updating eemua 168 guidance on pressure testing

Engineering Equipment andMaterials Users Association ©

Updating EEMUA 168Guidance on Pressure Testing

Mark CooperConsultant to EEMUA

IMechE Pressure Testing Seminar 2021


Why?

• 20 reasons – fatalities and serious injuries amongst staff and contractors, the people we ask to pressure test our equipment

• Before I describe the new edition of EEMUA 168, I’m going to flip straight the final appendix, here you have over 30 examples of where testing went wrong and the lessons to learn

• This is such a large number of examples, so important, that we are setting it up as a live data base that anyone will be able to access – on the EEMUA website. It will be updated if and when new incidents arise

• Looking at the examples, the conclusions you would draw, and it is no different to what came out of this seminar in December 2017, is that pressure testing can be a high risk activity - the competence of those performing pressure testing needs to improve …

• … to stop another 20 fatalities and injuries

A call went out to industry after the 2017 seminar to form a Working Group to tackle this issue

IMechE Pressure Testing Seminar 2021 2


Incident from Appendix Lesson LearnedHydrostatic test of 80 feet of 24 ins pipeline. The pipeline was to be pressurised to 149 bar. When the test pressure reached 120 bar the weld around the intrados of an elbow split and four workers were hit by a powerful water jet

No exclusion zone for hydrostatic test

During a 100 barg pneumatic test of a furnace coil, a flange fitted for testing blew off, striking a person passing by in the head causing instant death

No exclusion zone, no line-of-sight barrier, poorly designed flange connection

Workshop hydrostatic test of spool piece. The team set up for a test pressure based on the blind flanges rating that had been used for previous spools. After incremental pressure increase, the pressure stopped rising. The Operator went closer to inspect for an issue with hydrotest pump or leak at the flange. At that time, the spool pipe burst and the operator was fatally hit in the face by a blade of water

Failure to follow the test procedure which stated a lower test pressure based on pipe capability. Operator carried out intrusive inspection without reducing the pressure (which was well above safe pressure)

Lessons Learned



Engineering Equipment and Materials UsersAssociation

• The industry WG identified EEMUA as a good platform for new guidance – it already has guidance on pressure testing and managing competence

• Stefan Kukula, EEMUA’s Chief Executive, will talk more about EEMUA next … Relevant to pressure testing, EEMUA has – Suite of guidance documents on managing pressure systems

including EEMUA 177, 193, 223, 231– History of training in Mechanical Integrity – EEMUA 168: Guide to pressure testing of in-service pressurised equipment,

was first issued thirty years ago• EEMUA also has an awareness level, e-learning module, on the new edition of

168 being developed in tandem with the guidance



EEMUA Guidance on Pressure Testing

• The industry WG reviewed the current guidance and said it must extend its scope– The new version now covers the full life cycle – manufacture and

construction, as well as in-service testing– It now addresses competency of those involved– It now has more content on how to perform pressure tests safely

• When will it be available?• It is in its final draft …• … round-table discussions this afternoon are an opportunity for us to make

sure we have taken on board your views



What’s in the box?

Reasons for pressure testing Not always clear! Historical element from the era of boiler explosions and lack of reliable NDT

Types of pressure testing Different terminology used across standards for the same test

Hazards of pressure testing

Sudden release of stored energy from the equipment under test, though many fatalities and serious injuries are from failure of some part of the test rig and its connections, or a small part of the equipment blowing out

Competency Describes new Competency FrameworkSpecial cases Waiving a pressure test – EEMUA 223, closure welds

Undertaking pressure tests safely This an enlarged section where we have built on the presentation Stuart Turner gave to this seminar in 2017

Appendices Includes the current lessons learned list



Reasons to pressure test?

• At the manufacture and construction, or site assembly stage, and after plant modifications / repairs, the pressure test is universally required by standards. It is an important part of the final acceptance test of pressure equipment, usually witnessed by an approval body.

• It tells you there are no leaks – from through wall defects in components, or from joints, flanges, screwed threads, glands. Distortion may also be measured

• If the test pressure is high enough, it may achieve a form of mechanical stress relief or shakedown at high stress points; residual yield level stresses in welds or formed parts may be reduced. Better fatigue performance may result

• However, it doesn’t quantify the integrity of the equipment nor the quality of its construction …

• In-service testing is frequently undertaken to confirm there are no leaks at joints, though it may also be required to re-qualify equipment



Types of test?• Unfortunately, there is no standardisation in test terminology (nor test

pressures) between standards. 168 uses the following terms:– For the acceptance test - Standard Pressure Test

• Typically performed at 1.1 – 1.5 times the design pressure and for systems operating above ambient can include an uplift to account for material strength

• Also referred to as Proof Test (though this means something different in other references), Pressure Test, Standard Test and Leak Test.

