Gas Safety · Practical guide
Who can legally carry out gas work in Great Britain?
The difference between competence and Gas Safe registration, what counts as gas work, and how to check an engineer.
The short answer
What you need to know
Anyone carrying out work on a gas fitting or gas storage vessel must be competent for that work. For gas engineering businesses doing work within the Gas Safety (Installation and Use) Regulations, the business must also be on the Gas Safe Register; a self-employed engineer doing their own business work needs registration too. An engineer’s registration must cover the kind of gas and appliance involved. Some activities and premises fall outside the registration rule, but competence and other safety duties can still apply.
The detail
Understanding the requirements
Competence applies to the person doing the work
Regulation 3(1) in L56 says no person may work on a gas fitting or gas storage vessel unless competent to do so. HSE describes competence as the practical skill, training, knowledge and experience needed for the particular task, including leaving the installation safe. An engineer qualified for one appliance or fuel is not automatically qualified for every gas task.
Employers and others controlling gas work must ensure the person doing it is competent. L56 says even unpaid work or a favour for a friend falls within the wide meaning of gas work and still requires competence. This is a legal distinction, not an invitation to attempt gas work without the necessary skills.
Business gas work also needs registration
Regulation 3(3) adds a separate requirement for employers and self-employed people doing gas-fitting or service-pipework within its scope: they must belong to an HSE-approved class of persons. HSE identifies the Gas Safe Register as the approved registration scheme. An engineer employed by a registered business can work under that business’s membership; if they take separate work on their own behalf, L56 says they need registration in their own right.
Regulation 4 also requires an employer or self-employed person who arranges or controls gas-fitting work at a workplace to take reasonable steps to check that the person doing it is, or works for, a registered business. Ask to see the engineer’s Gas Safe ID card and check the categories on the reverse against the appliance and fuel. HSE also points to the Register’s online checking service.
Check what the rules cover
L56 defines gas work broadly: installing, reconnecting, maintaining, servicing, repairing, altering, purging and removing a gas fitting are among the covered activities. Some actions, such as lighting a pilot light, are not themselves gas work. The law has narrow exceptions to the registration requirement for specified hose or regulator replacements, and L56 explains that some premises fall outside GSIUR. These exceptions do not mean the activity is automatically safe for an untrained person.
For a job at an excluded industrial site, HSE says competence is still required under general health and safety duties even where Gas Safe membership is not required by GSIUR. If the scope is uncertain, identify the precise fitting, premises and task before deciding who may do the work.
Trace the answer
What the official guidance says
Source notes below are Falstaff summaries. Text in quotation marks is a short excerpt from the linked official source.
Health and Safety Executive · Regulation 2(1), meaning of “work” · Falstaff chunks d5da588b, d6dcc783
Gas Safety (Installation and Use) Regulations 1998: Approved Code of Practice and guidance (L56)
Falstaff source note: Defines covered activities and explains that unpaid or do-it-yourself work still requires competence.
HSE L56, fifth edition (2018). Falstaff holds the regulation, ACOP and guidance passages.
Health and Safety Executive · Regulation 3(1)–(2), competence · Falstaff chunks be812747, 451e1e0b, de777424
Gas Safety (Installation and Use) Regulations 1998: Approved Code of Practice and guidance (L56)
Falstaff source note: The stored regulation and guidance require competence for the person and explain what competence means for the specific task.
HSE L56, fifth edition (2018). Falstaff holds the regulation, ACOP and guidance passages.
Health and Safety Executive · Regulation 3(3), approved membership · Falstaff chunks 4b89cd21, c124207c
Gas Safety (Installation and Use) Regulations 1998: Approved Code of Practice and guidance (L56)
Falstaff source note: Sets the separate membership requirement for employers and self-employed gas businesses; L56 explains own-account work.
HSE L56, fifth edition (2018). Falstaff holds the regulation, ACOP and guidance passages.
Health and Safety Executive · Regulation 3(4) and guidance · Falstaff chunks 71c6ef72, f4866e36, 14f4f85c
Gas Safety (Installation and Use) Regulations 1998: Approved Code of Practice and guidance (L56)
Falstaff source note: Describes limited registration exceptions and circumstances outside GSIUR, while retaining the competence distinction.
HSE L56, fifth edition (2018). Falstaff holds the regulation, ACOP and guidance passages.
Health and Safety Executive · Regulation 4, duty to check · Falstaff chunks 1f45674f, 857b0626
Gas Safety (Installation and Use) Regulations 1998: Approved Code of Practice and guidance (L56)
Falstaff source note: Requires reasonable steps when arranging gas work at a workplace; HSE guidance points to the engineer’s permitted scope.
HSE L56, fifth edition (2018). Falstaff holds the regulation, ACOP and guidance passages.
Health and Safety Executive · Gas Safe Register and engineer identity cards
Gas Safe Register
Falstaff source note: Current HSE page confirms the scheme and explains that ID cards show the categories of work an engineer is qualified to undertake.
Live HSE explanation of business registration and engineer identity cards; not stored as a Falstaff document.
Practical considerations
These examples help frame a site-specific assessment. Check the current official sources before making a compliance decision.
- Describe the gas, appliance, fitting and exact task when booking an engineer.
- Check both the business registration and the engineer’s ID card, including the work categories and expiry date.
- Do not treat a general plumbing qualification or experience with another appliance as proof of gas competence.
- If the work is outside ordinary domestic or commercial premises, check whether GSIUR applies before assuming the same registration rule.
- For a landlord safety check, use a Gas Safe registered engineer qualified for that work.