hazloc seminar- 4 hr boxborough - intertek · 2014-01-16 · – if compliant, a ‘listing report...

Hazardous LocationsA look at Hazardous Locations Product Certification

Presented By

Jeremy Neagle

Assistant Chief Engineer

Hazardous Locations Products

Cortland, NY

Intertek Boxborough, MA 10 November 2009

Objectives of this presentation

This presentation is an overview of Hazardous Locations product certification. By the end of this presentation you should be able to understand the following:

• Part 1 – Intertek Overview• Part 2 – How to minimize time and cost of a certification project • Part 3 – Explosion Safety History• Part 4 – Hazardous Locations Overview• Part 5 – North America• Part 6 – ATEX• Part 7 – IECEx• Part 8 – Equipment Protection Levels (EPL’s)• Part 9 – Explosionproof/Flameproof• Part 10 – Intrinsic Safety• Part 11 –Closing/Q&A

PART 1Intertek Group PLC

Overview

A pioneering history spanning more than a 100 years

• 1885: Caleb Brett founds a marine surveying business

• 1888 Milton Hersey founds what later becomes Warnock-Hersey

• 1896: Thomas Edison establishes what’s later renamed as Electrical Testing Laboratories (ETL)

• Today : Now recognised by the “ETL” mark

Our heritage

An extensive global network

– Labs/Offices > 1,000– People > 23,000– Countries > 100

• Competitive know-how for our customers in diverse markets

• FTSE 100• Market capitalisation at £1.5bn

By The Numbers…

> Billions of products globally feature our certification marks

> More than 2,000,000 annual tests, inspections, certifications

> Market access to nearly all 195 countries on 6 of 7 continents

> 89 Product Safety, Performance and EMC laboratories, globally

> More proprietary certification products than any other certifier – from ETL & Energy Efficiency to Quality/Performance & RoHS

> 2nd largest certification organization in North America

Conversions from £ to $ at 2008 constant exchange rates

7

Electrical & Electronic

• Product safety

• Electromagnetic compatibility• Product performance

• Energy efficiency

• Global approvals: providing access to more than 120 countries

ServicesIntertek offers the fastest and most responsive testing and certification services in:-

CustomersPanasonic, BRK First Alert, Honeywell

Energy & Fuels

• Specialist exploration & production technical services

• Inspection of crude oil and refined cargoes

• Metering, measurement, calibration & fiscal allocation• Testing and certification of petroleum, refined products & natural gas

• Catalyst & process technical services

• Renewable energy support services from bio-fuels testing to wind turbine inspection

• Manpower support and laboratory outsourcing services

CustomersBP, Shell, ExxonMobil, Saudi Aramco, Chevron Texaco, Valero

ServicesHelping energy companies improve efficiency along the entire supply chain: from oil exploration through to transport, refining, trading & marketing. Services include:

• Speed and responsiveness –appreciating the importance of “time-to-market”

• In-depth industry understanding• We offer one global, consistent

service tailored to meet local business needs

Service excellence

• OSHA accredited Nationally Recognized Testing Laboratory (NRTL) for Listing in the U.S.

• Standards Council of Canada accredited Certification Organization (CO) and Testing Organization (TO) for Listing in Canada

• UKAS Accredited Notified Body for the ATEX Directive (94/9/EC)

• IECEx Certification Body (CB) and Test Laboratory (TL)• Full Hazloc Training provider, including an Accredited

COMPEX Training Center• Site Safety Services provider (Risk Assessment, Area

Classification and Inspection)• Specialist in Oil Tools, Rigs and Skids

Intertek’s Hazardous Location Credentials

Global Accreditations/ApprovalsAMERICAS� USA : OSHA� USA : NVLAP� USA : FCC� USA : A2LA� Canada : IC� Argentina : IRAM� Mexico : NOM

EUROPE

� EU : ATEX Notified Body

� Sweden : SWEDAC

� Germany : ZLS

� UK : UKAS

� UK : VCA

� UK : BEAB

� Poland : PCBC

� Russia : ROSTEST

� Israel : SII

� Belarus : Bellis

� Serbia : Kvalitet

ASIA PACIFIC

� Australia : ESO

� China : CNAL

� Hong Kong : HKAS

� Japan : METI

� Japan : JET

� Japan : VCCI

� Korea : KETI

� Singapore : Spring

� Taiwan : BSMI

� Thailand : TISI

� South Africa : SABS

� Saudi Arabia : KSA

� Kuwait : KUCAS

� Nigeria : SONCAP

AFRICA & MIDDLE EAST

Hazardous Location Technical Services

• Product Certification– US/CAN – cETLus Listing– ATEX – EU and other adoptive regions (Middle East, etc.)– IECEx – Members Countries of the International IECEx

