Petrol at home: the risks and the law

Some of this info has since been updated - see notes at the end

Not an April Fuel's Joke?

The standard UN-approved 20L jerrican omits statutory labelling for fuel storage at home. And it's 2x too big.In a TV news clip filmed during the recent petrol panic, I saw a guy at a filling station loading maybe ten 20 litre jerricans of petrol, the equivalent of a 45 gallon drum, INTO his car’s passenger compartment (it was a hatch). They were plain standard-issue green NATO style / UN 20 litre cans, stacked flat and upright.

First problem is, if there was any form of petrol vapour leak, or maybe a pocket of fumes building up in the car, then a single spark from an electrical circuit, or static electricity spark (do you ever get static shocks from your car upholstery?), or a spark induced by a radio circuit or mobile phone could ignite the fumes and cause an explosion. It would have destroyed the car and probably killed the driver.

If there were a car accident (e.g. he was hit from behind) then because jerricans are not crash-proof there’d be the same risk of fire or explosion given that the car could be carrying about 60 gallons in total. Or some of the loosely-stacked jerricans would carry on travelling at 60 or 70mph and kill the driver that way instead.

However, the various transport regulations (fire extinguisher, container labelling, documentation etc.) for this kind of quantity don't seem to apply to the private carriage of fuel this way, according to the HSE. It's still highly dangerous to have an insecure, unlabelled load of 20L jerricans transported inside a car though. It's not even advisable to carry any petrol inside the car at all.

Vapourised

Not everyone understands that petrol is nothing like paraffin (kerosene) or terpentine.  It’s the invisible vapour of petrol that ignites, not the liquid itself, which is why an electric fuel pump can safely be immersed in a car’s petrol tank, and why it takes a spark plug to ignite the fuel-air mixture in an internal combustion engine.

In York today it’s reported that a woman was decanting petrol from one container (a proper fuel can) into a jug in her kitchen when the invisible explosive fumes flashed over – her cooker was turned on nearby, and this ignited the petrol fumes which exploded.  She was taken to hospital with 40% burns. BBC News report. 

Petrol laws

The UK legislation about fuel storage at home (or work) first took shape in the Petroleum Spirit (Motor Vehicles &c) Regulations, 1929. I believe that in the 1920’s, when motorists, pilots and boat owners could store fuel in large drums, there were so many fuel fires and accidents that laws controlling the storage of gasoline had to be introduced: drivers just sloshed petrol around in an open-top drum in the garage! The original laws are here (PDF) and are interesting reading. They're quite digestible.

The law was updated in the 80’s to allow some plastic containers to be used for storage as well. They have to be solvent and UV proof and properly labelled. (Many cars have plastic petrol tanks these days too.)  See the Petroleum-Spirit (Plastic Containers) Regulations 1982.

All petrol containers should be marked “Petroleum Spirit Highly Inflammable” [that guy’s 10 jerrican’s were obviously not]. Really, the “Highly Flammable” hazard warning is a misnomer – it gives the impression that petrol merely "burns" like paraffin, but it should say “Highly Explosive In Air” instead, to drive the message home that it's more explosive than TNT when it ignites.

Legal Limits on petrol storage at home

There’s a legal limit (UK) as to how much petrol you can store at home (in a garage, or within 6 metres of a building).

At the time of writing you can keep no more than:

• two 10 litre metal petrol cans in a garage, and
• two 5 litre plastic petrol storage containers.

I found some discrepancies between various authorities about this. The HSE states in its FAQ that you can keep up to 30 (20 + 10) litres stored as above.

This includes petrol stored in containers kept in any parked cars, but not the fuel tanks themselves.  You shouldn't keep any petrol indoors at home whatsoever due to the explosion risk from fumes leaking in an enclosed space. Storing quantities larger than these requires the Petroleum Licensing Authority to be informed, and storing more than 275 litres also needs a licence.

The Regs. also relate to building design and fire protection (hardwood internal door with closer, directly open to fresh air and not an 'internal' room, fire resistant ceilings, etc.) eg if you have a built-in garage like I do, which in theory could hold 100+ litres of fuel in the cars.

It would have been interesting to see what someone with 200 litres in jerricans planned to do with them all.

The best source of advice is probably the Health & Safety Executive website. Although the HSE is industry and workplace-related, there’s some useful information on home storage of fuel in its FAQ here.

 

Update on Thursday, March 12, 2015 at 9:05PM by Alan W

Says the HSE, you can store up to 30 litres of petrol at home or at non-workplace premises without  informing your local Petroleum Enforcement Authority (PEA).

The Petroleum (Consolidation) Regulations 2014 came into effect on 1st October 2014.

You can store petrol in:

• suitable portable metal or plastic containers [it seems that 20L NATO/ UN petrol jerricans are now acceptable containers for storage at home]
• one demountable fuel tank
• a combination of the above as long as no more than 30 litres is kept.

See http://www.hse.gov.uk/fireandexplosion/petrol-storage-club-association.htm

and download this PDF from the HSE too. Many if not most petrol containers still omit the statutory hazard label.