety interlock device” appear to besynonymous. The Fundamentals Committee suggests using "interlocks" or "interlocks and associated devices"as appropriate.

· “Safety function” is similar to the new definition of an interlock. The Fundamentals Committee suggestsusing the term interlock.

· “Master fuel trip device” is not defined in Chapter 3, and is only used in Chapter 7 and its Annex. If this isintentionally different from a master fuel trip relay, it should be defined in Chapter 3. Otherwise, it should bereplaced with “master fuel trip relay”.

· “Safety shutdown” is only used in Chapters 3, 4, and 5, and the Annex to Chapters 5 and 7. Forconsistency throughout the document, the Fundamentals Committee recommends replacement with “trip” or“master fuel trip”, as appropriate. The Fundamentals Committee will be removing the term from Chapters 3 and4.

· “Emergency shutdown” is used in Chapters 4, 6, 7, 8, and 10, and the Annex to Chapters 4, 6, and 7, aswell as Annex B. This appears to be the same as a safety shutdown, so the Committee recommendsreplacement with “trip” or “master fuel trip” as in the comment above. The Fundamentals Committee will beremoving the term from Chapter 4.

· “Abnormal shutdown” is only used twice, both times in Chapter 6. This appears to be synonymous with“trip” and for consistency, that term should be substituted.

· “Interlock system” is used in Chapters 4, 5, 6, 7, 8, and 9. The Fundamentals Committee will be removingthe term from Chapter 4 by replacing it with “interlocks” and recommends replacement in other chapters.


To comply with the recommendations of the Fundamentals TC.


Submitter Full Name: Joseph Fehr

Organization: Sega, Inc.


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Street Address:

City:

State:

Zip:

Submittal Date: Wed Jan 04 15:10:04 EST 2017

Copyright Assignment

I, Joseph Fehr, hereby irrevocably grant and assign to the National Fire Protection Association (NFPA) all and full rights in copyright in this PublicInput (including both the Proposed Change and the Statement of Problem and Substantiation). I understand and intend that I acquire no rights,including rights as a joint author, in any publication of the NFPA in which this Public Input in this or another similar or derivative form is used. Ihereby warrant that I am the author of this Public Input and that I have full power and authority to enter into this copyright assignment.

By checking this box I affirm that I am Joseph Fehr, and I agree to be legally bound by the above Copyright Assignment and the terms andconditions contained therein. I understand and intend that, by checking this box, I am creating an electronic signature that will, upon mysubmission of this form, have the same legal force and effect as a handwritten signature


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Public Input No. 146-NFPA 85-2016 [ Section No. 8.4.2.1.2 ]

8.4.2.1.2 Gaseous Fuels.

8.4.2.1.2.1

Two safety shutoff valves in series, with proof of closure, shall be provided in the line to the combustionturbine. An A valve proving system or an automatic vent valve shall be provided between the two valves(double block and vent).

8.4.2.1.2.2

Three safety shutoff valves in series, with proof of closure, shall be provided in each fuel line to thecombustion turbine for units with combustion turbine purge credit provisions in accordance with 8.8.4.6.Automatic Valve proving sytems or automatic vent valves shall be provided between these valves (tripleblock and double vent). ,


The valve proving system and vent valves offer equivalent safety, and the use of these devices had already permitted in single burner boiler since the late 1990s.


Submitter Full Name: Kevin Carlisle

Organization: Karl Dungs, Inc.

Street Address:

City:

State:

Zip:

Submittal Date: Fri Dec 16 14:48:12 EST 2016

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8.4.2.2.1

The HRSG system's required interlocks required permissives shall prevent starting of the combustionturbine unless the HRSG starting conditions are satisfied, which shall include but not be limited to thefollowing:

(1) The water levels in drum(s), if provided, are within the defined start-up range.

(2) The feedwater supply system is available to respond to demand.

(3) The pressure in steam or water spaces is not high.

(4) The exit temperature of duct burner(s), if provided, is not high.

(5) The position of stack closure, if provided, is correct.

(6) The pressure in the HRSG enclosure is not high.

(7) Where a combustion turbine purge credit is being used, all fuel systems connected to the HRSG aresatisfactorily isolated.


This change clarifies the meaning of the paragraph in accordance with the definitions recommended by the Fundamentals Committee.


Submitter Full Name: Dwight Hyche

Organization: Swiss Re America Holding Corpo

Affilliation: HRS Committee Chair

Street Address:

City:

State:

Zip:

Submittal Date: Fri Sep 09 11:13:51 EDT 2016


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8.4.2.2.3 *

Signals shall be provided to the combustion turbine control system to initiate a change in the combustionturbine operating mode if HRSG conditions deviate beyond preset safety limits, including but not limited tothose listed in Table 8.4.2.2.3.

Table 8.4.2.2.3 HRSG Interlock Conditions and Responses

Condition Response

Water in drum(s) below minimum permittedlevel

Reduce combustion turbine load or trip combustion

turbine as required by HRSG manufacturer. *

Pressure in combustion turbine exhaustplenum high

Trip combustion turbine.

Position of stack closure (if provided) notcorrect (See 8.9.5.1.2 and 8.9.5.1.3.)

Reduce combustion turbine load

or initiate a fired shutdown of the combustion turbine

, initiate a combustion turbine normal shutdown or trip .

*Due to rapid steam pressure rise following a steam turbine trip, drum water level drops but inventoryremains the same. A combustion turbine response to this transient should not be required, and a delay forthe time required immediately after the steam turbine trip to permit pressure recovery and level restorationshould be permitted.


This change clarifies the meaning of the paragraph in accordance with the definitions of terms including "trip" and "interlock" recommended by the Fundamentals Committee.





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8.4.2.2.4

Where a HRSG is not provided, an interlock a permissive shall prohibit starting the combustion turbine ifthe combustion turbine exhaust system pressure is high.


This change clarifies the meaning of the paragraph in accordance with the definitions of terms including "trip", "permissive" and "interlock" recommended by the Fundamentals Committee





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Public Input No. 125-NFPA 85-2016 [ Section No. 8.5.3 ]

8.5.3 * HRSG Implosions.

For HRSGs that use an ID fan, the HRSG negative transient design pressure shall be at least as negativeas, but shall not be required to be more negative than, the test block maximum head capability of the IDfan when corrected to ambient temperature.


There are inconsistencies in NFPA 85 regarding structural design being based on the maximum head capabilities of the fans versus the fan test block conditions. The fan test block condition is not the same as the maximum head capability but the Code seems to use the terms interchangeably. A typical centrifugal fan curve peaks before dropping to the test block point, so the most damage it is capable of is better represented by the maximum head capability of the fan rather than the test block. Ambient air should be utilized as the basis for determining the maximum head capability because the coldest air condition anticipated for the site would provide the highest maximum head for the fan. For this reason, the term test block, where it is currently used in the Code, should be replaced with maximum head capability and ambient air should be the basis for that determination.


Submitter Full Name: Dale Evely

Organization: Southern Company Services Inc

Street Address:

City:

State:

Zip:

Submittal Date: Tue Nov 29 06:01:09 EST 2016


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Public Input No. 67-NFPA 85-2016 [ Section No. 8.7.3.2.1 [Excluding any Sub-Sections] ]

The following alarms shall be required:

(1) Each interlock trip Each trip , alarmed individually

(2) HRSG steam pressure (high) — high HRSG pressure at each steam pressure level

(3) Loss of interlock power

(4) Loss of control power

(5) Burner (if provided) safety shutoff valves not closed

(6) Steam drum(s) (if provided) water level (low)

(7) Loss of combustion turbine load

(8) Duct burner (if provided) outlet temperature (high)

(9) Flame detector (if provided) cooling air pressure (low)

(10) Loss of augmented air (if provided) supply

(11) Class 1 or Class 2 ignition fuel header (if provided) pressure (high and low)


This change clarifies the meaning of the paragraph in accordance with the definitions of terms including "trip", "permissive" and "interlock" recommended by the Fundamentals Committee.





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Public Input No. 103-NFPA 85-2016 [ Section No. 8.7.3.2.1.1 ]

8.7.3.2.1.1

Loss of interlock power shall be sensed and alarmed and shall include all sources of power required tocomplete interlock functions. For example, if both a 125 V dc electric circuit and a compressed air circuitare required for an interlock scheme, then loss of either shall be annunciated.


The deleted text is not a requirement and is not permitted in the numbered paragraphs of an NFPA Code by the Manual of Style. The text is informative, and could be relocated to Annex A.




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8.7.3.2.1.2

Loss of control power shall be sensed and alarmed to include any sources of power for the controlsystems. For example, if both a 125 V dc electric circuit and a compressed air circuit are required forcontrol, then loss of either shall be annunciated.


The deleted text is not a requirement and is not permitted in the numbered paragraphs of an NFPA Code by the Manual of Style. The text is informative, and could be relocated to Annex A




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Submittal Date: Mon Oct 17 10:57:32 EDT 2016


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8.7.4.1.4 Removal of Safety Interlock Device.

8.7.4.1.4.1

Whenever a safety interlock device has been removed from service for maintenance, testing, or repair, thedevice shall be tagged and the action governed by operating procedures.

8.7.4.1.4.2

Other means shall be substituted to supervise the interlock function.


The intent of these sections is covered already in Chapter 4, Paragraph 4.5.5 and is not needed in Chapter 8.





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8.7.4.1.5

The design of an interlock system interlocks and associated devices shall include the following:

(1) Supervision of the starting procedure and operation

(2) Tripping of the minimum amount of equipment in the required sequence when the safety of personnelor equipment is jeopardized

(3) Indication of the initiating cause of the trip and prevention of the start of any portion of the processuntil operating conditions are established

(4) Coordination of the trip devices the trips and associated devices into an integrated system

(5) Provisions of instrumentation to enable the operator or automatic equipment to complete theoperating sequence

(6) Provision for preventive maintenance

(7) Interlocks that do not require defeating in order to start or operate equipment

(8) The independence of mandatory duct burner master fuel trip sensing elements and circuits from allother control elements and circuits except as permitted in 8.7.4.1.5.1 and 8.7.4.1.5.2

(9) Prevention of the misoperation of the interlock system interlocks and associated devices due to aninterruption or restoration of the interlock energy supply

8.7.4.1.5.1

Individual burner flame detectors shall be permitted to be used for initiating duct burner master fuel tripsystems.

8.7.4.1.5.2

Combustion turbine exhaust gas flow, combustion turbine load, airflow measurement, and auctioneereddrum level signals from the HRSG control system shall be permitted to be used for a master fuel trip,provided all the following conditions are met:

(1) These interlocks are hardwired into the burner management system.

(2) Tripping set points are protected from unauthorized changes.

(3) Any single component failure of these sensing elements and circuits does not prevent a mandatorymaster fuel trip.







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8.7.4.1.5.1

Individual burner flame detectors shall be permitted to be used for initiating duct burner master fuel tripsystems trips .







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8.7.4.1.6

Interlock functions Interlocks including those functions outside the burner management system shall meetthe functional requirements of 4.11.4.