Scheme• Field Evaluations/Special Inspections• Site Services

– Consultancy– Inspections and Risk Assessments (Assemblies or Plant)– Audits & Certification

• Training– Open session– Tailored

Listing, Recognition, & Classification

• Listing– Evaluation & Performance Tests are Conducted– If Compliant, a ‘Listing Report’ is Generated– The NRTL Approves the Manufacturer to Apply a Listing

Mark (e.g., ETL)– Surveillance Services Conducted

• Typically Every 90 Days• Unannounced Visits• Ensures Compliance to the Listing Report

Depending on circumstances, Intertek may issue a Listing, Recognition, or Classification for a given product.


• Recognition– Component level certification of products or sub-

assemblies incomplete in construction features, or restricted in performance

– Use of a recognized component necessitates evaluation of the component’s ‘Conditions of Acceptability’ in the end product

– Not suitable for field installation



• Classifications– ‘Classified’ products do not comply with all aspects of a

standard (e.g., empty explosionproof enclosures)– Apply to specifics hazards/risks (e.g. safety vs.

performance)– Essential to read limitations found on labeling/documents


Field Evaluation/Special Inspection

• Field Evaluations or Special Inspections may be performed for certain types of products to determine general safety.

• ‘Sound Engineering Judgment’ can be utilized in determining compliance– Risks of Shock, Fire, Mechanical Hazards are Evaluated

– Construction Evaluation & Limited Performance Tests

• In the US these are referred to as Field Evaluations or Field Labels, in Canada the term Special Inspection applies.

• While US Hazloc Field Evaluations may be performed, Canadian regulations prohibit Special Inspection of Hazardous Location equipment.

Limited Production Certification

An alternative to Listing is the Limited Production Certification (LPC)

• LPC is a method of certifying ‘one of a kind’ products or products of very low production

• Typically best suited for a limited run of production in a maximum 3-month period

• Product is evaluated for compliance with the appropriate standard

• No formal surveillance services• Compliant product is marked with the ETL label

PART 2How to minimize the time and cost

of a certification project

Canadian Electrical Code

18-056 Non-essential electrical equipment(1) No electrical equipment shall be used in a hazardous location, unless the equipment is essential to the processes being carried on therein.(2) Service equipment, panelboards, switchboards, and similar electrical equipment shall, where practicable, be located in rooms or sections of the building in which hazardous conditions do not exist.

Designing for Hazardous Locations

• What Market?– Canada, US, ATEX…etc

• What Classification?– Class I, II, III Division 1, 2– Zone 0, 1, 2

• What Protection Technique?– How have you designed the product

• What Environmental conditions?– Indoor or Outdoor Use (NEMA or Type rating)– IP– Extended ambient temperature range

• ATEX or IECEx?– Do you operate a Registered Quality System (ISO 9001)

Preliminary design review

• A Preliminary Design Review is a brief review of the critical areas of a products design intended to identify major non-compliances.

• Preliminary Design Reviews can minimize certification time and cost.

• In most cases the cost of the PDR can be credited against the complete evaluation project.

Product Certification Flowchart

How to prepare a checklist to successfully test and certify a product

• Schematic/wiring diagrams• P&ID• BOM/Critical component list• Product manuals/literature• Certification details (environmental conditions,

temperature ranges, Hazloc rating)• Product and component samples as necessary• Description of how product was designed to comply

Drawings and Documentation

All drawings and documentation should be official documents under a document control program. Specifically, each document should contain:

– A title block showing the manufacturer’s name– Unique drawing number– Revision level

Draft or unreleased drawings may be used for initial evaluation, but officially released drawings are necessary for completion of certification reports.

