Pressure Test

[gassafe]

Type in uk copperboard pressure testing piping systems on google! It's a PDF file

 

[Kimou]

Ok, so I wasn't wrong and there is a real danger. Thanks gas safe. I guess I don't need to call my friend. And maybe my poor old 1000 year old tutor wasn't so wrong in the end.

 

[Keefy]

With all respect I still don't have a clear idea of what you're asking, probably due to certain things you said since the OP:

When I was in college the tutor wouldn't divulge too much about it because of certain reactions between copper and air goes into the realms of explosives and it wouldn't be prudent of him to give too much away.

Basically because air can compress and it takes a lot more air to raise the gauge, if there was a sudden drop then it can explode.

And it was in reference to high pressures and elements within copper.

I'm not really interested in anybody else's nonsense on what they 'think'.

I just hope someone here can verify what I said in a better way than I can. I stand by my tuition and my tutors of days gone.

I don't even know if it's me who's confused or it's you. Don't take any of this as me trying to take the Michael I'm just trying to show you the bits which need more clarification.

Please explain, it's doing my barnet in.

 

[nicro3]

To use compressed air to test hydraulic pipework at 1.5 working pressure is a no no a small pressure ie half a bar is fine.
A lot of companies use compressed air tests all the time to 1.5 working pressure, which would invalidate any warranty on fittings or pipe.

 

[Keefy]

Okay, after re-reading the whole topic several times over I think the question is:

"Is it illegal and dangerous to pressure test domestic pipework with air?"

 

[nicro3]

Okay, after re-reading the whole topic several times over I think the question is:

"Is it illegal and dangerous to pressure test domestic pipework with air?"

Any thing over one bar yes.

 

[tamz]

It is not illegal but it is dangerous and should only be done after a thorough risk assessment and method statement are prepared.

 

[Kimou]

Keefy- you've already established yourself as helpful. I am sorry if I've confused things. All I said in your highlights is; my tutor said you should not dry test with air, he then went on in his charming way of teaching, which made certain issues memorable, why he couldn't elaborate on the entire chemically related issues of why it's dangerous because his knowledge extends into many subjects and he has a responsibility to not discuss potential explosive manufacture with plumbing students for obvious reasons. Perhaps, in hindsight, I shouldn't have mentioned that anecdote. I just thought I'd put a little character in the post.


the 'nonsense' bit was due to someone not giving me a chance and slating me off unfairly. Perhaps I should've just tolerated that, too- I know people have to deal with a lot of stupidness on here at times and cz he doesn't know me, probably wanted to vent a little. I know we can get a little too involved with this site. I just don't come on much anymore. But in fairness, that reply to me could've been a little less harsh.


the last bit was about hoping someone could give me an answer.


i hope your hair's alright now

 

[tamz]

There is no chemical reaction. Copper can be used in compressed air lines.

Testing existing gas pipes using compressed air is different as it could create an explosive gas air mix inside the pipe therefore it would need purged of the gas first.

 

[Kimou]

Nicro- good man...cheers

Tamz- that's one the chaps was waiting to verify... Thanks. So if anything happened, if you didn't follow that procedure would I be correct in saying you could get done for corporate manslaughter?

 

[billybob150811]

you don't have to test with air no one can force you just don't but your desire to prove the rgi wrong does you no credit he is probably talking about gas pipes which he would test with air your thread seems to change then to water which again can be air tested you then move on to oxygen which you cant use because it would create a potential bomb

 

[Kimou]

There is no chemical reaction. Copper can be used in compressed air lines.

Testing existing gas pipes using compressed air is different as it could create an explosive gas air mix inside the pipe therefore it would need purged of the gas first.

Ok, I must've mixed something up then. Maybe he was referring to that and I got lost somewhere and confused the two.

 

[tamz]

There is a very real danger of injury or even god forbid, death in testing with air at higher pressures.
That is why a risk assessment and method statement should be prepared and strictly adhered to including setting up exclusion zones.
If these steps were not taken and documented and something were to happen then yes you would be liable.

 

[nicro3]

I think an easy way to explain why compressed air is dangerous. Get two balloons blow air into one and fill the other with water, stick in a pin in each, one will go bang and the other dribble

 

[Kimou]

Billy bob- the rgi told me about his practise of putting a compressor on to test for leak before he filled with water. My desire is not to prove him wrong, moreover, to educate him. I clearly believed he was unknowingly creating a huge danger for himself and others around. The potential could even be kids living next door. What would you do if you honestly believed someone was putting themselves in a life threatening situation and never realised?
would you consider yourself trying to be a knowitall or genuinely helping that person?

