Gas Safe RAMS Guide for UK Contractors

Key Topics in a Gas Safe RAMS

Gas Safe registration and competence boundaries

Every engineer carrying out gas work must be registered with the Gas Safe Register for the specific appliance category and work type — for example, domestic natural gas boilers (CCN1), domestic LPG (CPA1), or commercial catering gas (CCLP1). An engineer registered for one appliance category is not automatically registered for another. The RAMS must confirm the specific Gas Safe registration held by each operative and confirm that it covers the scope of work to be carried out. Gas Safe registration can be verified at gassaferegister.co.uk. Gas work on gas fittings by unregistered engineers is a criminal offence under GS(IU)R 1998.

Gas isolation and tightness testing

Before and after any work on gas pipework or appliances, a gas tightness test must be carried out to confirm there are no leaks. The test uses a pressure gauge (U-gauge or electronic manometer) to measure pressure drop over a specified time period. Acceptable tolerances are set in BS 6891 for domestic systems and IGE/UP/1B or IGEM/UP/1C for commercial and industrial systems. The RAMS must describe: the isolation point (meter, service valve, or appliance valve); the purging procedure for removing gas from the line; the tightness test procedure and pass criteria; the reinstatement and re-commissioning procedure; and the record format for the test result. No gas appliance may be commissioned without a passed tightness test.

Carbon monoxide detection and combustion analysis

Carbon monoxide (CO) is a colourless, odourless gas produced by incomplete combustion in gas appliances. CO poisoning is a risk from faulty, unserviced, or incorrectly installed appliances and from blocked or poorly-draught flues. The RAMS must require: a personal CO alarm carried by every engineer; CO measurement during combustion analysis on every appliance serviced or commissioned; flue condition and draught assessment before firing any appliance; an escalation procedure if CO levels exceed the HSE-recommended ambient level of 20 ppm (occupational action level) or the appliance fails combustion analysis. The RAMS must confirm that no appliance is commissioned or left in service if it fails a combustion analysis or CO check.

Emergency gas leak response — 0800 111 999

In the event of a gas leak or strong gas odour, the emergency procedure is: do not operate any electrical switches; extinguish all naked flames; open doors and windows; turn off the gas at the emergency control valve; evacuate the building; call the National Gas Emergency Service on 0800 111 999 (24 hours, free). This number and procedure must be included in every gas work RAMS and displayed at the site. The RAMS must also describe the on-site engineer's response to a gas smell during work — including stopping all work, ventilating the area, and checking with a gas detector before proceeding.