Life span of life jacket gas cylinder

[sealegsjim]

The life jackets I have on board are 4 years old and have never been worn and stored in dry conditions they look like new. They are the manual gas inflation type. Does anyone know the life span of the gas cylinders and are there any checks I can make? Thanks

 

[James_Calvert]

The filled weight should be printed on them. Check on the kitchen scales.

 

[Amulet]

The life jackets I have on board are 4 years old and have never been worn and stored in dry conditions they look like new. They are the manual gas inflation type. Does anyone know the life span of the gas cylinders and are there any checks I can make? Thanks

Weigh them - the correct weight should be stamped on them. If they are up to weight and not corroded they'll work. I have never seen expiry dates on them. They seem to last many years unless they get quite wet.

 

[prv]

The gas cylinders don't have an expiry date as such - that only applies to auto inflation mechanisms.

You should unscrew the cylinder and weigh it - you will find a "tare weight" stamped on the side and provided it still weighs at least that (or a couple of grams more) then it's still ok. Also check it's not significantly corroded.

You should unfold the jackets and inflate them manually through the oral tube - by mouth is ok, but I prefer to use a dinghy pump. Leave inflated overnight, and check they're still just as firm in the morning. Then inspect thoroughly for damage and wear before re-packing.

You could perhaps ease off the green plastic clip that holds the firing lever in position (saves breaking it and having to buy a new one) and pull the cord with the bottle removed to check that the pin inside moves up and down. But there's really no reason to suppose it wouldn't.

Pete

 

[jac]

On that subject, I've never been satisfied that ordinary kitchen scales are that accurate that they could distinguish between a full and empty 33gm cylinder.

Does anyone have a link to any scales that are known to be that accurate.

 

[andygc]

Does anyone have a link to any scales that are known to be that accurate.

Among many choices http://direct.asda.com/george/georg...-05eff6da2486&istItemId=xlwwmlxqa&istBid=tztx

The resolution is to 1 gm, so if it says test weight +1 gm, you should be happy.

 

[sailorman]

Among many choices http://direct.asda.com/george/georg...-05eff6da2486&istItemId=xlwwmlxqa&istBid=tztx

The resolution is to 1 gm, so if it says test weight +1 gm, you should be happy.

ebay £3.50 delivered i have these hanging up in my garage

http://www.ebay.co.uk/itm/40kg-Port...velTickets_Accessories_RL&hash=item3a7d93c131

 

[sealegsjim]

Thanks for all the useful advice. The forum never fails

 

[savageseadog]

They last a lifetime

 

[Slowtack]

Use digital kitchen scales

 

[Mistroma]

ebay £3.50 delivered i have these hanging up in my garage

http://www.ebay.co.uk/itm/40kg-Port...velTickets_Accessories_RL&hash=item3a7d93c131

Good for luggage as they have a max. of 40kg. However, the accuracy is only 10 gram and that's not good enough for these small cylinders.

I still have a couple of old crewsaver lifejackets circa. mid. 80s and the cylinders are still fine. I only keep them in case some foreign official insists on lifejackets for a full (but imaginary crew). They haven't been worn for many years but still get an annual check. No problem keeping inflated for a week and cylinders haven't lost any weight. I used to weigh them on laboratory scale but use digital kitchen scales nowadays. Still no sign of weight loss after about 30 years.

 

[skyflyer]

Among many choices http://direct.asda.com/george/georg...-05eff6da2486&istItemId=xlwwmlxqa&istBid=tztx

The resolution is to 1 gm, so if it says test weight +1 gm, you should be happy.

sorry to be pedantic but I recall a lesson in Physics at school pointing out that resolution and accuracy are not the same thing!

Having said that, in my experience digital kitchen scales are spot on, when I weigh a letter or small parcel and ale it to the post-office where they insist on checking it again!

accuracy-and-resolution-explained/

 

[Gumpy]

There you have the answer!
I take mine to the post office (it has digital scales) and ask them to weigh them.
Simple and no cost.

 

[sailorman]

Good for luggage as they have a max. of 40kg. However, the accuracy is only 10 gram and that's not good enough for these small cylinders.

I still have a couple of old crewsaver lifejackets circa. mid. 80s and the cylinders are still fine. I only keep them in case some foreign official insists on lifejackets for a full (but imaginary crew). They haven't been worn for many years but still get an annual check. No problem keeping inflated for a week and cylinders haven't lost any weight. I used to weigh them on laboratory scale but use digital kitchen scales nowadays. Still no sign of weight loss after about 30 years.

the cylinder weights are around 190gr

 

[Mistroma]

sorry to be pedantic but I recall a lesson in Physics at school pointing out that resolution and accuracy are not the same thing!

Having said that, in my experience digital kitchen scales are spot on, when I weigh a letter or small parcel and ale it to the post-office where they insist on checking it again!

accuracy-and-resolution-explained/

No, quite sensible and it used to be important when I worked in a laboratory. However, the scales on eBay only quoted "accuracy of 10 gm". I suspected that this was more likely to be the resolution rather than the accuracy but it wasn't relevant to the OP. The eBay scales would have an accuracy of 10 gm at best (lack of +/- 10gm might support it being resolution). Either way, not really the best choice test weigh lifejacket cylinders with 33 gm CO2.

 

[skyflyer]

http://www.ebay.co.uk/itm/Pocket-We...t=LH_DefaultDomain_3&var=&hash=item339aac3abc

these cost under a fiver, weight up to 500g and resolve to 0.1g so presumably are accurate within a few grams at worst

 

[Stork_III]

the cylinder weights are around 190gr

Depends which cylinder. 33g would be circa 136g

 

[Mistroma]

the cylinder weights are around 190gr

Yes, but the CO2 probably weighs around 33gms and I'd guessing that these only read to 10gms (see comments about resolution vs. accuracy). That would mean going up/down one unit on the scales covers 20gms. I wouldn't really buy these scales to test lifejacket cylinders.

 

[jac]

These look even more accurate. Down to 0.01g resolution up to max 200g. Lifejackets are on board now but anyone know what a full cylinder would weigh?

http://www.amazon.co.uk/DIGITAL-WEIGHING-KITCHEN-JEWELLERY-0-01G-200G/dp/B00JDMJ3SG/ref=pd_cp_kh_3

 

[Mistroma]

http://www.ebay.co.uk/itm/Pocket-We...t=LH_DefaultDomain_3&var=&hash=item339aac3abc

these cost under a fiver, weight up to 500g and resolve to 0.1g so presumably are accurate within a few grams at worst

Good find, they look fit for the job.

I had another look at the other one sailorman suggested and see the display shows 0.00 in one picture. That would be in line with a resolution of 10 gms (0.01 kg), actual accuracy will be considerably worse.