Drawings and Documentation

Typical drawings include:– Block diagrams– Control/Installation drawings

• Intrinsic Safety Control drawings should be in accordance with ISA RP12.02.02– Instruction/Operation/Maintenance manuals– Electrical schematics– Wiring diagrams– Printed Circuit Board component layout and trace artwork

• Showing trace routing, plating thickness, PCB thickness, ‘stack-up’, minimum track width

• Scaled artwork or Gerber files may be provided– Assembly/Sub-assembly drawings– Bill of materials showing component details

• Including component manufacturer’s name, model number, ratings, and approval status

– Marking drawings• Including marking method and location

– Casting/Machining drawings• Including critical physical dimensions with tolerances, wall thickness, thread

specifications with gauging/tolerance

Typical problems that arise during the certification process

• General lack of understanding of the certification process or standards

• Slow response to identified non-compliances• Incomplete/incorrect drawings or documentation• Incomplete/incorrect Markings (including French

Caution and Warning Text)• Incomplete/inadequate product or component

samples

How to avoid costly delays

• Identify all product variations up front• Conduct a PDR to identify major issues and get on

the same page with the evaluating engineer• Set up drawings and documentation such that only

critical aspects are controlled• Complete Certification Agreements/FUS paperwork

prior to completion of product evaluation• Commit to a schedule as soon as possible

Aspects of equipment design which affect compliance

• Use of components outside of their ratings (e.g., ambient temperature)

• IS/NI systems, incorrect assumption of ‘simple apparatus’, non-certified I.S. apparatus, control drawing details

• Wiring methods, conduit/cable seals, etc.• Incorrect holes, threading/gauging or modifications

to X.P. enclosures• Energized equipment prior to purge cycle• Flammable process fluid seals

Use of non-certified components

• US/Canadian components• ATEX components• Non-certified components

Some components of simple design may be evaluated for use in the product, but often the necessary technical details can’t be obtained.

In most cases it is more cost effective to replace the component with a Listed version.

PART 3Explosion Safety: A Brief History

In 1913, a methane explosion at Universal Colliery, in Senghenydd, South Wales, killed over 400 miners.

• The subsequent investigation found that the signalling system, consisting of a pair of bare wires connected to a bell at the surface, was capable of igniting a flammable mixture of methane and air.

• The explosion safety industry was born, followed by a long evolutionary process in the safety of workers in potentially explosive atmospheres.

• Subsequent research in Germany, UK, US and around the world lead to the development of many of the Hazardous Location protection techniques used today.

Affected IndustriesWhere might you find a Hazardous Location?

• Any industry that processes, uses or manufactures materials thatmay give rise to a flammable atmosphere (gas, mist, liquid, dusts or even small fibers) may have a Hazardous Location. Such industries/processes include:

– Oil and Gas Drilling– Petrochemical Refining and Processing– Fuel Storage– Chemical manufacturing– Car Manufacturing– Water Treatment– Power Generation– Pharmaceutical– Distilleries– Food manufacturers– Aviation– Military– Painting

PART 4Hazardous Location Overview

What is an explosion?What is an explosion?

An explosion is any An explosion is any uncontrolled combustion uncontrolled combustion

wave.wave.

Explosion Properties

In order to create an explosion there has to be fuel (for example an explosive gas such as hydrogen or methane), an oxidizer (such as the oxygen in air) and a source of ignition energy (for example, a hot surface or an electrical spark).

These three items are commonly referred to as ‘the fire triangle’


Where fuel and oxygen (normally the oxygen in air) are present in the

workplace, potential ignition sources must be rendered safe to an acceptable

level for the risk.

– At a critical concentration called the most easily ignitable concentration (MEIC), the amount of energy required to cause ignition is minimal.

– The critical energy at the MEIC is called minimum ignition energy (MIE).


Gas, Vapor and MistGas, Vapor and Mist

Most flammable gasses, vapors and mists must be mixed with oxygen to make them burn. There is about 20-21% oxygen in the air we breath. Mixtures of a flammable gas and certain percentages of air will burn if ignited.

Too much or too little oxygen, the mixture will not ignite. The upper and lower concentrations of gas in atmospheric air, by volume, are known as their explosive or flammability limits.

Lower Explosive Limit (LEL)The concentration of flammable gas or vapor in air, below which the gas atmosphere is not explosive.

Upper Explosive Limit (UEL)The concentration of flammable gas or vapor in air, above which the gas atmosphere is not explosive.


Examples of Explosive Limits

75.64Hydrogen

1003Acetylene

342.7Ethylene

9.52Propane

155Methane

UEL (%) LEL (%) Substance

Gas Groups (IEC Method)The gases are divided into two groups:

Group I for mines susceptible to methane (firedamp).

Group II for explosive gases for locations other than mines; group II isfurther divided into three sub-divisions (groups):

Explosive Atmosphere

IIA, for atmospheres containing Propane or gases of an equivalent hazard.