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Public Input No. 71-NFPA 85-2016 [ Section No. 8.7.4.3 ]

8.7.4.3 Duct Burner Master Fuel Trip.

For an operating duct burner, including the start-up or shutdown sequences, a duct burner master fuel tripshall be initiated by the following conditions:

(1) Low fuel pressure

(2) Combustion turbine exhaust or fresh air (if provided) flow across the duct burner that drops below theminimum required for operation of the duct burner as specified by the burner manufacturer or asproven by trial; it is permitted to infer this flow from the operating status of the combustion turbine,fresh air fan (if provided), and damper(s) (if provided) position(s)

(3) Combustion turbine trip except for systems operating as defined in 8.10.2.4

(4) Loss of all burner flame other than during a normal duct burner shutdown sequence

(5) Partial loss of flame determined to create a hazardous accumulation of unburned fuel at any burnerelement or zone

(6) Loss of duct burner element(s) resulting in incorrect element firing configuration, in accordance with8.8.5.8.3.2

(7) Light-off failure of first burner in multiple burner operation

(8) Failure to prove a safety shutoff valve closed on command to close

(9) Closing of last individual burner safety shutoff valve other than during a normal duct burner shutdownsequence

(10) High fuel pressure

(11) Low water level on high pressure section of HRSG

(12) Loss of energy supply for HRSG control, burner management, or interlock system trips andassociated devices.

(13) Low atomizing media (if provided) supply pressure

(14) Detection of burner management system malfunction

(15) Manual trip [See 4.11.7(8) .]

(16) Loss of augmented air supply where the operation of the duct burner requires augmented air

(17) Fresh air (if provided) transfer failure (See 8.10.2.4.)

(18) Logic controller failure [See 4.11.7(10) and 4.11.7(11).]







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Public Input No. 60-NFPA 85-2016 [ Section No. 8.8.4.1 [Excluding any Sub-Sections] ]

The purge of the combustion turbine shall be in accordance with the manufacturer's instructions and withthe shall be completed initially in accordance with 8.8.4.2. After initial combustion turbine purge iscompleted shall be in accordance with the requirements of 8.8.4.2 (Initial and 5X changes) , 8.8.4.6(Purge credit with 8-day period) or 8.8.4.7 (Purge credit indefinite) as applicable.


Section 8.8.4.1 seems confusing to HRSG users with gas turbines in regards to GT Purging requirements. It's not 100% clear that initial 5X air changes, minimum 5 minutes is required prior to moving on with achieving GT Purge Credit routine. Have revceived numerous calls from customers, OEMs and internal asking how to interpret the related sections of code.


Submitter Full Name: Randy Kleen

Organization: General Electric Company

Affilliation: NFPA 85 Committee Member, FUN and HRS

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8.8.4.2.1 Purge of the HRSG or other exhaust treatment systems prior to the light-off of the combustionturbine shall be accomplished by at least five volume changes at purge rate and for a duration of not lessthan 5 minutes.

8.8.4.2.2 Purge of bypass systems shall be accomplished as follows:

(1) Where the bypass system includes an exhaust treatment system (such as a Selective CatalyticReduction system) the purge shall be accomplished by at least five volume changes at purge rate and for aduration of not less than 5 minutes.

(2) Where the bypass system consists of only a stack (with or without a silencer), the purge shall be inaccordance with NFPA 37.


I have heard some people share the opinion that for the combination of an HRSG and a diverter-damper with a bypass stack the NFPA 85 purge requirements apply to both flow paths; that is, the five volume change with a minimum duration of 5 minutes applies equally to the HRSG flow path and the bypass stack flow path. This is presumed based on Clauses 8.9.2.1.1 and 8.9.2.2.1, where it is stated that “A purge of both the HRSG enclosure and the bypass system shall be completed as required in 8.8.4 … ”.

A calculation of 5 minutes of flow through the bypass stack at 8% of the turbine’s base load flow rate suggests this will result in more than 40 volume exchanges for a typical stack design. The 5-minute interpretation results in an unnecessary constraint on the owners / operators. The proposed change clarifies that the bypass system is not restricted by NFPA 85 purge requirements if there is no exhaust treatment equipment associated with the bypass flow path and points the user to the basic exhaust purge requirements of NFPA 37.


Submitter Full Name: Larry Danner

Organization: GE Power

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Submittal Date: Wed Sep 14 11:24:17 EDT 2016


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Following a combustion turbine normal shutdown, combustion turbine purge credit shall be permitted to beestablished for the next start-up event provided that the following requirements are met for each combustionturbine and duct burner fuel system.







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8.8.9 Duct Burner Emergency Shutdown Master Fuel Trip .

8.8.9.1

A duct burner master fuel trip shall be initiated by the conditions identified in 8.7.4.3.

8.8.9.2 Gaseous Fuel.

8.8.9.2.1

A duct burner master fuel trip shall stop all fuel flow to the HRSG from all burners by tripping the main andindividual burner safety shutoff valves.

8.8.9.2.2

The automated vent valve associated with the main safety shutoff valves shall be opened.

8.8.9.2.3

The igniter safety shutoff valves and individual igniter safety shutoff valves shall be tripped and ignitersparks de-energized.

8.8.9.2.4

Duct burner master fuel trips shall operate to stop all fuel flow to the burners.

8.8.9.3 Liquid Fuel.

8.8.9.3.1

A duct burner master fuel trip shall stop all fuel flow to the HRSG from all burners by tripping the main andindividual burner safety shutoff valves.

8.8.9.3.2

The igniter safety shutoff valves and individual igniter safety shutoff valves shall be tripped and ignitersparks de-energized.

8.8.9.3.3

Duct burner master fuel trips shall operate to stop all fuel flow to the burners.

8.8.9.4

The burners shall not be reignited until the initiating trip condition has been investigated and corrected anda duct burner purge has been completed.


This change clarifies the meaning of the paragraph in accordance with the definitions of terms including "trip", "permissive" and "interlock" recommended by the Fundamentals Committee.





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Public Input No. 111-NFPA 85-2016 [ Section No. 8.9.1.6 ]

8.9.1.6

The owner or owner's representatives shall address the implications of the following hazards associatedwith damper applications:

(1) Due to the physical size, shape, and mass, a damper cannot be assumed to fully seal a combustionturbine exhaust gas flow path.

(2) A leaking fuel valve or a combustion turbine false start will result in an explosive mixture in theHRSG on either or both sides of a damper during shutdown periods.

(3) Failure to purge an explosive mixture prior to introduction of hot turbine exhaust gas will result inignition of the mixture. Even at full speed and no load, the combustion turbine exhaust temperaturescan be above the autoignition temperatures for combustion turbine and HRSG fuels.

(4) Systems using two stacks (HRSG and bypass), with or without dampers, tend to induce a reverseflow of fresh air through the HRSG as a result of the high temperature combustion turbine exhaustgas flow up the bypass stack.

(5) Failure of damper-operating mechanisms will allow instantaneous reversal of damper position (fromopen position to closed position and vice versa) due to aerodynamic effects with the following results:

(6) Sudden closure of an operating combustion turbine free exhaust path will result in hightransient duct internal pressures.

(7) These high pressures can cause distortion of the HRSG enclosure and rupture of the ductexpansion joints.

(8) Combustion turbine exhaust temperatures are high enough to ignite and sustain the basic iron fireoxidation reaction.


Paragraph 8.9.1.5 is not an enforceable requirement and should be either deleted or revised to be an enforceable requirement. The paragraph requires that several items be "addressed", but no guidance is provided on what methods are acceptable. While the term "addressed" as used in this context is understood by most professionals in the field, there is nothing to prevent a contractor to state that the items have been addressed and ignored.




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8.9.2 Purge.

8.9.2.1 Unfired HRSG.

8.9.2.1.1

A purge of both the HRSG enclosure and the bypass system shall be completed as required in 8.8.4 priorto the admission of combustion turbine exhaust gas into the HRSG.

8.9.2.1.2

Following the purge as required in 8.9.2.1.1, it shall be permitted to interrupt the flow through the HRSGusing the bypass stack.

8.9.2.1.3

Combustion turbine exhaust flow shall be permitted to re-enter the HRSG at a later time without repurging,provided the combustion turbine has been in continuous operation with no trips or misfires.

8.9.2.1.4

Where HRSG isolation is maintainedand the combustion turbine operation has been interrupted, thecombustion turbine shall be permitted to purge and operate with combustion turbine exhaust through thebypass stack.

8.9.2.1.4.1

When it is desired to return the HRSG to service, a purge of the HRSG enclosure shall be performed asrequired by 8.9.2.1.1.

8.9.2.1.4.2

After the purge of 8.9.2.1.4.1, an interruption as allowed by 8.9.2.1.2 shall be permitted.

8.9.2.1.4.3

Where the combustion turbine operation has been interrupted and it is desired to return the HRSG toservice, the combustion turbine shall be permitted to continue operating and the combustion turbineexhaust shall be permitted to be used to purge the HRSG, provided the exhaust temperature is at least56°C (100°F) lower than the autoignition temperature of the fuels designed for use in the specificcombustion turbine.

8.9.2.2 Fired HRSG.

8.9.2.2.1

A purge of both the HRSG enclosure and the bypass system shall be completed as required in 8.8.4 priorto the admission of combustion turbine exhaust gas into the HRSG.

8.9.2.2.2

Where HRSG isolation is continuously maintained and the combustion turbine operation is interrupted, thecombustion turbine shall be permitted to purge and operate with combustion turbine exhaust through thebypass stack.

8.9.2.2.2.1

When HRSG isolation is removed, a purge of the HRSG enclosure shall be performed as required by8.9.2.2.1, except as permitted in 8.9.2.2.4.

8.9.2.2.2.2

Where the combustion turbine operation has been interrupted and it is desired to return the HRSG toservice, the combustion turbine shall be permitted to continue operating and the combustion turbineexhaust shall be permitted to be used to purge the HRSG, provided the exhaust temperature is at least56°C (100°F) lower than the autoignition temperature of the fuels designed for use in the specificcombustion turbine and the duct burner.


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8.9.2.2.2.3

Where the combustion turbine has been in continuous operation with no trips or misfires and it is desiredto return the HRSG to service, the combustion turbine shall be permitted to continue to be operated andthe combustion turbine exhaust may be used to purge the HRSG, provided the exhaust temperature is atleast 56°C (100°F) lower than the autoignition temperature of the fuels designed for use in the duct burner.

8.9.2.2.3

If damper(s) operation or other cause(s) results in the exhaust mass flow through the HRSG falling belowthe purge rate required in 8.8.5, a repurge as required in 8.8.5 shall be performed prior to lighting the ductburner.

8.9.2.2.4*

When it is desired that the HRSG be bypassed for a period of time and then for the HRSG to be returnedto service by means of damper positioning without a power interruption, one of the following conditionsshall be met:

(1) A continuous flow of at least the purge rate of exhaust or fresh air shall be maintained through theHRSG when the combustion turbine is operating.

(2) The combustion turbine is in operation without trips or misfires and the duct burner fuel systemsatisfies the isolation requirements for a combustion turbine purge credit in accordance with 8.8.4.6.

8.9.2.3* Returning HRSG to Service.

Where combustion turbine exhaust flow is to be reintroduced to the HRSG through operation of the stackdiverter damper, the combustion turbine load and damper sequence of operation shall be in accordancewith the HRSG manufacturer’s operating instructions.

