How Safe is Your yacht's Gas System? Part 2: Bottles & Bottle Storage

From yachtandboat.co.au

Following on from Part 1 on Gas Installation standards, we start to look at practical installation pointers with a section on gas bottles and bottle storage.

Bottles & Bottle Storage

Boaters normally acquire their gas bottles from the gas supply companies.  Bottles tend to be of steel or aluminium construction and will have been manufactured to comply with national quality standards.  Overseas, it’s possible to buy gas bottles from local gas suppliers, or from chandlery shops.  Aluminium is a favourite in the chandlers due to its light weight, but the see-through fiberglass bottle is rapidly gaining popularity.  Fibreglass tanks have been approved by ABYC (check for the mark of approval) but, at the time of writing, have yet to be accepted by the European Union as ISO compliant.

If you're buying a new gas bottle, be sure to check it carries the necessary kite mark or other symbol indicating compliance with your required standard.

Lite Fibreglass LPG Tank

Gas bottles must be stored in a dedicated gas locker (or outside) such that, should a gas bottle fail for any reason, it has no possibility of discharging into the cabin space.  In real terms this means that:

1. If stored outside, the bottles must be in a place where they are sheltered from damage in the event of a collision, and far enough away from entrances to the living space so that escaping gas will not enter.
   
   
2. Lockers must be made of a non-permeable material resistant to heat, with a rubberized sealing gasket and preferably top opening.  They must be maintained in good condition and regularly inspected, especially at the seams.
   
   
3. Lockers should be big enough to contain the bottle(s) and all associated switching valves & bubble leak detector to the point where the highest exit point is the tube taking the gas to the appliances.
   
   
4. Lockers should have a drain large enough to carry any leaked gas quickly out of the vessel; the pipe or vent should exit the locker at the bottom, so that gas can’t accumulate in the locker floor, and the vent must discharge over board, above the waterline.  If using a pipe, it should be of ISO approved non-combustible material and preferably ¾ inch in diameter.
   
   

   

   From BSS Guide Chapter 7
5. There should be a good seal at the point where the pipe taking the gas to the appliance exits the locker, either using a bulkhead fitting or cable gland.
   
   
6. Gas bottles should be secured in an upright position within the locker and, to the extent that they might move, must not pull on, or cause stress to any associated pipework.

 Gas lockers are usually built into the boat, normally in the cockpit area at the time of manufacture so as to comply with latest manufacturing standards, however they can also be retrofitted, and it is possible to buy freestanding lockers from the likes of Trident Marine.

Dedicated Propane Locker

In Part 3: Pipes, Hoses & Joints