• For a leak test – Tightness Test• Typically performed up to operating pressure. Service Tightness Test uses the service fluid. Sensitive

Tightness Test performed at lower pressure

• Consider any form of first pressurisation or re-pressurisation after a significant period out of service, plant maintenance, repair or modification is a pressure test – recognise this and make sure you carry out risk assessment to determine what precautions you need to take



Hazards

• Component ejection (failure of threads, welds, bolts)• Connector failure, hose whip, pipe whip• Fracture of vessel, weld split, branch/head, flange, jets, reaction forces

• Release of Stored energy Hydrostatic Pneumatic

1 m dia x 3 m long100 barg test pressure

0.06 MJ (14 g TNT) 43 MJ (10 kg TNT)(0.4 barg, 6 psi)

• Brittle Fracture - blast wave / missiles PCC-2 55/80 m exclusion zone

P P



Section 5 Competency

Simple, everyday, Standard Hydrostatic Pressure Test of a

pipe spool on a workshop bench using a handpump

Periodical Pneumatic Tightness Test of a large interconnected pipework system out on site

Standard Hydrostatic Pressure Test of large multi-chambered,

multi-nozzle pressure vessel at a manufacturers

Standard Pneumatic Pressure Test of a small, cylindrical

pressure vessel at a manufacturers

Common Competence Framework?

Our aim was to devise a model framework that users could adapt to the requirements of their pressure testing – to reflect the range and complexity of equipment and testing, the level of potential risks and the environment they operate in (e.g. discretion, judgement and decision making and extent of supervision), etc.

Scope excludes tanks (refer to EEMUA 159) and routine testing of components using dedicated, certified equipment designed to manage the risks (e.g. transportable pressure equipment)



Test Operatives

Simple, commonly found model throughout roles in industry

Operator Pressure Test Operator Level 1Supervisor Pressure Test Supervisor Level 2Expert Pressure Test Expert Level 3

For low risk, well defined, testing, the Level 2 and 3 may be fulfilled by the same roleLevel 3 may not be expert in all aspects but can access specialists, materials engineers, corrosion engineers, structural engineers, etc. as required - Level 3 may not necessarily be in the company



Organisational Positions

PT Level PT Title Example Organisational Position

1 Pressure Test Operator Inspector, Technician, Operator

2 Pressure Test Supervisor

Area Inspector, group leader, Pressure Test Facility Manager / Laboratory Manager, Construction Manager

3 Pressure Test Expert Senior Manager / Technical Manager

Technical Leadership role – designated company Technical Authority, Subject Matter Expert

The guidance gives typical levels of engineering training, qualifications and experience for each role. Reference can be made to UKAS RG2 Appendix 1 and Table 1, and categories of pressure systems described in the ACOP to the Pressure Systems Safety Regulations, L122



Roles and responsibilities need defining

PT Level Extract from Typical Duties and Responsibilities

1

. . . . . . . . . . . . . . . . Establish barriers and exclusion zones, in accordance with procedures and

risk assessments Review equipment under test (size, supporting, stability, etc.), prepare and

check joints, establish safe test gauge positions, drains and vents, check ratings and condition of temporary connections and hoses, tether checks, review risk assessment

. . . . . . . . Perform the pressure test in accordance with an approved pressure testing

procedure and risk assessment . . . . . . . .




2

. . . . . . . . Draw up test procedures Draw up a risk assessment for the pressure test based on local conditions at

the test facility (submit to the Level 3, as necessary) . . . . . . . . Supervise the performance of the pressure test by the Level 1 . . . . . . . . . . . . . . . . Control movement of third parties witnessing tests (e.g. Notified Bodies,

Approved Bodies, PSSR Competent Persons, Integrity Assessors) . . . . . . . .





3

. . . . . . . . Be accountable for the safe performance of pressure testing for the facility/ies

under their jurisdiction . . . . . . . . Draw up procedures for complex (and higher risk) pressure testing Engage the expertise of specialists in corrosion, materials, fitness for purpose

assessments, etc., as required in drawing up procedures Interact with external stakeholders (e.g. Notified Bodies, Approved Bodies,

Inspection Bodies, PSSR Competent Person) . . . . . . . . Draw up appropriate input to training providers and company QMS processes

for qualification and ongoing assurance of qualified levels 1 and 2 . . . . . . . .