Additional Proposed Changes

File Name Description Approved

NFPA_85_TIA_Log_No_1136.pdf NFPA 85 TIA 15-1 Log No. 1136


“NOTE: This public input originates from Tentative Interim Amendment No. 15-1 (Log 1136) issued by the Standards Council on November 11, 2014 and per the NFPA Regs., needs to be reconsidered by the Technical Committee for the next edition of the Document.

Submitter’s Substantiation: This TIA addresses ambiguities in the section discussed in the January 16, 2014 meeting of the Technical Committee on Heat Recovery Steam Generators and also corrects an inconsistency between an unfired HRSG and a fired HRSG when returning the HRSG into service after bypass operation. There is an inconsistency between an unfired HRSG and a fired HRSG when returning the HRSG into service after bypass operation. 8.9.2.1.3 allows combustion turbine exhaust gas to re-enter the unfired HRSG without repurging provided the combustion turbine has been in continuous operation with no trips or misfires. When returning a fired HRSG to service and the combustion turbine exhaust gas is used as the purging medium, 8.9.2.2.2.2 currently requires the exhaust temperature to be at least 100°F less than the AIT of the fuels used in the design of the combustion turbine and the duct burner. As currently written, the requirements to return a natural gas supplementary fired HRSG with a combustion turbine bypass system operating behind a combustion turbine designed to operate on both natural gas and distillate oil to service after operating in by-pass mode will result in an in


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terruption of power and undue wear on the CT because the combustion turbine exhaust temperature would need be reduced to where the CT flame would need to be extinguished. Following the logic of 8.9.2.1.3, if the combustion turbine has been in continuous operation with no trips or misfires, the combustion turbine exhaust flow should need only be 100°F less than the AIT of the fuels used in the design of the duct burner and NOT the combustion turbine. The proposed changes correct this inconsistency and clarify what the temperature of the purging medium must be considering previous combustion turbine operation. Emergency Nature: As currently written, the requirements will result in unnecessary interruption of power or undue costs to implement the provisions of 8.9.2.2.4 where they would not otherwise be required. The proposed changes were discussed in meetings of the Technical Committee on Heat Recovery Steam Generators however the current revision cycle will not allow for the changes to be included in the 2015 Edition.


Submitter Full Name: TC ON BCS-HRS

Organization: NFPA TC ON HEAT RECOVERY STEAM GENERATORS

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Submittal Date: Wed Oct 26 15:29:19 EDT 2016


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(Note: For further information on NFPA Codes and Standards, please see www.nfpa.org/codelist) Copyright © 2014 All Rights Reserved

NATIONAL FIRE PROTECTION ASSOCIATION

Tentative Interim Amendment

NFPA® 85 Boiler and Combustion Systems Hazards Code

2015 Edition

Reference: 8.9.2 TIA 15-1 (SC 14-8-20 / TIA Log #1136) Note: Text of the TIA issued and incorporated into the text of the document, therefore no separate publication is necessary. 1. Revise 8.9.2 to read as follows: 8.9.2 Purge. 8.9.2.1 Unfired HRSG. 8.9.2.1.1 A purge of both the HRSG enclosure and the bypass system shall be completed as required in 8.8.4 prior to the admission of combustion turbine exhaust gas into the HRSG. 8.9.2.1.2 Following the purge as required in 8.9.2.1.1, it shall be permitted to interrupt the flow through the HRSG using the bypass stack. 8.9.2.1.3 Combustion turbine exhaust flow shall be permitted to re-enter the HRSG at a later time without repurging, provided the combustion turbine has been in continuous operation with no trips or misfires. 8.9.2.1.4 Where HRSG isolation is maintained and the combustion turbine operation has been interrupted, the combustion turbine shall be permitted to purge and operate with combustion turbine exhaust through the bypass stack. 8.9.2.1.4.1 When it is desired to return the HRSG to service, a purge of the HRSG enclosure shall be performed as required by 8.9.2.1.1 8.9.2.1.4.2 After the purge of 8.9.2.1.4.1, an interruption as allowed by 8.9.2.1.2 shall be permitted. 8.9.2.1.4.3 Where the combustion turbine operation has been interrupted and it is desired to return the HRSG to service, the combustion turbine shall be permitted to continue operating and the combustion turbine exhaust shall be permitted to be used to purge the HRSG, provided the exhaust temperature is at least 56 C (100 F) lower than the autoignition temperature of the fuels designed for use in the specific combustion turbine. 8.9.2.2 Fired HRSG. 8.9.2.2.1 A purge of both the HRSG enclosure and the bypass system shall be completed as required in 8.8.4 prior to the admission of combustion turbine exhaust gas into the HRSG. 8.9.2.2.2 Where HRSG isolation is continuously maintained and the combustion turbine operation is interrupted, the combustion turbine shall be permitted to purge and operate with combustion turbine exhaust through the bypass stack. 8.9.2.2.2.1 When HRSG isolation is removed, a purge of the HRSG enclosure shall be performed as required by 8.9.2.2.1, except as permitted in 8.9.2.2.4.


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(Note: For further information on NFPA Codes and Standards, please see www.nfpa.org/codelist) Copyright © 2014 All Rights Reserved

NATIONAL FIRE PROTECTION ASSOCIATION

8.9.2.2.2.2 Where the combustion turbine operation has been interrupted and it is desired to return the HRSG to service, the combustion turbine shall be permitted to continue operating and the combustion turbine exhaust shall be permitted to be used to purge the HRSG, provided the exhaust temperature is at least 56 C (100 F) lower than the autoignition temperature of the fuels designed for use in the specific combustion turbine and the duct burner. 8.9.2.2.2.3 Where the combustion turbine has been in continuous operation with no trips or misfires and it is desired to return the HRSG to service, the combustion turbine shall be permitted to continue to be operated and the combustion turbine exhaust may be used to purge the HRSG, provided the exhaust temperature is at least 56 C (100 F) lower than the autoignition temperature of the fuels designed for use in the duct burner. 8.9.2.2.3 If damper(s) operation or other cause(s) results in the exhaust mass flow through the HRSG falling below the purge rate required in 8.8.5, a repurge as required in 8.8.5 shall be performed prior to lighting the duct burner. 8.9.2.2.4* When it is desired that the HRSG be bypassed for a period of time and then for the HRSG to be returned to service by means of damper positioning without a power interruption, one of the following conditions shall be met:

(1) A continuous flow of at least the purge rate of exhaust or fresh air shall be maintained through the HRSG when the combustion turbine is operating.

(2) The combustion turbine is in operation without trips or misfires and the duct burner fuel system satisfies the isolation requirements for a combustion turbine purge credit in accordance with 8.8.4.6.

8.9.2.3* Returning HRSG to Service Where combustion turbine exhaust flow is to be reintroduced to the HRSG through operation of the stack diverter damper, the combustion turbine load and damper sequence of operation shall be in accordance with the HRSG manufacturer’s operating instructions. Issue Date: November 11, 2014 Effective Date: December 1, 2014


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8.9.5.2.1

If the HRSG system is designed for duct burner operation with intermediate damper position(s), minimumexhaust flow or incorrect damper position shall be interlocked to initiate shall initiate a duct burner masterfuel trip.







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8.11.2

The purge requirements of 8.8.4 shall be met when 8 .8 is applicable.

Rational: the 8.8 applies "where gaseous or liquid fuels are being burned in HRSG or other combustionturbine exhaust system". I don't think the purpose of 8.11.2. is to make the 8.8.4. applicable for combustionturbine exhaust system where gaseous or liquid fuels are not being burned.


The 8.8 applies "where gaseous or liquid fuels are being burned in HRSG or other combustion turbine exhaust system". I don't think the purpose of 8.11.2. is to make the 8.8.4. applicable for combustion turbine exhaust system where gaseous or liquid fuels are not being burned.


Submitter Full Name: Brice Chabrier

Organization: Siemens Canada Limited

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Submittal Date: Tue Mar 15 13:38:09 EDT 2016


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Public Input No. 75-NFPA 85-2016 [ Section No. A.8.7.1 ]


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A.8.7.1

The user is encouraged to use judgment in the application of the following guidelines for all processfunctions and safety functions contained interlocks contained in the distributed control system.

For data transmission, the following should be considered:

(1) Every input should be sampled at intervals no longer than 1 second. Every output should be updatedat intervals no longer than 1 second.

(2) For protective actions, the system should be able to convert a changed input sensor value to acompleted output control action in less than 250 milliseconds.

(3) Changes in displayed data or status should be displayed within 5 seconds.

(4) Data acquisition and transmission systems should be protected from noise pickup and electricalinterference.

(5) In redundant systems, the data links should be protected from common mode failures. Wherepractical, redundant data links should be routed on separate paths to protect against physical damagethat disables both data links.

For hardware, the following should be considered:

(1) The hardware selected should have adequate processor capacity to perform all the functions requiredfor start-up sequencing, normal operation alarming, monitoring, and shutdown of the controlledequipment. Capacity also should be available for data storage and sorting; this capacity can bepermitted to be located in a separate processor.

(2) Selection should take into consideration the requirements for reliability, maintainability, and electricalclassification.

(3) The hardware should provide for automatic tracking between automatic and manual functions to allowfor immediate seamless transfer.

(4) The hardware should be capable of stable dynamic control.

(5) The hardware should be capable of thorough self-diagnosis.

(6) Consideration should be given to all levels and types of electrical interference that can be tolerated bythe hardware without compromising its reliability or effectiveness.

(7) Fail-safe operation should be obtained through a thorough and complete analysis of each control loopand by providing for a failure of that loop (i.e., valve/actuator) to cause a fail-safe position.

For software, the following should be considered:

(1) The software package should be designed to include all logic to provide a safe and reliable controlsystem. When the software calls for the operation of a field safety device field device associated withan interlock , a feedback signal should be provided to prove that the requested operation has takenplace, and an alarm should be actuated if the action is not confirmed in a specified time.

(2) The software package should be checked to ensure that no unintended codes or commands arepresent (e.g., viruses or test breaks). The software package should be tested and exercised beforebeing loaded into the plant site computers or processors.

(3) The software system should be protected from inadvertent actions from operators and also should betamperproof.

(4) Written procedures should specify the functions that can and cannot be accessed by the operator andthose functions that require additional authorization for access.

(5) The software should be permitted to provide for authorized on-line changes of the timers and setpoints, provided the safety of the operating equipment is not compromised.

(6) The software should implement and enhance the self-diagnostic hardware that has been provided.




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Attachment E: Review of Fundamentals Technical Committee Actions


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First Revision No. 102-NFPA 85-2017 [ Section No. 1.1.2 ]

1.1.2

This code covers strength of the structure, operation and maintenance procedures, combustion and draftcontrol equipment, safety interlocks, alarms, trips, and other related controls that are essential to safeequipment operation.


Submitter Full Name: Laura Montville

Organization: [ Not Specified ]

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Submittal Date: Tue Jan 17 09:44:28 EST 2017

Committee Statement

Committee Statement: To align with the interlock definitions included in Chapter 3. (FRs 103, 104, 105)

Response Message:

Public Input No. 22-NFPA 85-2016 [Section No. 1.1.2]

National Fire Protection Association Report http://localhost:8084/TerraViewWeb/ContentFetcher?commentParams=...

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Committee Input No. 135-NFPA 85-2017 [ Section No. 1.1.4 ]

1.1.4

Chapter 5, Single Burner Boilers, covers single burner boilers that fire the following fuels:

(1) Fuel Natural gas as defined in 3.3. 64 71 .10.

