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hyperion
10-12-2018, 04:52 PM
We are working on a site where the site agent will not allow high-pressure OFN strength or leak testing as he claims that we have to prove that the test does not exceed 250bar-litre under the Pressure Systems Safety Regulations 2000.
Anyone able to give further guidance please as we would normally work under the EN378 requirements?

Tycho
10-12-2018, 06:20 PM
Hi Hyperion,

How big is the system? Seems like the PSSR 2000 has a lot of exceptions that allows you to do testing.

http://www.hse.gov.uk/pUbns/priced/l122.pdf

Starts nicely on page 9 with a flow chart, obviously there is no "relevant fluid in the system", so you go to NO and PSSR does not apply:
15318

Then on page 53, under "Pressure systems excepted from all regulations":
15319

Also on page 53

Exception 4
191
A system which is only a pressure system because it is subject to a leak test
is not covered by the Regulations. For example, radiators under leak test would be
exempt. For a definition of ‘leak test’ and other forms of pressure testing, see the
HSE Guidance Note GS4 Safety in pressure testing.

http://www.hse.gov.uk/pubns/gs4.pdf

Other than that I'm not familiar with the direktives in the UK

hyperion
10-12-2018, 07:24 PM
Thanks Tyco,
That is most helpful.

Tycho
10-12-2018, 11:34 PM
Thanks Tyco,
That is most helpful.

Hope it works out for you :) sounds like your client is a dumbass :)

hyperion
11-12-2018, 08:17 AM
Tyco, you have described him exactly. He is trying everything he can to push the contract completion to its limits. Not quite sure what his agenda is!!

Rob White
11-12-2018, 02:51 PM
We are working on a site where the site agent will not allow high-pressure OFN strength or leak testing as he claims that we have to prove that the test does not exceed 250bar-litre under the Pressure Systems Safety Regulations 2000.
Anyone able to give further guidance please as we would normally work under the EN378 requirements?

http://www.hse.gov.uk/pubns/indg178.pdf

That document does not say you can't do the test, it states that a method statement must be produces first
that's all.

See

What types of typical pressurised systems might require a written scheme of examination?


The following pressurised systems are likely to require a written scheme of
examination:
■ a compressed air receiver and the associated pipework, where the product of
the pressure in bars multiplied by the internal capacity in litres of the receiver is
equal to or greater than 250 bar litres;
■ a steam sterilising autoclave and associated pipework and protective devices;
■ a steam boiler and associated pipework and protective devices;
■ a pressure cooker;
■ a gas-loaded hydraulic accumulator;
■ a vapour compression refrigeration system where the installed power exceeds
25 kW;
■ a narrow-gauge steam locomotive;
■ the components of self-contained breathing apparatus sets (excluding the gas
container); and
■ a fixed liquefied petroleum gas (LPG) storage system, supplying fuel for heating
in a workplace.


Rob

.

Rob White
11-12-2018, 02:56 PM
.

See

http://www.hse.gov.uk/pUbns/priced/l122.pdf

Rob

.

RANGER1
13-12-2018, 08:06 AM
For those who may not know, It is also necessary to check all equipment & pipe/fittings for maximum pressure ratings.
You can only pressure test to the lowest rating, unless it can be isolated.
Relief valves if any, also a consideration.

Rob White
13-12-2018, 12:37 PM
For those who may not know, It is also necessary to check all equipment & pipe/fittings for maximum pressure ratings.
You can only pressure test to the lowest rating, unless it can be isolated.
Relief valves if any, also a consideration.

The PRV is a valid point and in some circumstances the strength test is done without them fitted,
plugs are fitted instead and then the pressure is reduced for the gas tightness test.

All a bit of a ball ache but part of the regulations.

Rob

.

RANGER1
13-12-2018, 04:09 PM
Rob,
Sometimes a pressure relief is fitted at higher pressure also to make it idiot proof during test.

hyperion
14-12-2018, 02:04 PM
Thank you for all of your valued comments. We are progressing with the pressure testing as the client has now accepted that provided we place suitable signage to exclude all bar essential personnel, we can continue. Printed 50 relevant signs and they are on display at the site.

Tycho
14-12-2018, 03:04 PM
Thank you for all of your valued comments. We are progressing with the pressure testing as the client has now accepted that provided we place suitable signage to exclude all bar essential personnel, we can continue. Printed 50 relevant signs and they are on display at the site.

Glad that it worked out :)

Don't know the size of your system, but when I do pressure testing of freezing plants on ships I always stop all work on the decks with plant equipment.

It's never popular to shut down work for 3-4 hours when everyone is rushing to meet the deadline, but I'm in charge of the testing and responsible if anything should happen, so they'll have to live with it if they want the system tested :)