IIB, for atmospheres containing Ethylene or gases of an equivalent hazard.

IIC, for atmospheres containing Hydrogen, Acetylene or gases of an equivalent hazard.


Gas Groups (NA Method)The gases are divided into four groups:

A, for atmospheres containing Acetylene or gases of an equivalenthazard.

B, for atmospheres containing Hydrogen or gases of an equivalent hazard.

C, for atmospheres containing Ethylene or gases of an equivalent hazard.

D, for atmospheres containing Propane or gases of an equivalent hazard.


The auto-ignition temperature is the temperature, in °C, at which a gas will ignite spontaneously without another source of ignition.

Because these temperatures do not correspond with the gas groupings, a temperature code was established.

Temperature Class

The resulting temperature codes for the substances listed previously (temperature classification) are shown below:

T1Hydrogen

T2 Acetylene

T2 Ethylene

T1Propane

T1Methane

Temp ClassSubstance

Temperature Class

Temperature ClassThe full list of temperature codes are

85T6

100T5

135T4

200T3

300T2

450T1

Max Temp limit (°°°°C)

Temperature Class

Effects of Oxygen Enrichment, Temperature, and Pressure

Variations in oxygen content, initial temperature and initial pressure can have a significant impact on ignition sensitivity and the severity of an explosion.


Oxygen Enrichment

Oxygen enrichment increases the heat release within the combustion zone of the developing flame-front and therefore decreases the required initial energy contribution from the ignition source.


Oxygen Enrichment

• The most easily ignited concentration of oxygen and vapors or gases ignites at about one hundredth of the minimum ignition energy of the most easily ignited concentration of the same vapor or gas in air.

• Because the flame speeds are considerably higher, the pressure rise will also be much higher.


Oxygen Enrichment

No means of explosion protection considered safe for atmospheric mixtures should be considered safe in oxygen enriched mixtures without careful examination.


Temperature

The qualitative effect of increasing temperature is relatively easy to estimate. Every material has an auto-ignition temperature, AIT (or SIT, spontaneous ignition temperature) at which it will ignite without the introduction of an external ignition source. Obviously, as the temperature of a mixture is raised, the amount of additional energy required for ignition will decrease, reaching zero at the AIT.


Pressure

The effect of pressure is understandable if one considers that when pressure increases the number of molecules per unit volume increases (i.e., the density of the mixture increases). The heat release per unit volume will consequently increase, and the ignition energy required to cause the incipient flame sphere to grow to its critical diameter decreases.


Pressure

Similarly, decreasing pressure decreases the amount of energy released in the combustion zone and increases the required electrical ignition energy.

This relationship has been verified experimentally over many atmospheres of pressure change.

Doubling the pressure of a gas cuts the ignition energy to approximately 25% of its former value.


Dusts

Around 50 explosions are reported per year, ranging from small deflagrations to building destroying detonations which lead to large numbers of fatalities. They are usually associated with the grain and mining industries, however they can occur whenever a process uses particulate materials, either as feed stocks, intermediates or products.

There are a few basic rules to observe to see wheth er a dust is capable of causing a dust explosion:

�The dust must be combustible.

�The dust must be capable of becoming airborne.

�The dust concentration must be within the explosive range.

�An ignition source must be present.

�The atmosphere must contain sufficient oxygen to support and sustain combustion.

Explosive Concentrations

Dust cloud explosions can only occur if the dust concentration is within certain limits.

This is analogous with the concept of upper and lower flammable limits of mixtures of gas (or vapors) and air.

In general the lowest concentration of dust that can give a dustexplosion is around 50-100g/m3 and the maximum is 2-3kg/m3 .

These limits are dependent on the particular chemical in question and on the particle size distribution; however they are included here to give an idea of the orders of magnitude involved.

Primary and Secondary Explosions

The concentrations needed for a dust explosion are rarely seen outside of process vessels, hence most severe dust explosions start within a piece of equipment (such as mills, mixers, screens, dryers, cyclones, hoppers, filters, bucket elevators, silos, aspirati on ducts, andpneumatic transit systems). Explosions in these areas are known as Primary Explosions.

Secondary explosions occur when dust, which has accumulated in other areas (such as above ceilings or on roof trusses), is thrown into suspension by the primary explosion and then ignited.

