Under Regulation 2016/426 as it applies in Great Britain, a gas boiler must meet essential safety requirements, undergo third-party conformity assessment and carry a UKCA or CE marking before it is placed on the market, and the manufacturer, importer and distributor each have legal duties that OPSS guidance sets out.

Which rules apply and where

The Office for Product Safety and Standards (OPSS) explains that Regulation 2016/426 on appliances burning gaseous fuels, as amended to apply in Great Britain, sets the essential requirements that must be met before gas appliances or fittings can be placed on the GB market, and that the Gas Appliances (Enforcement) and Miscellaneous Amendments Regulations 2018 provide for enforcement. The guidance, last updated on 24 March 2025, covers England, Scotland and Wales, and separate guidance applies in Northern Ireland, where the EU regulation continues to apply under the Windsor Framework. Gas appliances placed on the market before 21 April 2018 remain regulated under the earlier Gas Appliances (Safety) Regulations 1995.

What the regulation covers

According to OPSS, the regulations apply to appliances burning gaseous fuels used for cooking, refrigeration, air-conditioning, space heating, hot water production, lighting and washing, as well as forced draught burners and heating bodies to be fitted with them, and to fittings that are regulating, controlling or safety devices. A gas boiler for space heating and hot water is therefore in scope. Appliances specifically designed for industrial processes on industrial premises, for aircraft and railways, for research or for temporary laboratory use are outside it. This is separate from the installer-side rules explained in our guide to regulation 26 of the Gas Safety (Installation and Use) Regulations.

The essential requirements

The essential requirements in Annex I are compulsory, and every appliance in scope must go through a conformity assessment procedure. OPSS highlights that appliances must be designed to operate safely and present no danger to persons, domestic animals or property in normal use, that the manufacturer must analyse risks and design with them in mind, and that reasonably foreseeable uses as well as the intended use must be considered. Each appliance must come with installation instructions for the installer and instructions for use and servicing for the user, and with warning notices on the appliance and its packaging stating the gas type, supply pressure, appliance category and restrictions such as the need for sufficient ventilation.

UKCA and CE marks

OPSS says that since 1 October 2024 businesses can use either UKCA or CE marking to place goods on the GB market, following legislation that extended recognition of CE marking indefinitely. A product assessed by a UK Approved Body must be UKCA marked, while one assessed by an EU notified body can be CE marked, and from 1 October 2024 can also be UKCA marked in certain circumstances. A product can be dual marked where the conditions are met. The mark must be affixed visibly, legibly and indelibly to the appliance or its data plate, or to the packaging and documents where that is not possible. The manufacturer draws up a declaration of conformity and must keep it and the technical documentation for 10 years after the appliance is placed on the market.

Manufacturers, importers and distributors

The manufacturer carries the main responsibility, including third-party conformity assessment, type and serial or batch numbering, a name and postal address on the appliance, and instructions in easily understandable English. Importers, who bring appliances into GB from outside the UK, must check that the manufacturer completed the required procedures, that the appliance bears the correct marking and documents, and that the manufacturer’s contact details appear; OPSS notes a transitional easement to 31 December 2027 allowing importer details on packaging or documents. Distributors, meaning anyone else in the supply chain, must check the marking, instructions and labelling before making an appliance available, store and transport it safely, and take or notify corrective action if they have reason to believe it does not conform.

Enforcement and penalties

OPSS explains that local trading standards authorities enforce the regulations for appliances for private use, and the Health and Safety Executive for workplace use, with the Secretary of State also having enforcement powers. Enforcement authorities can act against economic operators for products that present a risk or do not conform. OPSS states that offences can lead to a fine or, for the most serious offences, a prison sentence of up to two years, and that prosecution is a decision for the enforcement authority and the court. A recalled model can be checked using the approach in our guide to boiler product recalls.

What a buyer can check

The guidance is addressed to businesses rather than householders, so it does not set out a buyer’s checklist. It does make clear what should accompany a compliant appliance, and a buyer can look for a UKCA or CE mark on the appliance or data plate, a manufacturer name and address, instructions in English and warning notices. Extra care applies to second-hand or ex-display units, as discussed in our guide to second-hand and ex-display boilers.

FAQs

Can a boiler have a CE mark instead of UKCA in Great Britain?

Yes. OPSS says CE marking is recognised indefinitely in Great Britain from 1 October 2024, so businesses can use either mark, subject to the conformity assessment conditions.

Who enforces these rules?

For appliances for private use, local trading standards authorities, according to OPSS. The HSE enforces for workplace use.

Does the guidance apply in Northern Ireland?

No. OPSS provides separate guidance for Northern Ireland, where different marking arrangements apply.

The bottom line

A gas boiler placed on the market in Great Britain must meet Regulation 2016/426, be conformity assessed and carry a UKCA or CE mark, with defined duties on manufacturers, importers and distributors and enforcement by trading standards. The mark is evidence of assessment against essential safety requirements, not of a good installation, which is governed by separate rules on registration, installation and commissioning. This is general information, not regulated advice on any specific installation.

Sources

This guide draws on the following primary sources, current as of 24 September 2026:

• Office for Product Safety and Standards, “Regulation 2016/426 and the Gas Appliances (Enforcement) and Miscellaneous Amendments Regulations 2018: Great Britain” (March 2025), GOV.UK
• Office for Product Safety and Standards, “Gas Appliances (Enforcement) Regulations 2018” (last updated 24 March 2025), GOV.UK

Related guides

Best Boiler Deals is an independent guide. We may earn a fee from some links; this never affects what we write. This article is general information, not regulated advice on any specific installation — always confirm the details with a Gas Safe registered engineer.