(2)

(3) Fuel oil as defined in 3.3.63.3

Fuel gas and fuel

(4) of Grades 2, 4, 5, or 6

(5) Gas and oil that are fired simultaneously for fuel transfer

(6) Fuel gas Gas and fuel oil that are fired simultaneously and continuously

(7) Non-commercial grade fuel gases




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Committee Statement

CommitteeStatement:

The scope of Chapter 5 written in Chapter 1 needs to match the contents of the equipment specificchapter. The Fundamentals Committee will reconsider a revision to the Chapter 5 scope at theSecond Draft meeting, once additional language has been added to Chapter 5 by the SBBCommittee to cover the other fuels.

----

The SBB Committee wishes to amend the scope statement to define and address the use ofnon-commercial fuels in its chapter. Non-commercial fuels such as landfill gas, process off-gases,etc. are used in increasing single burner applications. The Technical Committee will continue to addmaterial to address specific concerns and requirements when using these types of fuels.

ResponseMessage:


* Other commercial grade fuel gas having a calorific value and characteristics similar to natural gas


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First Revision No. 108-NFPA 85-2017 [ Section No. 1.1.9.1 ]

1.1.9.1

Where solid fuel is fired simultaneously with other fuels (e.g., a solid fuel stoker fired in combination withfuel gas, fuel oil, or pulverized auxiliary fuel), additional controls and interlocks shall include those coveredin Chapters 5, 6, and 9.

Exception No. 1: The purge requirements of Chapters 5 and 6 shall not be required when the stoker isfiring and the boiler is on-line. In those cases, if no cooling air is being provided to the auxiliary burners, apurge of their associated air supply ducts shall be provided.

Exception No. 2: Where fuel oil or fuel gas is fired in a supervised manual system in accordance withChapter 5 , the excessive steam pressure interlock shall not be required.




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Committee Statement

CommitteeStatement:

The FUN Technical Committee decided that the STO and SBB Technical Committees shouldaddress these exceptions in their respective chapters.

ResponseMessage:

Public Input No. 23-NFPA 85-2016 [Section No. 1.1.9.1]


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Committee Input No. 101-NFPA 85-2017 [ Chapter 2 ]

Chapter 2 Referenced Publications

2.1 General.

The documents or portions thereof listed in this chapter are referenced within this code and shall beconsidered part of the requirements of this document.

2.2 NFPA Publications.

National Fire Protection Association, 1 Batterymarch Park, Quincy, MA 02169-7471.

NFPA 30, Flammable and Combustible Liquids Code, 2015 edition.

NFPA 31, Standard for the Installation of Oil-Burning Equipment, 2011 edition.

NFPA 54, National Fuel Gas Code, 2015 edition.

NFPA 56 Standard for Fire and Explosion Prevention During Cleaning and Purging of Flammable GasPiping Systems,2014 edition.

NFPA 68 Standard on Explosion Protection by Deflagration Venting,2013 edition.

NFPA 69, Standard on Explosion Prevention Systems, 2014 edition.

NFPA 70® , National Electrical Code®, 2014 edition.

2.3 Other Publications.

2.3.1 ASCE Publications.

American Society of Civil Engineers, 1801 Alexander Bell Drive, Reston, VA 20191-4400.

ASCE 7, Minimum Design Loads for Buildings and Other Structures, 2010.

2.3.2 ASME Publications.

American Society of Mechanical Engineers, Two Park Avenue, New York, NY 10016-5990.

ASME B31.1, Power Piping, 2012 2016 .

ASME B31.3, Process Piping, 2012 2016 .

2.3.3 ASTM Publications.

ASTM International, 100 Barr Harbor Drive, P.O. Box C700, West Conshohocken, PA 19428-2959.

ASTM D388, Standard Classification of Coals by Rank, 2012 2015 .

ASTM D396, Standard Specification for Fuel Oils, 2012 2016 .

ASTM D409/D409M , Standard Test Method for Grindability of Coal by the Hardgrove-Machine Method,2012 2016 .

ASTM D1655, Standard Specification for Aviation Turbine Fuels, 2012 2016c .

ASTM D2880, Standard Specification for Gas Turbine Fuel Oils, 2003, reaffirmed 2010 2015 .

2.3.4 CGA Publications.

Compressed Gas Association, 14501 George Carter Way, Suite 103, Chantilly, VA 20151-2923 1788 .

ANSI/ CGA G-2.1/ANSI K61.1 , Safety Requirements for the Storage and Handling of AnhydrousAmmonia, 1999 2014

2.3.5 FCI Publications.

Fluid Controls Institute, 1300 Sumner Avenue, Cleveland, OH 44115.

ANSI/FCI 70-2, Control Valve Seat Leakage, 2006 2013 .


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2.3.6 Government Publications.

U.S. Government Printing Publishing Office, 732 North Capitol Street NW, Washington, DC20402 20401-0001 .

Title 29, Code of Federal Regulations, Part 1926.32, “General Safety and Health Provisions.”

2.3.7 IEC Publications.

International Electrotechnical Commission, 3, rue de Varembé, P.O. Box 131, CH-1211, Geneva 20,Switzerland.

IEC 61508, Functional Safety of Electrical/Electronic Programmable Electronic Safety-Related Systems,2010.

2.3.8 Military Specifications.

Department of Defense Single Stock Point, Document Automation and Production Service, Building 4/D,700 Robbins Avenue, Philadelphia, PA 19111-5094.

MIL-T-5624, Turbine Fuel, Aviation, Grade JP4, JP5, and JP5/JP8 ST, 1995.

2.3.9 Other Publications.

Merriam-Webster’s Collegiate Dictionary, 11th edition, Merriam-Webster, Inc., Springfield, MA, 2003.

2.4 References for Extracts in Mandatory Sections.

NFPA 13D, Standard for the Installation of Sprinkler Systems in One- and Two-Family Dwellings andManufactured Homes,2013 2016 edition.

NFPA 40, Standard for the Storage and Handling of Cellulose Nitrate Film,2011 2016 edition.

NFPA 72® , National Fire Alarm and Signaling Code,2013 2016 edition.

NFPA 850, Recommended Practice for Fire Protection for Electric Generating Plants and High VoltageDirect Current Converter Stations, 2015 edition.




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Submittal Date: Fri Jan 13 16:42:40 EST 2017

Committee Statement

CommitteeStatement:

The committee will review the referenced documents at the second draft meeting so that theywill have a more timely picture of what has been updated since the last edition was issued.



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3.3.25.3 Manual Supervised Burner Management System.

A burner management system by which a furnace is purged and a burner is started, ignited, and stoppedmanually . Interlocks are included to ensure that the operation follows established, proper procedures. withsupervision by interlocks.




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Committee Statement

Committee Statement: To align with the definition of interlock revised by FR 103.

Response Message:



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First Revision No. 139-NFPA 85-2017 [ Section No. 3.3.63.2.1 ]

3.3.63.2.1 Pulverized Coal.

Coal that is reduced to fine particles.

A.3.63.2.1 Pulverized Coal is typically reduced to a size such that at least 50 percent can pass through a200-mesh (74 microns) sieve.




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Committee Statement

Committee Statement: The definition is revised to remove requirements per the Manual of Style.

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3.3.63.6 3.1* Liquefied Petroleum Gas ( LP-Gas) .

A material that

Any material having a vapor pressure not exceeding that allowed for commercial propane that iscomposed predominantly of

any of

the following hydrocarbons , either by themselves (except propylene) or as mixtures

thereof

: propane, propylene,

n-butane, isobutane

butane (normal butane or isobutane) , and butylenes. [58 2017]

A.3.3.63.3.1 Liquefied Petroleum Gas (LP-Gas). In the pure state

propylene (Chemical Abstract Service 105-07- 01) has a vapor

pressure of 132.8 psig (915.72 kPa) at 70°F (21.1°C). The vapor

pressure of commercial propane (Chemical Abstract Service

74-98-6) at 70°F (21.1°C) is 124 psig (855 kPa). Although

commercial propane can contain some propylene, as in impurity,

propylene in the pure state does not meet the definition of

LP-Gas. Propylene in the pure state is commonly found in use

as an industrial fuel gas. (See NFPA 51.) [58 2017]




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Committee Statement

CommitteeStatement:

The definition is updated to be consistent with the applicable NFPA code, and the definition isrelocated to be a subdefinition of Fuel Gas.

ResponseMessage:


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3.3.63.9 3.2* Natural Gas.

A gaseous fuel occurring in nature and consisting mostly of a mixture of organic compounds, normallymethane, material that is composed primarily of methane and that can contain minor quantities of ethane,propane, nitrogen, and butane. other components.

A.3.3.63.3.2

The calorific value of natural gases varies between about 700 Btu/ft 3 and 1500 Btu/ft 3 ( 26.1 MJ/m3 and

55.9 MJ/m3 (700 Btu/ft 3 and 1500 Btu/ft 3 ), the majority averaging 1000 Btu/ft 3 ( 37.3 MJ/m3

(1000 Btu/ft 3 ).




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Committee Statement

CommitteeStatement:

The definition is updated to be consistent with NFPA 59A Liquefied Natural Gas, with someappropriate modification, and moved to be a subdefinition of Fuel Gas.

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3.3.63.10 * Pulverized Fuel.

Solid fuel that is reduced to fine particles.

A.3.3.63.10 Pulverized fuel is typically reduced to a size such that at least 50 percent will pass through a200-mesh (74 microns) sieve.




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Committee Statement: The definition is revised to remove requirements per the Manual of Style.

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3.3.64 63.3 Fuel Gas (Gas Fuel).

Gaseous fuels defined as Natural Gas (see 3.3.63.9) or LP-Gas (see 3.3.63.6).




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Committee Statement: Fuel gas belongs as a subdefinition of Fuel.

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3.3.66 Fuel Trip.

The automatic The total shutoff of a specific fuel as the result of an interlock or operator action .




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Committee Statement

CommitteeStatement:

This revision is based on the revised and new definitions for trip and interlock. Note that theoperator action is considered an interlock.

ResponseMessage:



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3.3.70 Hardwired.

The method of interconnecting signals or interlocks or devices to a logic system or between logic systemsusing a dedicated interconnection for each individual signal. When the term hardwired is applied to the logicsystem itself, it refers to the method of using individual devices and interconnecting wiring to program andperform the logic functions without the use of software-based logic solvers.




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Committee Statement

CommitteeStatement:

This revision is based on the revised definition of interlocks. Interlocks will now be defined as"functions" rather than "devices."

ResponseMessage:



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First Revision No. 141-NFPA 85-2017 [ Sections 3.3.73.1, 3.3.73.2, 3.3.73.3 ]

Sections 3.3.73.1, 3.3.73.2, 3.3.73.3

3.3.73.1 * Class 1 Igniter.

An igniter that is applied to ignite the fuel input through the burner and to support ignition under any burnerlight-off or operating conditions. Its location and capacity are such that it will provide sufficient ignitionenergy , generally in excess of 10 percent of full load burner input, at its associated burner to raise anycredible combination of burner inputs of both fuel and air above the minimum ignition temperature.


An igniter that is applied to ignite the fuel input through the burner under prescribed light-off conditions. It isalso used to support ignition under low load or certain adverse operating conditions. The range of capacityof such igniters is generally 4 percent to 10 percent of full load burner fuel input.