Which is why I'm taking the time and suffering abuse to try and get some advice from people much more informed and experienced than I am.

it does seem that if I never mentioned that he was RGI I doubt I'd have such a hard time. Not all gas installers know everything.

 

[Kimou]

Tamz- Again, thanks. Your input is appreciated. He was talking about 8bar on dry and still insists its ok. Even Gas safe didn't correct him. I only have his say so that they said that, but if its true, then that's worrying.

 

[Kimou]

I think an easy way to explain why compressed air is dangerous. Get two balloons blow air into one and fill the other with water, stick in a pin in each, one will go bang and the other dribble

Very true. Nice analogy.

 

[nicro3]

Afraid to say many companies use this method to test hydraulic pipework both in the domestic and commercial world. 3,4,6 bar is not uncommon with little regard for the safety of those in area of such tests.

 

[Kimou]

Tamz- is there any document that states this. If it is a code of practice surely something is available? I really want to change this guy's way of testing. I'd hate for something bad to happen.

 

[Kimou]

Afraid to say many companies use this method to test hydraulic pipework both in the domestic and commercial world. 3,4,6 bar is not uncommon with little regard for the safety of those in area of such tests.

that's the problem when you don't regulate our industry properly and force companies to cut corners. It's bad times ahead and will probably get worse.

 

[Keefy]

Apologies but I've got to ask something again;

This friend of yours was talking about carrying out an 8-bar pressure test using air on a copper gas carcass inside a domestic dwelling?

 

[Kimou]

Yeah. Not always 8bar but any pressure. In his mind it's not a consideration. 8 was just an example of roughly what he does.

 

[Kimou]

No not gas. Pipes for rads and water runs.

 

[tamz]

Testing at 8 bar could be very dangerous. If anything were to happen it would be his rse in a sling. No one including him, should be nearer than 3m to any pipe under test at 8 bar

Here is an excerpt from a certain book on how to test with air (i've taken some parts not relevant out). The same risks apply to any pipe tho.

PROCEDURES – PNEUMATIC STRENGTH TESTING
A thorough survey of the pipework section, to detect any major integrity defect, shall be carried out before testing, including inspection of certificates, NDT, etc.
Note: This survey may entail checking the accuracy of any plans, any other information provided and the mechanical integrity of installations.

As far as is reasonably practicable, joints should be exposed during the strength test and indications of leakage sought using leak detection fluid (LDF), but only after the pressure has been reduced to MOP for the section.
It shall be ensured that all pipework and components have been designed, installed and anchored to withstand STP.

A risk analysis shall be carried out to confirm that the risk involved is acceptable. If it is not, then hydrostatic testing shall be carried out.

Before testing, the following actions shall be taken:
• ensure all isolation valves are plugged securely or blanked off and the valves are in the open position to ensure the valve body is tested
• where necessary, remove any component that is not to be included in the test (see clause 4.4.1). Install spool pieces or blanks
• ensure there is a means of pressurising the system either with dry compressed air or nitrogen (above freezing point if expanded from bottled nitrogen)
• incorporate (in the connection of the pressurisation medium to the section) suitably adjusted regulators and a full flow safety valve(s) to prevent pressurisation above STP.

An exclusion zone, in accordance with Table 2, shall be set up around the area of any pipework section for which STP exceeds 1 bar. The minimum distance for persons to be from the pipework is based on STP and the volume of the section being tested. Personnel shall not be within this distance of the section while pressurising and during the stabilization and test periods.
Note: In general, this will mean that the pressurisation equipment and test instruments are also outside this area, the latter being piped into the area in small bore pipework. The distances detailed in Table 2 are based on the centre-line of the pipework and extend both sides.

A final inspection of the pipework section shall be carried out to ensure that it is ready for the test (it shall be ensured that any exclusion zone is clear of all personnel - see Table 2).

If STP exceeds 2 bar, a check for general integrity, for example for open ends, shall be carried out at a pressure of 350 mbar.

The pipework section shall be pressurised slowly. If STP exceeds 2 bar then, after reaching 2 bar, the section pressure shall be increased in 10% stages up to STP leaving a short period between each increase in pressure.

Following a satisfactory test the pressure in the pipework section shall be vented and pipework left in a safe condition. Any exclusion zone then can be re-opened for all site personnel.

The strength test shall be documented and included in any site Health and Safety File. Results should be recorded on a formal certificate, a copy of which should be given to the owner/operator of the pipework tested.
STP and MOP shall be recorded clearly and be available for reference by any party subsequently working on the installation.

 

[Keefy]

Aaaaaaaaaaaaaaaaaaarrrrggggghhhhhhh!!!