60170610Coal

80410520Cellulose

80460580Cocoa Power

80300510Grain

100300510Tea

80300470Flour

Ignition Energy

mJ

Ignition TempDeg C (layer)

Ignition TempDeg C (cloud)

Dust

Dust Properties that affect the Dust Explosion Hazar d

Ignition HazardsIf after conducting a risk analysis and area classification a potentially explosive atmosphere is found to exist, efforts shall be made to remove all sources of ignition from the hazardous area.

If this is not possible, protective measures shall be implemented.

Hot Surfaces

If an explosive atmosphere comes into contact with a heated surface, ignition can occur.

The capability of a heated surface to cause ignition depends on the type and concentration of the particular substance in the mixture with air.

This capability becomes greater with increasing temperature and increasing surface areaIgnition also depends on the size and shape of the heated body.

Flames

Flames, even very small ones, are among the most effective sources of ignition.

No open flames are permitted in Zone 0 and gases from flames and other heated gases are not permissible unless special preventive measures are taken

In other Zones devices with flames are only permissible if the flames are safely enclosed and the temperatures generated are not ignition capable for the area of use.

Mechanically generated sparks

As a result of friction, impact or abrasion processes (such as grinding), particles can become separated from solid materials and become hot due to the energy used in the separation process.

Friction, even between similar ferrous metals and between certain ceramics, can generate hot spots and sparks similar to grinding sparks.

Stray electric currents

Stray currents can flow in electrically conductive systems or parts of systems:

- as return currents in power generating systems, especially in the vicinity of electric railways and large welding systems. - as a result of a short-circuit or of a short-circuit to earth due to faults in the electrical installations, or- as a result of magnetic induction (e.g. near electrical installations with high currents or radio frequencies)

Static electricityThe discharge of charged, insulated conductive parts can easily lead to incendive sparks.

Lightning

If lightning strikes in an explosive atmosphere, ignition will always occur. Even in the absence of lightning strikes, thunderstorms can cause high-induced voltages in equipment, protective systems and components.

The affect of lighting strikes outside the hazardous area needs to be considered.

Radio frequency (RF) energy(104 to 10 12Hz)

Electromagnetic waves are emitted by all systems that generate and use radio-frequency electrical energy (radio-frequency systems), e.g. radio transmitters.

All conductive parts located in the radiation field function as receiving aerials. If the field is powerful enough and if the receiving aerial is sufficiently large, these conductive parts can cause ignition in explosive atmospheres.

Optical energy(380nm to 10µm)

Radiation in this spectral range can, especially when focused, become a source of ignition through absorption by explosive atmospheres or solid surfaces.

Sunlight, for example, can trigger an ignition if objects cause convergence of the radiation (e.g. bottles acting as lenses, concentrating reflectors).

Ionizing Radiation

Electrical equipment which generates ionizing radiation is admissible provided that the energy of a radiated pulse or energy flux (power) of continuous radiation is limited to such a low value that it cannot ignite the explosive atmosphere in that the radiation is safely enclosed.

Ultrasonic Radiation

In the use of ultrasonic sound waves, solid or liquid substances absorb a large proportion of the energy emitted by the electro-acoustic transducer. As a result, the substance exposed to ultrasonic radiation warms up so that, in extreme cases, ignition may be induced.

Ultrasonic waves with a frequency of more than 10 MHz are not be permitted, For ultrasonic waves with a frequency up to 10 MHz the power density of the generated acoustic field shall not exceed 1 mW/mm2, unless it is proven for the case in point that ignition is not possible.

Adiabatic compression and shock waves

In the case of adiabatic or nearly adiabatic compression and in shock waves, such high temperatures can occur that explosive atmospheres (and deposited dust) can be ignited.

The temperature increase depends mainly on the pressure ratio, not on the pressure difference.

Adiabatic compression and shock waves (cont.)

Shock waves are generated, for example, during the sudden relief of high-pressure gases into pipelines. In this process the shock waves are propagated into regions of lower pressure faster than the speed of sound.

When they are diffracted or reflected by pipe bends, constrictions, connection flanges, closed valves etc., very high temperatures can occur.

Exothermic reactions, including self ignition of dusts

Exothermic reactions can act as an ignition source when the rate of heat generation exceeds the rate of heat loss to the surroundings.

Electrical equipment

In the case of electrical equipment, electric sparks and hot surfaces can occur as sources of ignition.

Electric sparks can be generated:- when electric circuits are opened and closed;- by loose connections;- by stray currents.