A small igniter applied particularly to fuel gas and fuel oil burners to ignite the fuel input to the burner underprescribed light-off conditions. The capacity of such igniters generally does not exceed 4 percent of the fullload burner fuel

A.3.3.73.1 The heat input of a Class 1 Igniter is generally in excess of 10 percent of maximum burner heatinput.

A.3.3.73.2 The heat input of a Class 2 Igniter is generally 4 percent to 10 percent of maximum burner heatinput.

A.3.3.73.3 The heat input of a Class 3 Igniter generally does not exceed 4 percent of maximum burnerheat input.

Supplemental Information

File Name Description

FR_141_A.3.3.63.1-3.docx




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Committee Statement

CommitteeStatement:

This revision removes the supplemental information from the igniter class definition, leaving theintended functional requirements intact, and relocates the supplemental information to theAnnex.

ResponseMessage:

Public Input No. 211-NFPA 85-2017 [New Section after A.3.3.33]


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Public Input No. 201-NFPA 85-2017 [Sections 3.3.73.1, 3.3.73.2, 3.3.73.3]


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Committee Input No. 143-NFPA 85-2017 [ New Section after 3.3.73.2 ]

3.3.73.3* Class 2 Special Igniter: An integrated burner-igniter system that utilizes a staged ignition systemwithin the burner. The primary igniter shall utilize oil or natural gas, or a plasma arc to ignite a portion of themain fuel stream which then provides ignition to the remainder of hte fuel stream. It is also used to supportignition under low load conditions where the main flame is proven.




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Committee Statement

CommitteeStatement:

The addition of these definitions relating to plasma arc igniters is contingent on action by the MBBCommittee.

---

Problem statement: Existing igniter systems are typically independent of the burner they areintended to ignite. A new technology is available whereby a portion of the main fuel stream is ignitedinternally in the burner barrel using oil, gas or plasma. The technology necessitates adjustments inoperating methodology for proper function. A task group comprised of members from BCS-MBB hasstudied this technology. This paragraph, in conjunction with other proposed paragraphs, addressesthat new technology.

SUBSTANTIATION: The proposed code revisions will provide minimum safety requirements that canenable US coal fired power plants to respond to real time market conditions in a timely manner. Thetechnology is desirable as it reduces or eliminates the amount of premium fuel used to start a boiler.

The technology has been successfully applied outside the US with installations in over 1,000 coalfired boilers in both the plasma and oil igniter form, and is available from multiplesuppliers/manufacturers. These installations have helped determine the suitability of the technologyand gives confidence in its safety potential. To enhance user safety a new igniter classification (a"Special" derivative of the existing Class II) which requires usage under prescribed conditions only.

The key distinguishing characteristic between the igniter classes in NFPA 85 is the difference inigniter ability to tolerate process variations. Based on the igniter ability to function under difficultconditions, the implementation and the privileges of the igniter class vary, Class I can be used under'all credible' conditions (3.3.73.1) but Class II can be used under 'prescribed' conditions only(3.3.73.2)

The restrictions to prescribed conditions is also required due to the difficullty in igniter flame provingin some of these applications for the plasma arc style. The location of the igniter fllame inside theburner barrel, where it cannot be reliably sensed, requires the use of a proven main flame under'non-initial' start-up conditions for safe operation.

This revision will help avoid unsafe application of this new technology by providing clear and


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consistent minimum safety requirements.

ResponseMessage:

Public Input No. 157-NFPA 85-2016 [New Section after 3.3.73.2]



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* Integrated Burner-Igniter System

An igniter integral to a staged ignition burner assembly, whereby a portion of the main fuel streamis raised to a temperature above its auto-ignition temperatureand this heated fuel then ignites theremainder of the main fuel stream as it enters the furnace.




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Committee Statement

CommitteeStatement:


---

Problem Statement

Existing igniter systems are typically independent of the burner they are intended to ignite. A newtechnology is available whereby a portion of the main fuel stream is ignited internally in the burnerbarrel using oil, gas or plasma. The technology necessitates adjustments in operations methodologyfor proper function. A task group comprised of members from BCS-MBB has studied this technology.This paragraph, in conjunction with other proposed paragraphs, addresses that new technology.

Substantiation

The proposed code revision will provide minimum safety requirements of a new technology that canenable US coal fired power plants to respond to real time market conditions in a timely manner. Thetechnology is desirable because it reduces, or eliminates, the amount of premium support fuel usedto warm up a boiler and to bring on successive mill groups.

The technology has been successfully applied outside the US with installations in over 1,000 coalfired boilers in both the plasma and oil igniter form; and is available from multiplesuppliers/manufacturers. These installations have helped determine the suitability of the technologyfor US plants and give confidence in its safety potential. To enhance user safety the system is beingproposed as a new igniter classification (a “Special” derivative of the existing Class II) which requiresthe usage to be under defined conditions only.

The key distinguishing characteristic between the igniter classes in the NFPA 85 code is thedifference in igniter ability to tolerate process variations. Based on the igniter ability to function underdifficult conditions, the implementation and the privileges of the igniter class vary. Whereas Class Ican be used under “all credible” conditions (3.3.73.1), Class II can be used under “prescribed”(3.3.73.2) light off conditions only.

The restriction to prescribed conditions is also required due to the difficulty in igniter flame proving in


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some of these applications for the plasma igniters form. The location of the igniter flame inside theburner barrel, where it cannot be reliably sensed with existing flame proving technologies, requiresthe use of a proven main burner flame under non initial start-up conditions for safe operation.

This revision will help avoid unsafe application of this new technology by providing clear andconsistent minimum safety requirements.

ResponseMessage:




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* Concentrated Flame IgntiterAn integrated burner-igniter system that utilizes either oil or gas to raise the pulveized coal stream to itsautoignition temperature.




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Committee Statement

CommitteeStatement:


---

Problem Statement


Substantiation




The restriction to prescribed conditions is also required due to the difficulty in igniter flame proving insome of these applications for the plasma igniters form. The location of the igniter flame inside the


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burner barrel, where it cannot be reliably sensed with existing flame proving technologies, requiresthe use of a proven main burner flame under non initial start-up conditions for safe operation.


ResponseMessage:




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3.3.73.xx * Plasma Arc IgniterAn integrated burner-igniter system that utilizes high temperature ionized gas to rapidly fracture coalparticles and ignite volatiles, as part of an integrated burner-igniter system.




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Committee Statement

CommitteeStatement:


---

Problem Statement


Substantiation




The restriction to prescribed conditions is also required due to the difficulty in igniter flame proving insome of these applications for the plasma igniters form. The location of the igniter flame inside the


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burner barrel, where it cannot be reliably sensed with existing flame proving technologies, requiresthe use of a proven main burner flame under non initial start-up conditions for safe operation.


ResponseMessage:




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First Revision No. 104-NFPA 85-2017 [ New Section after 3.3.76 ]

3.3.76.1 Permissive.

An interlock that functions only to allow initiation of the operation of equipment or a subsequent function.




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Committee Statement

CommitteeStatement:

The definition for permissive has been revised to better represent how the term is usedthroughout the document. Additional First Revisions have been made to make usage consistent.

Public Input No. 28-NFPA 85-2016 [New Section after 3.3.76]


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3.3.76.2 Trip.

An interlock that shuts down equipment when a predefined set of conditions exists.




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Committee Statement

CommitteeStatement:

The definition for trip has been revised to better represent how the term is used throughout thedocument. Additional First Revisions have been made to make usage consistent.

ResponseMessage:



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3.3.76 Interlock.

A device, or an arrangement of devices, in which function which prevents, limits, stops, or initiates theoperation of one part or one mechanism of the device or arrangement controls the operation of anotherpart of another mechanism equipment or a subsequent function.

A.3.3.76

An interlock can consist of a sensing function, a control function, and an output or a final control element. The interlock can be accomplished with the use of any combination of electrical devices, mechanicaldevices, or logic .




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Committee Statement

CommitteeStatement:

The definition for interlock has been revised to better represent how the term is used throughoutthe document. Additional First Revisions have been made to make usage consistent.



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3.3.94 Permissive.

See 3.3.76.1.




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Committee Statement

CommitteeStatement:

The definition for permissive has been added (3.3.76.1) to better represent how the term is usedthroughout the document. Additional First Revisions have been made to make usage consistent.

ResponseMessage:



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3.3.119 Shutdown.

3.3.119.1 Combustion Turbine Normal Shutdown.

The normal sequence of events that automatically provides successful shutdown of the combustion turbinewith no abnormal conditions in the combustion system.

3.3.119.2 Normal Shutdown.

Stopping burner operation by shutting off all fuel and ignition energy to the combustion equipment.

3.3.119.3 Safety Shutdown (Single Burner Boiler).

Stopping burner operation by shutting off all fuel and ignition energy to the furnace.




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Committee Statement

CommitteeStatement:

The definition for Combustion Turbine Normal Shutdown contains requirements, which areprohibited in definitions by the NFPA Manual of Style. Language should be added to Chapter 8 tomaintain the requirement for no abnormal conditions prior to establishing purge credit.

The definition for Normal Shutdown is redundant to requirements already included in theequipment-specific chapters where normal shutdown sequences are described in detail.

The Single Burner Boiler definition for Safety Shutdown describes a Master Fuel Trip, which isdefined. The SBB Technical Committee can submit Public Comments on this action as they deemnecessary.

ResponseMessage:



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3.3.127 Transmitter.

Any device that converts process measurements from a sensor into a variable signal to be received by adisplay, control, or protective device interlock .




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Committee Statement

Committee Statement: This revision aligns with the revised definition for interlock (FR 103).

Response Message:



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3.3.129 Trip.

See 3.3.76.2.




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Committee Statement

CommitteeStatement:

The definition for trip has been added (3.3.76.2) to better represent how the term is usedthroughout the document. Additional First Revisions have been made to make usage consistent.

ResponseMessage:



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3.3.132.8 * Safety Shutoff Valve (Safety Trip Valve).

A An automatic fast-closing valve that automatically shuts off the gaseous or liquid fuel supply in responseto a normal, emergency, or safety shutdown signal. shutdown or trip signal.

A.3.3.132.8 The actua on values and me of ac on of the ini a on devices should be tuned to the furnace and

equipment on which they are installed. The me required for closing the valve should be selected to minimize the

possibility of equipment damage due to closing forces and hydraulic shock associated with rapid closure of large‐

diameter valves. Subject specific chapters must be consulted to determine if a specific me frame for valve closure

is required.




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Committee Statement

CommitteeStatement:

The types of shutdown signals were removed to be consistent with FR 105 which defines trip,and FR 112 that removes the definition of safety shutdown.

Annex material was added to clarify the term fast-closing and to signal to the user of the codethat other chapters should be referenced for specific closing speeds.

ResponseMessage:


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Committee Input No. 153-NFPA 85-2017 [ New Section after 4.1 ]

A task group will be created at the end of this cycle to look at common requirements that can potentially bemoved to Chapter 4 in the next cycle. The Fundamentals Committee will be looking for Task Groupvolunteers from all BCS Committees.




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Committee Statement

CommitteeStatement:

A task group will be created at the end of this cycle to look at common requirements that canpotentially be moved to Chapter 4 in the next cycle. The Fundamentals Committee will be lookingfor Task Group volunteers from all BCS Committees.

