Gas work is the one trade on this site where the law decides who may do the job at all. The Gas Safety (Installation and Use) Regulations 1998 make it an offence for anybody not on the approved register to carry out work on gas fittings, and an engineer's insurance sits entirely on top of that: the policy assumes registration, the underwriting asks about it, and a claim will be checked against it before anything else.
Registration is the precondition, not a discount
An insurer writing gas work expects the engineer to be on the Gas Safe Register for the categories of work being done, and will ask which. This is different from the voluntary schemes in other trades. An engineer whose registration has lapsed, or who works outside the categories they hold, is not simply paying the wrong premium; the work itself is unlawful and the claim that follows is very hard to defend.
The claims that make this the most expensive trade to insure
Two claim types dominate and both are severe. Carbon monoxide exposure from a badly installed or unswept appliance causes injury or death and produces claims that reach the top of a policy limit. Gas escapes and explosions damage buildings and their neighbours. Neither is common, and their severity is why gas is rated separately from plumbing and why the published cost per click on this question is the highest on this site.
Landlord certificates and the paper trail
Gas engineers issue records that other people rely on: the landlord gas safety record, commissioning documents, service records. Those are professional acts as much as physical ones, and an error in one can produce a claim for financial loss as well as for injury. Engineers who certify should ask specifically whether their policy reaches that, because a plain public liability section answers for damage rather than for a negligent certificate.
Buying it alongside plumbing work
Most gas engineers also plumb, and insurers rate the two together with gas declared on the schedule. The hot works condition still applies to any soldering, the escape of water exposure still applies to the plumbing half, and the limit is normally set by the buildings worked in: five million pounds for flats, commercial premises and contractor work.
Questions people ask about gas engineer public liability insurance
Do gas engineers need public liability insurance by law?
No statute requires public liability, but Gas Safe registration is a legal requirement for the work itself, and employers' liability is compulsory once anybody is employed. In practice landlords, agents and contractors all require public liability before engaging an engineer.
Does insurance cover work outside my Gas Safe categories?
It should not be relied on to. Working outside the categories held is unlawful under the 1998 Regulations, and an insurer told the engineer was registered for the work will treat a claim arising from unregistered work very differently.
How much cover do gas engineers need?
Two million pounds is a floor for domestic work and five million is the usual requirement for flats, commercial premises and contractor work. Given the severity of carbon monoxide and explosion claims, the higher limit is the sensible default rather than the contractual minimum.
Are landlord gas safety records covered?
A negligent certificate is a professional act producing financial loss as well as potential injury. Ask specifically whether the policy carries professional indemnity or an equivalent extension, because a plain liability section is written around physical damage.