Protection techniques•A variety of protection techniques are available to mitigate the risks posed by potential ignition sources. •The protection technique(s) employed should be should be selected based on their compatibility with the product or process.

EXPLOSIONPROOF/FLAMEPROOF

Standards: UL 1203/IEC 60079-1

Flamepath

INTRINSIC SAFETY – APPARATUS OR SYSTEMStandards: UL 913/IEC 60079-11

PURGED AND PRESSURIZED ENCLOSUREStandards: NFPA 496/ IEC 60079-2

INCREASED SAFETYStandard: IEC 60079-7

OIL IMMERSIONStandard: IEC 60079-6

POWDER/SAND FILLINGStandard: IEC 60079-5

ENCAPSULATIONStandard: IEC 60079-18

Type n Protection (Non-sparking or Non-incendive)

Standards: ISA 12.12.01/IEC 60079-15

Non sparking/arcing partsRestricted breathingSimplified pressurizationEnergy limited apparatus

Sealed or encapsulated deviceEnclosed breakHermetically sealedNon-incendive component

PART 5North American Hazloc

Requirements

Zones vs. DivisionsNEC 500 vs. NEC 505

The NEC® permits facilities to be classified using the Division system or the Zone system.

Problems arise when the two are intermingled. Division equipment may be used in Zone classified locations, but some Zone classified equipment may not be permitted in Division classified areas.

Zones vs. DivisionsCEC 18 vs. CEC J18

The CEC permits existing facilities to be classified using the Division system, while new facilities are to be classified using the Zone system.

Again, problems arise when the two are intermingled. Division equipment may be used in Zone classified locations, but some Zone classified equipment may not be permitted in Division classified areas.

Traditional North American standards vs. 60079-XX series standards

• Both the US and Canada have adopted the IEC 60079 series of standards, but have maintained their traditional standards

• Either set of requirements may be used depending on whether Division or Zone certification is desired.– The US adoptions include many national deviations which

significantly modify the international requirements.– The Canadian adoptions have minimal national deviations

allowing for a nearly harmonized set of requirements. However, the lack of deviations results in mis-alignment with installation codes.

– The editions of the base standards vary between US, Canada, Europe, and IECEx

Traditional North American standards vs. 60079-XX series standards

• There has not been much activity on the CSA C22.2 Hazloc standards in many years, resulting in requirements which have not kept up with current technology.

• There is no permission for ‘equivalency’marking in either set of CSA standards. Most US standards permit ‘equivalency’marking where permitted by the NEC.

• Many of the 60079-XX include a 4 week aging test on enclosure materials (‘e’, ‘n’, ‘p’, and some ‘i’)

PART 6ATEX (94/9/EC)

What is Atex?

ATEX is a set of European Directives relating to Hazardous Area Installations and spells out a set of Essential Health & Safety Requirements (EHSR’s)

ATEX 95/100a (94/9/EC) - EquipmentATEX 137 (1999/92/EC) - Installations

Why was ATEX introduced ?

To ensure that manufacturers adhere strictly to the latest European Normatives (EN Standards) with respect to design construction & certification.

When Did the ATEX Directive Go Into Effect ?

The ATEX Directive took effect on a voluntary basis on March 1, 1996.Effective July 1, 2003, all products placed on the market or put into service in the EU for use in potentially explosive atmospheres must comply with the ATEX directive

• The CE Marking is a legal requirement for products covered by one or more of the EU directives stipulating its use.

• CE is a TRADE issue, not a safety issue.

Conformity European

ATEX

• Within the Community, the free movement of electrical equipment follows when equipment complies with certain safety requirements recognized in all Member States

• The compliance of electrical equipment may be presumed from the affixing or issue of marks or certificates

When does CE apply?

• Equipment may be placed on the market only if, having been constructed in accordance with good engineering practice in safety matters in force in the Community, it does not endanger the safety of persons, domestic animals or property when properly installed and maintained and used in applications for which it was made

What does CE imply?

The Main CE Directives

• LVD (2006/95/EC)• EMC (2004/108/EC)• Machinery (2006/42/EC)• PED (97/23/EC)• ATEX (94/9/EC)

• Before being placed on the market, equipment must have affixed to it the CE marking attesting to its conformity to the provisions of this Directive, including the conformity assessment procedures

• Where equipment is subject to other Directives concerning other aspects which also provide for the affixing of the CE marking, the latter shall indicate that the equipment in question is also presumed to conform to the provisions of those other Directives

CE Requirements - ATEX

• Compliance with the Essential Health and Safety Requirements of each Directive must be demonstrated.

