Back to basics: cellar gas safety

As more pubs have become independent of brewers over the last 15 years or so the impact has not just been on the beer on the bar. The freeing of the tie has also brought more dispense gas suppliers into the market - and the result is an increase in dangerous incidents caused by failing gas cylinders.

It doesn't just affect the pub industry, but licensees in particular have been tempted by cheap offers from new local suppliers - at the risk of using cylinders that haven't been put through the necessary safety tests.

Life-threatening incidents are still rare - but they are rising in number. Between 2000 and 2003, 18 were reported compared to only three between 1994 and 1999.

Now one of the country's biggest reputable suppliers has launched a safety offensive to raise awareness among licensees of the dangers and to clear the trade of potentially unsafe cylinders.

BOC Sureserve has 53,000 hospitality customers and 700,000 of the four million gas cylinders out there, but it has seen its market share eroded by local suppliers.

The worry is that's not the only thing being eroded. Compressed gas cylinders should be tested every five to 10 years, depending on the mix of gases they contain.

The most common problem with an old cylinder is a leaking valve which allows moisture to mix with the carbon dioxide causing corrosion and weak spots.

If CO2 leaks into your cellar the gas, which is heavier than air, can build up in pools over a period of time. Anyone going down into the cellar is then at risk of asphyxiation.

In the course of a year BOC Suresave alone tests 80,000 cylinders and scraps 3,000 of them. As the company's product manager Piers Capper points out, there is no way to be sure that the new breed of unregulated supplier is carrying out such tests.

"We find a lot of used competitor cylinders lying around at our customers' pubs," he says. "It's a safety issue.

"Not only do they clutter the cellar but they might taken away by an unscrupulous supplier and be refilled without safety checks.

"Because of the number of new people coming into the industry, licensees are not always aware of the risks. Incidents are very rare but you have to ask whether that's a matter or luck or judgement."

BOC Suresave has joined forces with Kegwatch, which gathers up uncollected kegs around the trade, to trial a scheme this month that will see the organisation picking up forgotten cylinders too.

It is also making extra efforts to make sure safety information gets to licensees so they can carry out their own checks on cylinders.

BOC Sureserve's top 10 tips for cellar gas safety:

1 Use a reputable supplier​

A reputable supplier is one who can supply cylinders that meet industry safety standards for food grade dispense gases. They will normally be a member of the British Compressed Gas Association.

Key things to check for are:

- Positive pressure valves. These valves prevent moisture getting in and corroding the cylinder

- Correct valve outlets to ensure that high-pressure mixed gas is not put onto a low pressure CO2 regulator

- That the cylinder label carries all the necessary information: size, quality standard, nominal weight, nominal pressure, safety advice, dangerous goods information and suppliers contact details including emergency telephone number. All these are required by law. If your cylinders don't carry all this information, send them back

- Safety data sheets. These should be supplied with your first delivery, but they can also be downloaded free from www.bocsureserve.co.uk

- Test cylinders frequently. Every cylinder should have a coloured ring attached to the valve indicating when it is due for removal and testing by your gas provider. Dispense gases due for removal in 2006 will carry a grey hexagonal tag. It's a red square for 2007

- Correct cylinder body colour, generally black or grey for CO2, grey with green or black shoulders for mixed gas, brown for balloon gas. There are some variations because of revisions to international standards

- Cylinders that are food grade quality. CO2-dispense gas cylinders should be supplied to recognised food grade standards

2 Assess your cellar to reduce risk​

This is a legal requirement for every licensee. You can either self assess, there's a step-by-step guide in the BOC Sureserve risk assessment pack, or for extra peace of mind get a gas expert to do it for you.

To reduce any risks identified by the assessment you should then develop an action plan, keeping a running record of the actions you take. Your plan should include steps to mitigate against a gas leak such as installing CO2 monitoring and detection equipment, increasing cellar ventilation and setting out emergency procedures.

And if you are going to the cellar always tell a colleague and say how long you expect to be.

3 Don't overstock ​

Too many cylinders will compromise space in the cellar and if not properly secured, can present a tripping hazard.

Keep only the amount of cylinders suitable for your business needs. Your gas provider will be able to give advice on how many beer barrels can be supplied from each cylinder size. Using blending equipment will help keep cylinders at an optimum number as you will only need two types of gas. CO2 and 70/30 mixed gas.

4 Never tamper with a cylinder​

But do ensure all connections and joints are gas tight and do not leak.

Testing for a leak is easily done by spraying an ammonia-free leak-detection solution on all cylinder connections (ammonia reacts with brass and can corode fittings). If frothing or bubbling occurs you have a leak. The gas should be turned off immediately and the connection secured before the cylinder can be used again.

5 Never connect cylinders to a keg directly​

Always use a suitable regulator. The job of the regulator is to ensure that the correct gas pressure is supplied to the keg. Without it you risk serious personal injury to yourself or your staff.

6 Never throw or drop cylinders​

Dispense gases are compressed under enormously high pressure. Dropping or throwing a cylinder risks damaging the valve and causing the cylinder to leak, which in a cellar can create an unsafe environment and cause CO2 poisoning or asphyxiation..

7 Store cylinders correctly​

If they are full they should be kept in an upright position, securely fastened to the wall. Empties can be laid down and chocked to prevent any movement. Always keep gas cylinders in a secure environment.

8 Store in a ventilated area​

Store cylinders in a ventilated area wherever possible. Forced ventilation can be used if stored indoors.

9 Ensure correct mix of dispense gases is used​

Using the correct mix reduces fobbing and wastage. There are generally three mixes used in the UK:

- 30/70 (CO2/N2) for low carbonated ales and stouts

- 60/40 (CO2/N2) for lagers and ciders

- 50/50 (CO2/N2) used by certain brewers for some smooth beers and ciders.

10 Train your staff​

Ensure that any staff members who change gas cylinders are trained in their safe storage and handling. Being able to spot the tell-tale signs of a gas leakage - such as condensation build-up on a cylinder or loss of pressure on the regulators when the cylinder is turned off - all helps contribute to working in a safe environment.