ResponseMessage:

Public Input No. 172-NFPA 85-2016 [New Section after 4.1]


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4.2.4

The interlock system and protective devices shall interlocks and associated devices shall be tested jointlyby the organization responsible for the system design and by those who operate and operate or maintainsuch a system and devices .




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Committee Statement

CommitteeStatement:

This revision aligns with the revised definition for interlock (FR 103). Interlock system waspreviously undefined.

ResponseMessage:



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Committee Input No. 154-NFPA 85-2017 [ New Section after 4.3.2 ]

4.3.3* The owner or fuel provider shall specify the lowest Autoignition Temperature (AIT) for all fuels firedin the boiler and/or combustion system over the range of the expected operating conditions taking intoconsideration fuel composition, pressure and oxygen concentration.

A.4.3.3 Autoignition temperatures for various materials can be found in Table 4.4.2 of 2017 NFPA 497,Recommended Practice for the Classification of Flammable Liquids, Gases, or Vapors and of Hazardous(Classified) Locations for Electrical Installations in Chemical Process Areas. The value of autoignitiontemperature depends on the method of testing. The data provided NFPA 497 was developed usinginternationally accepted test methods. If a particular material is not included in this document, the dataobtained in a similar apparatus described by ASTM E659, Standard Test Method for AutoignitionTemperature of Liquid Chemicals, can be used.




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Committee Statement

CommitteeStatement:

There are numerous instances in Chapter 8 as well as in Chapter 6 that reference AutoignitionTemperature (AIT).

Natural gas is usually a mixture of various gases, with the primary component being methane. Asearch of the internet for “the Auto-ignition Temperature of Natural gas” gave the AIT of natural gas(methane) to be 580°C. NFPA 497 did not specify an AIT for natural gas but gave 600°C formethane. Additionally, many HRSG’s are in refinery service that can use “refinery” gas in thecombustion turbine and/or the duct burner where the AIT can vary depending on the blend.

ResponseMessage:


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4.3.2*

The integration of the various components, including boiler or HRSG, burner, fuel and air supply equipment,controls, interlocks and safety and associated devices, operator and maintenance functions, andcommunication and training, shall be the responsibility of the owner and the operating company.




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Committee Statement

CommitteeStatement:

This revision aligns with the revised definition for interlock (FR 103). Safety devices areundefined.



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4.5.5

Interlock devices shall Interlocks shall be permitted to be temporarily removed from service in accordancewith the following:

(1) Removal of the interlock shall be authorized by a competent person and documented in accordancewith operating procedures.

(2) Alternate means shall be substituted to supervise this the interlock function in accordance withoperating procedures.




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Committee Statement

CommitteeStatement:

This revision aligns with the revised definition for interlock (FR 103). Interlock devices areundefined.

Response Message:



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4.7.7* Ignition Subsystem.

The ignition subsystem shall meet the requirements of 4.7.7.1 through 4.7.7.13.

4.7.7.1

The ignition subsystem shall be sized and arranged to ignite the main burner input within the limitation ofthe igniter classification as follows:

(1) It shall be verified through testing that the igniters furnished meet the requirements of the classspecified in the design.

(2) Igniters shall be designated as Class 1, Class 2, or Class 3 as defined in 3.3.73.1, 3.3.73.2, and3.3.73.3 and as verified by test.

4.7.7.2

Class 1 igniters shall be permitted to be used as Class 2 or Class 3 igniters. Class 2 igniters shall bepermitted to be used as Class 3 igniters.

4.7.7.3

Where Class 2 igniters are used, the burner shall be operated under controlled conditions to limit thepotential for abnormal operation, as well as to limit the charge of fuel in the event that ignition does notoccur during light-off.

4.7.7.4

Class 2 igniters shall not be used to ignite the main fuel under uncontrolled or abnormal conditions.

4.7.7.5

Where Class 3 igniters are used, the igniter shall be turned off as a part of the burner light-off procedurewhen the time trial for ignition of the main burner has expired, to ensure that the main flame is notdependent on ignition support from the igniter.

4.7.7.6

Class 2 igniters shall not be used to extend the turndown range but shall be permitted to be used tosupport ignition under low-load or adverse operating conditions.

4.7.7.7

Class 3 igniters shall not be used to support ignition or to extend the burner turndown range.

4.7.7.8

Except for periods when the main burner is being scavenged, Class 3 special igniters shall not be usedunless supervision of the individual main burner flame is provided.

4.7.7.9*

Where Class 1 and Class 2 igniters are used, the tests described in 6.6.3.2.2, 6.7.3.2.2, and 6.8.3.2.2shall also be performed with the ignition subsystem in service to verify that the igniters furnished meet therequirements of the class specified in the design.

4.7.7.10

Tests shall be performed to determine transient limits in the ignition air and fuel supplies or in the main airand fuel supplies that do not extinguish the igniter flame or reduce the igniter's ability to perform itsintended function or adversely affect other burners and igniters in operation.


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4.7.7.11

Igniters shall be permanently installed under the following conditions:

(1) They shall be supervised to verify that the requirements of 4.7.7.1 and 4.7.7.2 are met.

(2) This supervision shall include igniter capacity and individual igniter flame monitoring.

(3) The capacity shall be measured by igniter header pressure as a minimum.

(4) On single burner boilers, igniters shall not require supervision of igniter capacity.

4.7.7.12

The ignition equipment shall be located in an environment free of excessive heat and accessible formaintenance.

4.7.7.13

All igniter safety shutoff valves shall be located to minimize the volume of fuel that is downstream of thevalve in the individual igniter fuel lines or that could flow by gravity into the combustion chamber after anemergency shutdown or a burner shutdown.




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Committee Statement

CommitteeStatement:

The submitter of PI 133 has raised an important issue that illustrated differing interpretations ofthe material and allowances in 4.7.7 as a whole. A Task Group has been formed to review thissection and submit Public Comments.

ResponseMessage:



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4.7.7.1

The ignition subsystem shall be sized and arranged to ignite the main burner input within the limitation ofthe igniter classification as follows:

(1) It shall be verified through testing that the igniters furnished meet the requirements of the classspecified in the design.

(2) Igniters shall be designated as Class 1, Class 2, Class 3 or Class 3 Special as defined in 3.3.73.1,3.3.73.2, and 3.3.73.3 and 3.3.73.4 and as verified by test.




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Committee Statement

CommitteeStatement:

4.7.7.1(2) as currently written would not allow the use of a "Class 3 Special Igniter" as a validIgnition Subsystem, although later in the paragraph (4.7.7.8) restrictions/conditions are given forthe use of a Class 3 Special Igniter.

ResponseMessage:



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Committee Input No. 142-NFPA 85-2017 [ Section No. 4.7.7.10 ]

4.7.7.10 *

Tests shall be performed to determine transient limits in the ignition air and fuel supplies or in the main airand fuel supplies that do not extinguish the igniter flame or reduce the igniter's ability to perform its intendedfunction or adversely affect other burners and igniters in operation.

A.4.7.7.10 The Class 1 igniter design, and associated test plan, should address all credible combinationsof main burner inputs via first stating the high and low limits of those burner inputs, and then testing allcredible combinations of those burner input limits, including at least:

(1) Range of ultimate and proximate analyses of fuels to be fired

(2) Range of heat input from burner minimum to burner maximum

(3) Range of pulverized fuel product fineness entering the burners

(4) Range of coal/air (primary air) temperature entering the burner nozzle from the coal conduit

(5) Range of secondary air temperature

(6) Range of burner stoichiometric ratio, or burner air-to-fuel ratio




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CommitteeStatement:

Currently, there is no guidance on what type of tests need to be performed to verify the igniterclassification. This CI is to provides a starting point to review the issue. Public Comments areencouraged.

ResponseMessage:




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4.7.7.13

All igniter safety shutoff valves shall be located to minimize the volume of fuel that is downstream of thevalve in the individual igniter fuel lines or that could flow by gravity into the combustion chamber after anemergency shutdown or a burner shutdown.




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Committee Statement: This is a concern for any type of shutdown, not just an emergency or burner shutdown.

Response Message:



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First Revision No. 155-NFPA 85-2017 [ New Section after 4.10.1.1 ]

4.10.1.2 Overpressure Protection.

4.10.1.2.1

Overpressure protection shall be provided in either of the following cases:

(1) When the supply pressure exceeds the pressure rating of any downstream component

(2) When the failure of a single upstream line regulator or service pressure regulator results in a supplypressure exceeding the pressure rating of any downstream component

4.10.1.2.2

Overpressure protection shall be provided by any one of the following:

(1) A series regulator in combination with a line regulator or service pressure regulator

(2) A monitoring regulator installed in combination with a line regulator or service pressure regulator

(3)* A full-capacity pressure relief valve

(4) An overpressure cutoff device, such as a slam-shut valve or a high-pressure switch in combinationwith an adequately rated shutoff valve

4.10.1.2.3

When a relief valve is used to comply with 4.10.1.2.1 , the relief valve shall be a full-capacity relieftype.

4.10.1.2.4

Token relief valves and internal token relief valves shall not be permitted to be used as the onlyoverpressure protection devices.

4.10.1.2. 5 * Setpoint of the Overpressure Protection Device.

The overpressure protection device shall be set to provide a maximum downstream pressure as follows:

(1) When the rated pressure of any component is less than 12 psi (83 kPa), the set point of theoverpressure protection device shall not exceed 150 percent of the rated pressure of the lowest ratedcomponent.

(2) When the rated pressure of any component is equal to or greater than 12 psi (83 kPa) but less than 60psi (414 kPa), the set point of the overpressure protection device shall not exceed 6 psi (41 kPa) above therated pressure of the lowest rated component.

(3) When the rated pressure of any component is equal to or greater than 60 psi (414 kPa), the set point ofthe overpressure protection device shall not exceed 110 percent of the rated pressure of the lowest ratedcomponent.

A.4.10.1.2.2 (3 )

Upon upstream pressure regulation failure, a full-capacity pressure relief valve (versus token relief valves)will limit the downstream pressure. Token relief valves only provide minimum pressure relief in cases whereambient temperatures increase the pressure inside the gas piping, which can occur during shutdownperiods, or relieves small increases of pressure due to high lockup pressures that occur during a shutdown.


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A.4.10.1.2.5 The pressure limits in this section are consistent with 49 CFR Part 192.201,

Required Capacity of Pressure Relieving and Limiting Stations




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CommitteeStatement:

Overpressure protection is a common element in multiple subject chapters, therefore theFundamentals committee is moving it forward to Chapter 4. In addition, detail was added to clarifyapplication of overpressure protection and methods to achieve it.

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4.11.1 Interlock System Interlocks .

4.11.1.1

The basic requirement of an interlock system for a boiler or combustion system shall accomplish thefollowing interlocks shall :

(1) Protect personnel from injury

(2) Protect equipment from damage

(3) Protect operation by limiting actions to a prescribed operating sequence or by initiating a trip deviceswhen approaching an out-of-range or unstable operating condition

4.11.1.2*

Additional automatic trips interlocks shall be permitted.

4.11.1.3

Fuel-specific interlocks shall be provided for each design basis fuel.

4.11.1.4*

Operating personnel shall be made aware of the limitations of the interlock system interlocks .