• Harmonized standards may be used to show presumption of conformity to some of these EHSR’s.

CE Requirements, cont.

ATEX Equipment Types

•Equipment•Protective Systems (Flame Arrestors etc.)•Safety Devices (Intrinsic Safety Barriers etc.)•Components

Equipment Categories

The ATEX Directive, in Annex I, defines five categories of equipment:

M1 and M2 (mining use)CAT 1, CAT 2 , and CAT 3(non-mining use)

The categories relate to the likelihood of the presence of an explosive atmosphere. The classification of equipment into categories enables precautions to be taken that are appropriate for the risk.

Zone 2, 22Cat 3

Zone 1, 21Cat 2, M2

Zone 0, 20Cat 1, M1

AreaEquipment

ATEX 94/9/EC Certification

•Categories 1 and 2 (M1 and M2)– Certification of equipment by Notified Body– Certification of Quality System by Notified Body

•Category 3 – Self Declaration by manufacturer

– Internal Control of Production

Addresses Electrical and Non Electrical Ignition Sources

Equipment that needs ATEX

Product Certification- Electrical

• CAT 1 & 2 Requires a Notified Body & Quality audit• CAT 3 Can be self declared

Product Certification- Non-Electrical

• CAT 1 Requires a Notified Body & Quality audit• CAT 2 Requires a Technical Dossier to be lodged

with a Notified Body• CAT 3 Can be self declared

It is Mandatory for a Quality Assurance Notification (QAN) Certificate to be issued for CAT 1 and CAT 2 electrical equipment and CAT 1 non-electrical equipment.

The Notified Body responsible for the QAN can be identified by a 4 digit number under or adjacent to the CE Mark

Quality System Requirements

Example of ATEX Marking Requirements

ABC Analytical Ltd

Any Street, Birmingham. UK

K 0359II 2 GD

Model 246 controller

Serial No. 12345/03

Ex nA IIC T6ITS09ATEX45678X

Do not open when energized or when a flammable atmosphere is present.

T = 65OC

PART 7IECEx Scheme

IECEx Scheme

• Multilateral Certification Scheme used to obtain National Certification in participating member countries.– Ex Equipment Certification– Ex Personnel Certification

– Ex Service Facility Certification

IECEx Scheme

• Member countries:

IECEx Scheme - Equipment

• Requires:– Evaluation and Testing by IECEx TL to IEC

standards. IECEx TL issues an IECEx Test Report (TR).

– IECEx CB conducts an audit of the Quality Management System of the manufacturer. IECEx CB issues a Quality Assessment Report (QAR).

– TR is endorsed by CB and is used in conjunction with the QAR to create IECEx Certificate of Conformity (CoC).

IECEx Scheme

• Challenges:– IECEx CoC is not solely accepted for

National Certification by many member countries.

– Most member countries have extensive national deviations to the base IEC standards (including using different editions of the base standard).

– Limited availability of IECEx certified components.

PART 8Equipment Protection Levels

(EPL’s)

Equipment protection levels

• Historically, there has been a hard link between Zones or Divisions and permitted equipment protection techniques (e.g., the use of explosionproof equipment in Division 1 locations or intrinsic safety in Zone 0 locations).

• EPL’s are part of an alternative risk assessment method for hazardous location equipment selection.


• The basic principle of the risk assessment approach to equipment selection is that the risk associated with some processes may warrant a higher level of protection than traditionally required.

• Conversely, the consequences associated with explosion of some processes may warrant lower levels of protection than traditionally required.


EPL MaEquipment for installation in a mine susceptible to firedamp, having a "very high" level of protection, which has sufficient security that it is unlikely to become an ignition source in normal operation, during expected malfunctions or during rare malfunctions, even when left energized in the presence of an outbreak of gas.EPL MbEquipment for installation in a mine susceptible to firedamp, having a "high" level of protection, which has sufficient security that it is unlikely to become a source of ignition in normal operation or during expected malfunctions in the time span between there being an outbreak of gas and the equipment being de-energized.


