The UK gas engineer compliance checklist.

Registration is the law, not a badge

Any gas work carried out as a business must be done by a Gas Safe registered engineer. Unregistered gas work is a criminal offence under the Gas Safety (Installation and Use) Regulations 1998. This is not a scheme preference; it is the licence to trade.

Registration runs on two clocks. The business registration renews annually. Each engineer’s ACS competence assessments last 5 years, and every category of work you do (boilers, cookers, fires, commercial catering) has to be in date. Let an ACS element expire and you cannot lawfully do that work until you are reassessed.

Landlord work: the record-keeping trap

Landlord gas safety checks are annual, and the record (the form still widely called a CP12) has legally required contents: each appliance and flue checked, the engineer’s name, registration number and signature, the dates, the defects found and the action taken.

The landlord must give existing tenants a copy within 28 days of the check and keep records for at least two years. Landlords lean on their engineer to get this right: an incomplete record is a compliance failure for the client and a reputation problem for the firm that issued it.

Fitting appliances: the building-regs notification

Installing a heat-producing gas appliance, such as a boiler or a fire, is building-regulations work as well as gas work. Registered businesses self-certify it, and the Building Regulations require the local authority to be notified and the customer to receive a Building Regulations compliance certificate within 30 days of completion (Building Regulations 2010, regulation 20).

This is the notification firms most often miss in a busy month, and the customer usually only discovers the gap years later, at the point of sale.

Where gas businesses most often slip

Three patterns dominate: an ACS element quietly expiring so part of the workload becomes unlawful overnight; the annual business registration renewal treated as routine until it is missed; and appliance installations that never get notified. None of them are competence problems. All of them are date problems.