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CommitteeStatement:

This revision aligns with the updated and new definitions for interlock and trip. Interlocksystems are undefined.

ResponseMessage:



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4.11.4

The burner management system interlock interlocks and alarm functions shall alarms shall be initiated byone or more of the following:

(1) One switch or transmitter dedicated to the burner management system

(2) Voting logic derived from two or more switches or transmitters

4.11.4.1 (a)

When multiple transmitters are used in the burner management system, such signals shall be permitted tobe shared with other control systems for control purposes.

4.11.4.2 (b) *

When signals from multiple switches or transmitters are provided to initiate interlock interlocks or alarmfunctions alarms , those signals shall be monitored in comparison to each other by divergence or other faultdiagnostic alarms.

4.11.4.3 (c)

When signals from multiple switches or transmitters are provided to initiate interlock interlocks or alarmfunctions alarms , the provided signals shall be generated by individual sensing devices connected toseparate process taps.




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Committee Statement

CommitteeStatement:

This revision aligns with the revised definition of interlock (FR 103).

The section was restructured because there was confusion about how they were to be applied.4.11.4.1 through 4.11.4.3 apply to the second list item under 4.11.4.

ResponseMessage:




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4.11.8.2

The burner management safety functions system shall include but shall not be limited to purge interlocksand timing, mandatory safety shutdowns, trial timing for ignition, and all required interlocks and flamemonitoring.




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Committee Statement

CommitteeStatement:

Safety functions were undefined, and there was some confusion around the shall/shall notlanguage. This revision clarifies what is intended for the independent burner managementsystem.

ResponseMessage:



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4.11.9 Momentary Closing of Fuel Valves.

4.11.9.1

Logic sequences or devices intended to cause a safety shutdown, once initiated, shall cause a burner orA burner trip, fuel trip, or master fuel trip , as applicable, and shall require operator action prior to resumingoperation of the affected burner(s).

4.11.9.2 *

No logic sequence or device shall be permitted that allows momentary full closing and subsequentinadvertent reopening of the main or ignition fuel valves.

A.4.11.9.2 This is not meant to apply to partial stroke testing of fuel valves.




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CommitteeStatement:

This revision aligns with the new definition of trip (FR 105). It also removes the unenforceableterm "momentary" and clarifies the application of 4.11.9.2 with annex material.

ResponseMessage:



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4.11.11 Documentation.

Documentation shall be provided to the owner and the operator indicating that all safety devices and logicmeet the the Burner Management System meets the requirements of the application.




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CommitteeStatement:

Safety devices are undefined. Safety devices and logic are all part of the burnermanagement system.

Response Message:



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4.12.1 Functional Requirements.

The basic requirements of any flame monitoring and tripping system shall be as follows:

(1) Combustion instability situations shall be brought to the attention of the operator for remedial action.

(2) An emergency shutdown A trip of the involved equipment shall be automatically initiated upondetection of serious combustion problems that will lead to the accumulation of unburned fuel.




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Committee Statement

Committee Statement: This revision aligns with the new definition for trip created by FR 105.

Response Message:



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4.12.2 System Objectives.

4.12.2.1

System objectives shall be developed and documented that include those requirements that arespecifically related to the combustion conditions typical for particular combustion chamber configurations,burner or firing systems, and fuel characteristics.

4.12.2.2

Such objectives shall be consistent with the individual manufacturer's design philosophy.




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CommitteeStatement:

The revision has added a requirement to document the objectives to make this sectionenforceable.

Response Message:



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First Revision No. 125-NFPA 85-2017 [ Sections 4.13.2.1, 4.13.2.2 ]

Sections 4.13.2.1, 4.13.2.2

4.13.2.1*

Except as noted in 4.13.2.2 , under no circumstances shall airflow demand Airflow demand shall not beless than the minimum purge rate established by the designer.

4.13.2.2

For single burner boilers, airflow demand shall not be reduced below the low limit of the fuel-burningsystem as determined by the burner manufacturer and verified by operating test.




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Committee Statement

CommitteeStatement:

To better organize the document, this exception should be addressed by SBB in Chapter5.

Response Message:

Public Input No. 45-NFPA 85-2016 [Sections 4.13.2.1, 4.13.2.2]


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First Revision No. 126-NFPA 85-2017 [ Sections 4.13.3.3.1, 4.13.3.3.2 ]

Sections 4.13.3.3.1, 4.13.3.3.2

4.13.3.3.1

Except as noted in 4.13.3.3.2 , automatic Automatic control of the fuel input(s) shall not be permittedunless the airflow is maintained in automatic control.

4.13.3.3.2

For HRSGs designed and operated in accordance with Chapter 8 , automatic control of fuel inputs shallbe permitted without automatic control of airflow.




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Committee Statement

CommitteeStatement:

To better organize the document, this exception should be addressed by HRS in Chapter8.

Response Message:

Public Input No. 46-NFPA 85-2016 [Sections 4.13.3.3.1, 4.13.3.3.2]


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4.13.3.5

The combustion control system shall not reduce the fuel feed to a pulverizer below the minimum feed rateestablished by the pulverizer manufacturer for the manufacturer's specified design fuel.

4.13.3.5.1

For fuels with ignition characteristics different from those of the manufacturer's design fuel, the combustioncontrol system shall not reduce the fuel feed rate below the value that ensures stable and self-sustainingcombustion at the burners served by the pulverizer.

4.13.3.5.2

The minimum feed rate for fuels not conforming to the fuel specifications used by the manufacturer in thedesign of the pulverizer system shall be determined by operational tests.




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Committee Statement

CommitteeStatement:

To better organize the document, the FUN TC has proposed that this topic should beaddressed by MBB in Chapter 6.

ResponseMessage:



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First Revision No. 128-NFPA 85-2017 [ Section No. 4.14 ]

4.14 Power Supplies.

Precautions shall be taken to ensure the availability of a failure-free power supply (electric or pneumatic) toall control and safety devices burner management system components .




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Committee Statement

Committee Statement: Safety devices are undefined. This revision clarifies the applicability of the requirement.

Response Message:

Public Input No. 48-NFPA 85-2016 [Section No. 4.14]


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4.15.1

Except as noted in 4.15.1.1 and 4.15.1.2 , continuous Continuous trend display of steam flow rate,feedwater flow rate, total fuel flow rate, and total airflow rate as a percentage of the maximum unit load,drum level or waterwall flow as applicable , final steam temperature, main steam pressure, and furnace orcombustion chamber draft shall be simultaneously available at the operating location.

4.15.1.1 *

For single burner boilers, continuous trend display of operating parameters critical to operation shall beprovided.

4.15.1.2

For HRSGs, continuous trend display requirements are specified in 8.7.2.3 .




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Committee Statement

CommitteeStatement:

To better organize the document, these exceptions should be addressed by SBB in Chapter 5and by HRS in Chapter 8, including the associated Annex material.

Waterwall flow was added because not all boilers covered will have a drum level.

ResponseMessage:


Public Input No. 55-NFPA 85-2016 [Section No. A.4.15.1.1]


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First Revision No. 130-NFPA 85-2017 [ Section No. A.1.2.1 ]

A.1.2.1

Combustion explosions involve several considerations. The basic cause of uncontrolled fires or combustionexplosions is the ignition of an accumulated combustible mixture within the confined space of a furnace, aHRSG, or a pulverizer or the associated passes, ducts, and fans that convey the gases of combustion tothe stack.

A dangerous combustible mixture within the boiler, HRSG, or pulverizer enclosure consists of theaccumulation of an excessive quantity of combustibles mixed with air in proportions that result in rapid oruncontrolled combustion when an ignition source is supplied. An explosion can result from ignition of thisaccumulation if the quantity of combustible mixture and the proportion of air to fuel are such that anexplosive force is created within the enclosure. The magnitude and the intensity of the explosion depend onboth the relative quantity of combustibles that has accumulated and the proportion of air that mixes with thecombustibles at the moment of ignition. Explosions, including “puffs,” are the result of improper operatingprocedures by personnel, improper design of equipment or control systems, or malfunction of theequipment or control system.

Numerous conditions can arise in connection with the operation of a system that produce explosiveconditions. The most common of these are as follows:

(1) An interruption of the fuel or air supply or ignition energy sufficient to result in momentary loss offlames, followed by restoration and delayed reignition of an accumulation

(2) Fuel leakage into an idle combustion chamber and the ignition of the accumulation by a spark or othersource of ignition

(3) Repeated unsuccessful attempts to light off without appropriate purging, resulting in the accumulationof an explosive mixture

(4) The accumulation of an explosive mixture of fuel and air as a result of loss of flame or incompletecombustion and the ignition of the accumulation by a spark or other ignition source, such as couldoccur when an attempt is made to relight a burner(s)

(5) Purging with an airflow that is too high, which stirs up smoldering combustible materials

The listed conditions favorable to an explosion are typical examples, and an examination of numerousreports of explosions suggests that the occurrence of small explosions, puffs, or near misses has been farmore frequent than usually is recognized. It is believed that improved instrumentation, safety interlocks andprotective associated devices, proper operating sequences, and a clearer understanding of the problem byboth designers and operators can greatly reduce the risks and actual incidence of explosions.

In a boiler or a HRSG, upset conditions or control malfunction can lead to an air-fuel mixture that couldresult in a flameout followed by reignition after a combustible air-fuel ratio has been re-established.

Dead pockets might exist in a pulverized fuel system or in a boiler or HRSG enclosure or other parts of theunit, where combustible mixtures can accumulate under upset conditions. These accumulations could ignitewith explosive force in the presence of an ignition source.

Furnace or HRSG implosions involve another set of considerations. An implosion is the result of theoccurrence of excessively low gas side pressure, which causes equipment damage. Two conditions thathave caused implosions follow:

(1) A maloperation of the equipment that regulates the gas flow, including air supply and flue gasremoval, resulting in exposure to excessive induced draft fan head capability

(2) The rapid decay of gas temperatures and pressure resulting from either a rapid reduction in fuel inputor a master fuel trip

A combination of the two listed conditions has resulted in severe implosion incidents.



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Committee Statement

Committee Statement: This revision aligns with the updated definition of interlock.

Response Message:

Public Input No. 50-NFPA 85-2016 [Section No. A.1.2.1]


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A.3.3.25 Burner Management System.

The burner management system can include the following functions as specified in this code: interlocksystem interlocks , fuel trip system, master fuel trip system, master fuel trip relay, flame monitoring andtripping systems, ignition subsystem, main burner subsystem, warm-up burner subsystem, bed temperaturesubsystem, and duct burner system.




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Committee Statement

CommitteeStatement:

This revision aligns with the revised definition for interlock (FR 103). Interlock system waspreviously undefined.

ResponseMessage:



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First Revision No. 132-NFPA 85-2017 [ Section No. A.4.4.1.1 ]

A.4.4.1.1

An example of an inspection and maintenance schedule is as follows:

(1) Daily: flame failure detection system, low water level cutout, and alarm

(2) Weekly: igniter and burner operation

(3) Monthly: fan and airflow interlocks interlock device(s) , fuel safety shutoff valves for leakage, highsteam pressure interlock device(s) , fuel pressure and temperature interlocks interlock device(s) forfuel oil, high and low fuel pressure interlocks interlock device(s) , and fuel gas strainer and drip leg

(4) Semiannually: burner components; flame failure system components; piping, wiring, and connectionsof all interlocks and interlock devices and shutoff valves; calibration of instrumentation andcombustion control system




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Committee Statement

CommitteeStatement:

The definition of interlock revised by FR 103 indicates that interlocks are functions. The intentof this section is to inspect physical components.