EPL GaEquipment for explosive gas atmospheres, having a "very high" level of protection, which is not a source of ignition in normaloperation, during expected malfunctions or during rare malfunctions.EPL GbEquipment for explosive gas atmospheres, having a "high" level of protection, which is not a source of ignition in normal operation or during expected malfunctions.EPL GcEquipment for explosive gas atmospheres, having a "enhanced" level of protection, which is not a source of ignition in normaloperation and which may have some additional protection to ensure that it remains inactive as an ignition source in the case of regular expected occurrences (for example failure of a lamp).


EPL DaEquipment for combustible dust atmospheres, having a "very high" level of protection, which is not a source of ignition in normal operation, during expected malfunctions, or during rare malfunctions.EPL DbEquipment for combustible dust atmospheres, having a "high" level of protection, which is not a source of ignition in normaloperation or during expected malfunctions.EPL DcEquipment for combustible dust atmospheres, having an "enhanced" level of protection, which is not a source of ignition in normal operation and which may have some additional protection to ensure that it remains inactive as an ignition source in the case of regular expected occurrences. for example failure of a lamp).


• Recent IEC based standards incorporate marking requirements for EPL’s; some of these are inherent to the protection technique (e.g., ‘ia’), while some are new markings (e.g., ‘db’, ‘pxb’).

• Proposals have been made to the 2011 NEC® to recognize the alternate EPL marking which may appear on equipment nameplates.

PART 9Explosionproof/Flameproof

Explosionproof/Flameproof enclosures

• While similar in design and function, explosionproof and flameproof enclosures differ in several distinct ways:– Minimum wall thickness for

explosionproof enclosures– Different flamepath length and gap

dimensions.– Different pressure and propagation

testing methods


• Either ‘off the shelf’ certified enclosures or custom built enclosures can be used when designing a product.

• The requirements for enclosure design are well defined in the applicable standards, covering the critical aspects of flamepath design (length and gap).


• ‘Off the shelf’ enclosures are typically Classified or component certified empty enclosures with conditions of use. Restrictions on:– Electro-mechanical devices– Rotating machines or devices likely to cause

turbulence– Cells and batteries– Liquids/pressurized gases– Ambient conditions– Modifications for entries, windows, operators,

etc.


• Custom designed enclosures should be designed using the wall thickness and flamepath dimensions specified in the applicable standards as a baseline. Conformance can only be determined by test.


• With any enclosure design, the following rules of thumb should be followed:– Use of plastics, epoxies, and sealants should be

kept to a minimum– To avoid pressure piling, the enclosure should

be designed to avoid separate volumes– Where separate volumes or enclosures are

necessary, appropriate seals means should be provided to prevent pre-compression during ignition

– Threaded joints should be designed to conform with both the product standards and thread form standards when applicable.

Explosion Testing

PART 10Intrinsic Safety

Intrinsic Safety

• With the 7th Edition of UL 913, the standards for Intrinsic Safety are quickly becoming harmonized around the world.

• IEC 60079-11 forms the basis for most Intrinsic Safety standards.– The latest requirements include those for levels

of protection ‘ia’, ‘ib’, and ‘ic’.– Introduction of relaxed requirements for

separation distances based on enhanced enclosure performance.

Intrinsic Safety

• Evaluation of Intrinsically Safe circuits takes into account a variety of fault conditions, including: – Up to two ‘countable’ faults, and– Any combination of ‘non-countable’ faults

resulting in the worst-case condition.

• Faults considered during evaluation may not seem logical during circuit design.

• Additional Safety Factors may be applied as specified by the standards.

Intrinsic Safety

• The basic principles of Intrinsic Safety include limiting stored energy in such components as capacitors and inductors, and limiting surface temperatures on components through power limitation.

• Stored energy values are compared to ignition curves or tested for compliance.

Intrinsic Safety

• Surface temperatures are typically calculated based on an assumption of maximum power transfer.

• Component assessments are made based on worst-case ratings, tolerance, and any applicable de-rating based on conditions of use.

Intrinsic Safety

• Cells and Batteries are assessed on an individual cell basis for spark ignition and surface temperature.

• Assemblies of cells are assessed as appropriate based on construction.

• Cell voltages for many types of cell chemistries are specified in the standards. Short-circuit currents and internal resistance may be determined by test.

Spark test apparatus

PART 11Closing

Summary

Many of the topics discussed today were covered only briefly.

If you wish to discuss any of these topics further, or if you would like a tailored training session relevant to your specific products please contact us for details.

Questions?

hazloc seminar- 4 hr boxborough - intertek · 2014-01-16 · – if compliant, a ‘listing report...

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