Gas Bottle Sizes and Uses
Gas bottles come in a huge range of sizes and materials to suit where and how they are being used , from smaller gas bottles for summer BBQs on the beach to larger gas bottles for water heating at home.
In this article we will talk about the most common types of gas bottles found here in NZ, different materials they are made from, what they are best used for and where they can be found.
First and most commonly used gas bottle has to be the standard 9kg LPG gas bottle. Usually constructed from steel or can also be made from aluminium. These gas bottles are found typically on BBQs and Patio heaters as they are very portable and last longer than a smaller 2kg or 4kg gas bottles this size can also be used for a gas hob at home typically lasting between 1-3 months in the average home depending on usage. These gas bottles are also the most easily accessible as many building supply shops and gas stations will have them available to swap or fill for convenience.
Another commonly seen and used gas bottle is the larger 45kg LPG bottles. Also typically made from steel or aluminium These are usually found in residential areas where reticulated gas isn’t available and in some commercial situations. Best for cooking , water heating and gas fires, 2 x 45kg gas bottles are usually installed and fitted with gas regulators and linked by a change over valve which will inform the gas delivery driver which gas bottle is empty and needs replacing.
As the 45kg gas bottles are delivered, sites must be easily accessible and this will be a requirement from the gas suppliers before they are installed at any location.
In-between 9kg and 45kg gas bottles are the 12kg, 15kg and 18kg sizes, these gas bottles are primarily made of steel or if used on marine installations can be made from marine grade alloy. These sizes are not generally used in residential areas.12kg gas bottles are preferred by small commercial establishments and sometimes used on caravans and boats where gas consumption is higher than what a 9kg bottle can handle. This is especially true on food and coffee caravans , as this size is still small and portable enough to take and get refilled and has a longer duration time. There are a limited number of gas suppliers who will refill this size or deliver it to consumers especially if the access is more difficult, so checking with your local gas supplier is best before installing a 12kg gas bottle on a site.
18kg and 15kg LPG gas bottles are again most suited for small scale commercial use such as kitchens and restaurants to minimise refilling but keeping costs down by not installing a 45kg bottle when it is not needed. 15kg LPG gas bottles are also used as fuel to power forklift trucks and other industrial vehicles, if used in this situation the bottles are normally constructed of aluminium to help keep the vehicles lightweight.
Gas Bottle Safety
There are a lot of rules about where you can locate gas bottles. Including internal and external locations.
They do not like gas bottles inside a building. There is the obvious risk of having a bottle inside where there is a fire risk.
Fire fighters are not happy about entering a building where there is a bottle inside if the building is on fire.
There is the risk of gas leaking inside at the bottle connections and Propane/Butane is heavier than air so it drops to the floor and accumulates.
This is why there are so many rules about bottles inside and it is only done if the bottle is small, and for a particular use and, it is not near a source of ignition like a cooker or hob,
Or some other manufacturing process.
It is tempting to put gas bottles next to where you are cooking, but his is a no no. The risk of bottle leakages is too high and the risk of the leak catching fire is high, and the damage to you and the building is not acceptable. When you know the risks it is better to keep the bottle outside.
It is important that the rules are followed from an insurance perspective as many policies insist the situation is legal to get cover.
Bottles are usually outside on firm ground like concrete tile, or slab like a driveway or foot path. If they are in garden areas they are on a slab or large 50mm thick tile.
Ensure bottles are not near openings into a building the 1m rule applies. The bottle must be restrained usually with a chain.
Not under overhangs unless they are small like not more than 800mm.
On boats the bottle must be in a locker just for the bottle, and have a ventilation opening at the bottom not less than 19mm.
Caravans and Motor Homes
The bottle must be in an enclosure and vented to the outside with two vents on at the top and one at the bottom. It pays to keep the bottle restrained. Just imagine going over a bumpy road you don’t want that bottle bouncing around.
The same applies to boats imagine the boat sailing over large wages and chop and the bottle bouncing around ensure it is secured well and there is nothing in that enclosure that would damage the piping if it was thrown around.
All bottle regulators have over pressure relief so this is why it is important to have any enclosure well ventilated. If the bottle is outside and the piping heads inside what happens to vented gas. The regulators used for barbecues and gas installations are different. The barbecue regulator is designed for outside use. The regulator used for gas installations has a relief vent and that gas has to go somewhere hence the vented enclosure or there is a pipe installed for this gas to go somewhere outside.
If you are not sure get a qualified gas fitter to visit and the the installation a check over.
Gas is usually very safe so long as it is respected.