ResponseMessage:



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First Revision No. 133-NFPA 85-2017 [ Section No. A.4.4.1.3 ]

A.4.4.1.3

When a system includes a built-in test mechanism that bypasses any safety device, it should beinterlocked interlock, the test mechanism should be designed to prevent operation of the system while thedevice is in the test mode, unless operation procedures specifically address this device or it is listed for thatpurpose.




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Committee Statement: Safety devices are not defined. This revision aligns with the revised definition of interlock.

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A.4.11.7

Logic systems include, among others, programmable logic controllers (PLCs), digital processing units(DPUs process automation controllers (PACs ), and and distributed control systems (DCSs).




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Committee Statement

CommitteeStatement:

The term "digital processing units (DPUs)" is an old term that is rarely used and is not foundanywhere else in NFPA 85. PACs have come on the market over the last decade or so and are asort of a cross between PLCs and DCSs. This change to the Annex text would better reflect thecurrently available system technologies that might be utilized to implement burner managementsystems.

ResponseMessage:



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First Revision No. 134-NFPA 85-2017 [ Section No. A.4.13 ]


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A.4.13


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Users of this code are encouraged to use judgment in the application of the following guidelines for allprocess and safety functions contained in a distributed control system.

(1) For data transmission, the following should be considered:

(2) Every input should be sampled at intervals of no more than 1 second. Every output should beupdated at intervals of no more than 1 second.

(3) For protective actions, the system should be able to convert a changed input sensor value to acompleted output control action in 250 milliseconds or less.

(4) Changes in displayed data or status should be displayed within 5 seconds.

(5) Data acquisition and transmission systems should be protected from noise pickup andelectrical interference.

(6) In redundant systems, the data links should be protected from common mode failures. Wherepracticable, redundant data links should be routed on separate paths to protect against physicaldamage that disables both data links.

(7) For hardware, the following should be considered:

(8) The hardware selected should have adequate processor capacity to perform all the functionsrequired for start-up sequencing, normal operation alarming, monitoring, and shutdown of thecontrolled equipment. Capacity also should be available for data storage and sorting; thiscapacity can be permitted to be located in a separate processor.

(9) Selection should take into consideration the requirements for reliability, maintainability, andelectrical classification.

(10) The hardware should provide for automatic tracking between automatic and manual functionsto allow for immediate seamless transfer.

(11) The hardware should be capable of stable dynamic control.

(12) The hardware should be capable of thorough self-diagnosis.

(13) Consideration should be given to all levels and types of electrical interference that can betolerated by the hardware without compromising its reliability or effectiveness.

(14) Fail-safe operation should be obtained through a thorough and complete analysis of eachcontrol loop and by providing for a failure of that loop (i.e., valve/actuator) to cause a fail-safeposition.

(15) For software, the following should be considered:

(16) The software package should be designed to include all logic to provide a safe and reliablecontrol system. When the software calls for the operation of a

field safety device

(a) final control element , a feedback signal should be provided to prove that the requestedoperation has taken place, and an alarm should be actuated if the action is not confirmed in aspecified amount of time.

(b) The software package should be checked to ensure that no unintended codes or commandsare present (e.g., viruses or test breaks). The software package should be tested and practicedbefore being loaded into the plant site computers or processors.

(c) The software system should be protected from inadvertent actions by operators and should betamperproof.

(d) Written procedures should specify the functions that can and cannot be accessed by theoperator and those functions that require additional authorization for access.

(e) The software should be permitted to provide for authorized on-line changes of the timers andset points, provided the safety of the operating equipment is not compromised.

(f) The software should implement and enhance the self-diagnostic hardware.


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Street Address:

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Committee Statement

Committee Statement: Safety device is undefined and final control element is a generally understood term.

Response Message:

Public Input No. 54-NFPA 85-2016 [Section No. A.4.13]


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Committee Input No. 152-NFPA 85-2017 [ Chapter K ]

Annex K Informational References

K.1 Referenced Publications.

The documents or portions thereof listed in this annex are referenced within the informational sections ofthis code and are not part of the requirements of this document unless also listed in Chapter 2 for otherreasons.

K.1.1 NFPA Publications.

National Fire Protection Association, 1 Batterymarch Park, Quincy, MA 02169-7471.

NFPA 30, Flammable and Combustible Liquids Code, 2015 edition.

NFPA 31, Standard for the Installation of Oil-Burning Equipment, 2011 edition.

NFPA 51, Standard for the Design and Installation of Oxygen–Fuel Gas Systems for Welding, Cutting, andAllied Processes, 2013 edition.

NFPA 51B, Standard for Fire Prevention During Welding, Cutting, and Other Hot Work, 2014 edition.

NFPA 54, National Fuel Gas Code, 2015 edition.

NFPA 56, Standard for Fire and Explosion Prevention During Cleaning and Purging of Flammable GasPiping Systems, 2014 edition.

NFPA 58, Liquefied Petroleum Gas Code, 2014 edition.

NFPA 68, Standard on Explosion Protection by Deflagration Venting, 2013 edition.

NFPA 69, Standard on Explosion Prevention Systems, 2014 edition.

NFPA 70 ®, National Electrical Code ®, 2014 edition.

NFPA 77, Recommended Practice on Static Electricity, 2014 edition.

NFPA 85, Boiler and Combustion Systems Hazards Code, 2007 edition.

NFPA 85, Boiler and Combustion Systems Hazards Code, 2011 edition.

NFPA 241, Standard for Safeguarding Construction, Alteration, and Demolition Operations, 2013 edition.

NFPA 497, Recommended Practice for the Classification of Flammable Liquids, Gases, or Vapors and ofHazardous (Classified) Locations for Electrical Installations in Chemical Process Areas, 2012 edition.

NFPA 499, Recommended Practice for the Classification of Combustible Dusts and of Hazardous(Classified) Locations for Electrical Installations in Chemical Process Areas, 2013 edition.

NFPA 850, Recommended Practice for Fire Protection for Electric Generating Plants and High VoltageDirect Current Converter Stations, 2015 edition.

K.1.2 Other Publications.

K.1.2.1 ABMA Publications.

American Boiler Manufacturers Association, 8221 Old Courthouse Road, Suite 202 380 , Vienna, VA22182–3839 22182 .

ABMA 203, A Guide to Clean and Efficient Operation of Coal-Stoker-Fired Boilers, 2002.

ABMA 307, Combustion Control Guidelines for Single Burner Firetube and WatertubeIndustrial/Commercial/Institutional Boilers, 1999.

K.1.2.2 AlChE Publications.

American Institute of Chemical Engineers, 120 Wall Street, FL 23, New York, NY 10005-4020.

Guidelines for Hazard Evaluation Procedures, 2008.


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K.1.2.3 API Publications.

American Petroleum Institute, 1220 L Street, NW, Washington, DC 20005-4070.

API STD 620, Standard for Design and Construction of Large, Welded, Low-Pressure Storage Tanks,2009 2013 .

API STD 650, Standard for Welded Steel Tanks for Oil Storage, 2008 2013 .

API RP 500, Recommended Practice for Classification of Locations for Electrical Installations at PetroleumFacilities Classified as Class I, Division 1 and Division 2, 1998 (reaffirmed 2002) 2012 .

API RP 505, Recommended Practice for Classification of Locations for Electrical Installations at PetroleumFacilities Classified as Class I, Zone 0, Zone 1, and Zone 2, 1997 (reaffirmed 2002 2013 ).

API RP 2003, Recommended Practice for Protection Against Ignitions Arising Out of Static, Lightning, andStray Currents, 2008 2015 .

K.1.2.4 ASME Publications.

American Society of Mechanical Engineers, Two Park Avenue, New York, NY 10016-5990.

ASME Boiler and Pressure Vessel Code, 2007 2015 .

K.1.2.5 ASTM Publications.

ASTM International, 100 Barr Harbor Drive, P.O. Box C700, West Conshohocken, PA 19428-2959.

ASTM D409/D409M , Standard Test Method for Grindability of Coal by the Hardgrove-Machine Method,2012 2016 .

ASTM D396, Standard Specification for Fuel Oils, 2009 2016 .

ASTM E1226, Standard Test Method for Explosibility of Dust Clouds, 2010 2012a .

K.1.2.6 EEMUA Publications.

The Engineering Equipment and Material Users Association, 63 Mark Lane, London UK EC3R 7NQ.

EEMUA Publication 191, Alarm Systems — A Guide to Design, Management, and Procurement, 20072013 .

K.1.2.7 IEC Publications.

International Electrotechnical Commission, 3, rue de Varembé, P.O. Box 131, CH-1211 Geneva 20,Switzerland.

IEC 61511, Functional Safety — Safety Instrumented Systems for the Process Industry Sector, 2003.

K.1.2.8 ISA Publications.

International Society of Automation, 67 T. W. Alexander Drive, Research Triangle Park, NC 27709.

ANSI/ISA 18.2,Management of Alarm Systems for the Process Industries, 2009.

ANSI/ISA 77.41.01, Fossil Fuel Power Plant Boiler Combustion Controls, 2005 2015 .

ANSI/ISA 77.42.01, Fossil Fuel Power Plant Feedwater Control System — Drum Type, 1999(R2006 reaffirmed 2011 ).

ANSI/ISA 77.43.01, Fossil Fuel Power Plant Unit/Plant Demand Development — Drum Type, 2002(R2008) , 2014 .

ANSI/ISA 77.44.01, Fossil Fuel Power Plant — Steam Temperature Controls, 2007 (reaffirmed 2013) .

ANSI/ISA 84.00.01, Application of Safety Instrument Systems for the Process Industry, 2004.

ISA TR18.2.4, Enhanced and Advanced Alarm Methods, 2012

ISA TR18.2.5, Alarm System Monitoring, Assessment, and Auditing, 2012.

K.2 Informational References.

The following documents or portions thereof are listed here as informational resources only. They are not apart of the requirements of this document.


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K.2.1 Additional HRSG References.

The following documents provide additional information on iron fires.

Johnson, A. A., J. A. Von Franuhofer, and E. W. Jannett,“Combustion of Finned Steel Tubing During StressRelief Heat Treatment,” Journal of Heat Treating, Vol. 4, No. 3, June 1986, pp. 265–271.

McDonald, C. F., “The Potential Danger of Fire in Gas Turbine Heat Exchangers,” ASME 69-GT-38.

Theoclitus, G., “Heat Exchanger Fires and the Ignition of Solid Metals,” Journal of Engineering for GasTurbines and Power, Vol. 107, July 1985, pp. 607–612.

K.3 References for Extracts in Informational Sections.

NFPA 69, Standard on Explosion Prevention Systems, 2014 edition. .




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Committee Statement

CommitteeStatement:

The committee will review the referenced documents at the second draft meeting so that theywill have a more timely picture of what has been updated since the last edition was issued.

ResponseMessage:

Public Input No. 242-NFPA 85-2017 [Section No. K.1.2.5]


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technical committee on heat recovery steam generators … · purging of hrsg/bypass stack. steve...

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