Knowledge and Understanding

• Competence – the ability to apply the necessary practical and theoretical knowledge, skills and personal attributes for testing to be carried out safely

• 168 follows the approach in ASME PCC-1 (Appendix A – Training and Qualification of Bolted Joint Assembly Personnel) and EN 1591-4 (Qualification of personnel competency in the assembly of the bolted connections of critical service pressurised systems). Bolted joint assembly is a very important aspect of leak free performance -Gary Milne will talk about this later

– In the new guidance we have defined a list of fundamental, or core topics, of knowledge and practical understanding considered relevant for competency in pressure testing

– They are listed under four headings: Operating Environment; Organisational Arrangements; Plant and Equipment; and Continuous Improvement



Fundamental Knowledge Extract

PTC3 Plant and Equipment Sub-topic Examples PTLevel 1

PTLevel 2

PTC3.1 Isolation from the SystemSecure isolation, PTW, safe isolation of test equipment

K E

PTC3.2 Temporary plugs and blindsIntegrity of fixings, positions and potential projectile directions and distances

E E

PTC3.3 Component ratings . . . . . . . . K E

PTC3.4 Test rig specification

Max flow rate from rig, volume under test, holding down clamps, calibration and certification, safety features, exhaust ports, maximum pressure limits

E E

PTC3.5 Test rig control . . . . . . . . E E

PTC3.9 Flanges, gaskets, bolting, tightening

Flange assembly, faces and gaskets, bolting specifications, tightening procedures

K E



Competence

• Over 30 topics of fundamental knowledge are described, each with sub-topic examples

• These effectively form the basis for assessing individuals’ knowledge and understanding (and provide a syllabus for training)

• However, as we noted earlier, there is a wide variability in testing complexity and associated risk in different circumstances – one-size-fits-all doesn’t work

• The extent of knowledge and depth of understanding required for a particular role in an organisation depends on the complexity and potential risk and how the responsibilities are defined

• Further steps to take are to decide which of the fundamental topics apply and what depth of knowledge and understanding each role requires



Depth of Knowledge Example

PTC3 Plant and Equipment Sub-topic Examples PTLevel 1

PTLevel 2

PTC3.1 Isolation from the SystemSecure isolation, PTW, safe isolation of test equipment

K E

PTC3.2 Temporary plugs and blindsIntegrity of fixings, positions and potential projectile directions and distances

E E

PTC3.3 Component ratings . . . . . . . .

PTC3.4 Test rig specification

Max flow rate from rig, volume under test, holding down clamps, calibration and certification, safety features, exhaust ports, maximum pressure limits

A K

PTC3.5 Test rig control . . . . . . . .

PTC3.9 Flanges, gaskets, bolting, tightening

. . . . . . . . A AwareK KnowledgeableE Extensive



Steps in Applying Model Framework

• Identify roles

• Define duties and responsibilities

• Decide qualifications and experience to match complexity and potential risk

• Decide relevant fundamental topics/sub-topics to match complexity and risk

• Determine depth of knowledge and understanding against fundamentals

• Assess job holders, train as required, certify competence

Stefan is going to talk next about options for training and certification



Section 7: Undertaking

Pressure Tests Safely

Processes People Equipment

Lack of or poor policy Unclear competency

requirements Joint management

procedures, unclear roles and responsibilities

Poor risk assessment and procedures

Lack of consideration of material properties and in-service degradation, test temperature to prevent brittle fracture

Failure to consider addition risks of testing, e.g.. weight of water, equipment stability, proper anchoring (accounting for failure)

Unsafe positioning of test rig Exclusion zone requirements

not defined

Unconscious incompetence Lack of training and

understanding of stored energy

Roles and responsibilities not clear

Failure to follow rules Failure to enforce rules, e.g.

exclusion zones Lack of planning Pressure to complete Safety and learning culture Lack of awareness of

procedures Uncontrolled intrusive

examination

Lack of maintenance Incorrect settings / ratings Corroded / degraded

equipment Worn fixings through

repeated use, lack of full thread engagement

Inadequate margin on flexible hose ratings

Over-rated test rig (e.g. unnecessary flow capacity and pressure capability)

Lack of overpressure protection, incorrectly set, not calibrated or certified

Flow capacity protective devices below that of rig flow capacity

Inadequate pressure control and siting

Lack of tethering

What can put people and equipment at risk during pressure tests?



Undertaking Pressure Tests Safely

POLICY

PLANNING

PREPARATION

EXECUTION

COMPLETION

Section 7 is structured under these headingsThe content is based on the presentation that Stuart Turner gave to this seminar in 2017



Undertaking Pressure Tests Safely

Whilst standards will generally drive the type of testing required, the new guidance contains charts to aid with considerations for pressure type selection for new and in-service equipment Section 7 of the new guidance provides extensive information on considerations

when selecting a pressure test type and on performing the tests



Updating EEMUA 168Guidance on Pressure Testing

Mark CooperConsultant to EEMUA

Thank you for listening

IMechE Pressure Testing Seminar 2021

updating eemua 168 guidance on pressure testing

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