Hose testing...WTF

[Fireman]

We're having a big company discussion atm about the hydrant hose testing methods we're using on board. Seems to be a few tried and trusted engineers are saying testing the fire hose with pressurized air is dangerous. The way it's being explained is the pressurized air (Although less than 5bar), will expand rapidly inside a hose compared to water. The captain wants us to submit something to the DPA, so thought I'd get a few second opinions.

I've been on three ships now, with two companies. 2/3 have been testing with water, whilst the other one, a ro-ro with something close to 250 hoses onboard is insisting on using air, against a relatively new 3/0 who, as far as I can see is doing it properly with water... the only problem being, that as a cadet, it just so happens to be your sole responsibility to lug the bloody things to the upper deck - rather than testing with air on the floor they came from!

thanks for any bright Ideas/thoughts

fireman

[size4riggerboots]

I'd have to go and read the back part of the FFA code, where they detail all the requirements for testing all this stuff. However, how is one supposed to be able to spot a leak when doing it with air???

I know lugging them about is a ball ache, but it's "character building" (I know, I know, I hate people who say that to me, I have plenty of character thank you very much!). Is there not a trolley you can use to collect several at the same time, that's what we did on the QM2, which has hundreds and hundreds of the blighters!

Think of it this way, when you're qualified, you will have your own cadet to do this for you, everyone has to do their time at the bottom of the heap!

[Randomist]

I am relatively sure that you're only supposed to test hoses with water. I could be wrong though.

[Steve]

Watertight is not equal to airtight. Test with water.

[YoungMariner]

Well this is one of the strangest things I've heard in a while. A surveyor would expect to see a pressure test with water. Normally 1 or 2 forward and 1 or 2 aft on upper decks would allow you one to check the hoses and then crack them open for a visual check of the pressure actual.

Air??????????????????????

[size4riggerboots]

AM, are you talking about testing the system or the hoses there? I think the OP is on about the test done on each and every hose to make sure it doesn't leak, you sound like you're on about the system pressure test?

[alistairuk]

On all the ships I have been on;

Testing the fire main / pumps (Weekly): Open the anchor wash valves and give the ECR the OK to commence testing the various pumps.

The testing of the hoses (not sure how often it's actually done - I think its 2 yearly - might be yearly); Take the hoses to mooring deck, connect em to a hydrant, open the valve, if water doesn't spew out of it, its ok.

Testing it with air - as s4 has said - how are you meant to see if it has holes?

As much as luging 100's of hoses to the mooring deck to test them is a pain in the ass - steal a shopping trolley from a supermarket in port somewhere and use that :-)

[YoungMariner]

Hi S4R, it's normally good practice to combine both tests. Initially you start with the nozzles closed, check for leaks under pressure, and then open them up for a visual check.
As Alistair says, it's worth opening the anchor wash valve so as not to overpressure the system and damage the pumps.

[Clanky]

Definitely only with water.

If a hose ruptures with air pressure inside it will have a lot more energy as the air expands than it would do as the water depressurises.

You won't necessarily find small leaks with an air test which would show up more obviously with water.

If you have 250 hoses then the answer is to split them into manageable chunks and do a few each week, try to come up with a plan which allows you to test some in position if cargo operation will allow it and try asking the engine room very nicely to test the engine room hoses.

[Chiefy]

To follow from clanky, normally the 3/o has a rota of hoses to do so x are done per / week month so all are tested usually twice / year.

You can combine the test with the system test, but we normally do that during fire drill instead.

Air is "explosive", 5 bar air is 5 times the volume in the same space (for rule of thumb) but 5 bar water is volume plus a tiny bit, if the hose burst the water just goes weep, if full of air all 5 volumes try to get out at one...it's the same reason you hydraulically pressure test Fire Extinguishers / pressure vessels

[Beef1992]

I agree with what chiefy says , tested with water as part of the 3/O PM's , With the computer system telling him which ones need testing each week.

And rather than steal a trolley like Alistair Suggested why not make one , Nothing better when there's no jobs to do then Making new tools in the work shop .