What is a CP17 commercial gas safety record?

CP17 is a form code rather than a class of legal document. It is the record of a gas safety inspection at a workplace, published by CORGIdirect as the Gas Installation Safety Report (Non Domestic), and it is what a facilities manager, an insurer or an environmental health officer means when they ask a business for its commercial gas certificate. The duty behind it fits in a single sentence of the 1998 regulations, and the 12-month interval everyone quotes as law is not in that sentence.

What is a CP17?

A CP17 is the Gas Installation Safety Report (Non Domestic): the form a Gas Safe registered engineer completes after inspecting the gas installation serving a commercial premises. CORGIdirect publishes it as one of the CP-series forms that came out of CORGI and stayed in trade use after Gas Safe Register took over registration, and sells it as a pad of 50 single-part NCR forms at £8.00 excluding VAT. The same form is built into most job-management apps. The current version separates appliance details from inspection findings into two blocks, a change that cut the form from eight gas appliances to four, so older eight-appliance layouts are still in circulation. No regulation names the form. What the law asks for is an installation maintained in a safe condition and, when someone asks, evidence that a competent person checked it, which is the job a completed CP17 does.

What does a CP17 record?

Nine blocks, running from the business and job details through to the engineer's declaration. The structure is worth reading before a first commercial inspection, because the fields say what the visit has to produce: an operating pressure or heat input and a combustion analyser reading at every appliance, a strength and tightness test result on the pipework, and a plain yes or no on whether each appliance is safe to use.

Which premises need a CP17?

Any workplace with a gas installation. Regulation 35 of the Gas Safety (Installation and Use) Regulations 1998 is one sentence: every employer and self-employed person must ensure that any gas appliance, installation pipework or flue installed at any place of work under their control is maintained in a safe condition so as to prevent risk of injury to any person. That reaches offices and shops, pubs and restaurants, schools, churches and village halls, care homes, warehouses and workshops, and the plant rooms serving larger buildings.

Two boundaries catch businesses out. The landlord duty in regulation 36, the one with the 12-month check and the record handed to the tenant, does not reach the commercial side: HSE states that regulation 36 duties do not apply to any gas appliance or installation pipework used exclusively in a part of premises occupied for non-residential purposes. Going the other way, regulation 2(4) puts a list of premises outside most of the regulations altogether, and there the Health and Safety at Work etc Act 1974 and the regulations under it carry the duty instead. HSE says work on gas fittings in those places may be done by a competent person rather than a Gas Safe registered engineer, and that it falls to the employer to check they are competent.

How often is a CP17 needed?

Once a year in practice, though the 12 months comes from the maintenance regime and from contracts rather than from an expiry date on the form. Regulation 35 sets no interval at all: it says maintained in a safe condition and stops there. The interval that does appear in the regulations, at intervals of not more than 12 months, belongs to regulation 36, and that is the landlord duty for let homes. For a workplace, two published sources land on the same answer. HSE says gas appliances and flues should be serviced in accordance with the manufacturer's instructions, and where those are not available recommends they are serviced annually unless the Gas Safe registered engineer advises otherwise. Gas Safe Register's guidance to businesses says one way of meeting the duty is to hold paperwork showing the installation and appliances have been safety checked or serviced at least annually by an appropriately qualified engineer, and that the maximum period between services specified by equipment manufacturers is generally 12 months. Insurers and maintenance contracts then write the same figure into their own terms.

The practical difference from a CP12 is that a CP17 does not expire on a date. It goes stale. A record from 14 months ago is not void, but it has stopped being evidence that the installation is being maintained, which is the question an environmental health officer or an insurer is actually asking. Gas Safe Register is direct about where that leads: if the officer does not receive evidence of ongoing maintenance, or has safety concerns, they may serve a formal notice stating what actions must be taken to comply with the law.

What tests go with a CP17?

A strength and tightness test on the installation pipework, plus a combustion analyser reading, a safety device check, a ventilation check and a flue performance test at each appliance. The tightness test is what changes most between domestic and commercial work, because which IGEM procedure applies is decided by the size and pressure of the installation rather than by the engineer's preference.

Those numbers decide the day. A small cafe on a 32 mm run behind a domestic-sized meter can sit inside IGEM/UP/1B, the same procedure as a house. A pub with a cellar plant room and a kitchen line usually does not, and once the installation volume passes 1 m³ or the pressure passes 40 mbar the work belongs to IGE/UP/1, with the strength test and the purge procedures that go with it. That threshold is also where the engineer's pipework tickets get checked, because testing and purging commercial pipework is a work category of its own. A failed tightness test is not a note in the remedial box either: the unsafe situations procedure treats installations that fail a tightness test as Immediately Dangerous.

Who can issue a CP17?

A Gas Safe registered engineer whose ID card carries the commercial categories for the work in front of them. Commercial competence is a separate lane rather than a senior grade of the domestic one, and an excellent domestic boiler engineer is not registered for a plant room until the commercial tickets are on the card. Gas Safe Register puts it on the customer as well as the engineer: the onus is on you to ensure the engineer is competent to undertake the work you need them to do, and any engineer's categories can be checked on the Register's website or by calling 0800 408 5500. Every registered engineer carries an ID card showing the gas work categories they are registered for and whether their qualifications are current.

Behind those categories sit the ACS assessments an engineer actually books. COCN1, Core Commercial Gas Safety, is the prerequisite for the rest of the commercial sector, and an engineer crossing from domestic sits the changeover core CODNCO1 instead. Appliance and pipework assessments are added on top: CIGA1 for commercial indirect fired appliances, CDGA1 for direct fired air heaters, CORT1 for overhead radiant tube and plaque heaters, ICPN1 for installing commercial pipework over 35 mm, and TPCP1A or TPCP1 for testing and purging it. Catering is a lane of its own again, with its own core and the COMCAT appliance assessments, which is why a restaurant with a boiler and a cooking line often needs two engineers and two records.

How is a CP17 different from a CP12, a CP42 and a CP15?

By what each one covers, not by how serious it is. A CP12 is the domestic landlord record for a let home. A CP17 is an inspection of a workplace's gas installation. A CP42 covers a commercial kitchen's appliances and the environment around them. A CP15 records the commissioning or servicing of a piece of plant rather than an inspection of the whole installation.

The commonest mistake on a commercial site is filing one form and assuming the premises is covered. A pub with a boiler in the cellar and a gas range in the kitchen needs the installation inspected on a CP17 and the catering appliances inspected on a CP42, and those are different competencies on the ID card. A servicing visit on the boiler produces a CP15 and replaces neither.

What happens if a CP17 finds something unsafe?

The engineer classifies it under the Gas Industry Unsafe Situations Procedure, published by IGEM as IGEM/G/11 and currently Edition 2 with amendments dated July 2022, June 2024 and July 2025. There are two classifications and no third. Immediately Dangerous (ID) is an appliance or installation that is an immediate danger to life or property if left connected to the gas supply, and the procedure says these will broadly be installations that fail tightness tests, appliances that fail spillage tests, and appliances with serious flueing, ventilation or combustion deficiencies. At Risk (AR) is a potentially dangerous appliance or installation where one or more faults exist which may in future constitute a danger, and the procedure's own example is inadequate ventilation.

In both cases the engineer explains the finding to the responsible person and, with their agreement, turns the gas off. The procedure even gives the order: the gas isolation valve first, the electrical fuse where that is not possible, and the appliance control as a last resort, with turning down a room thermostat explicitly not acceptable. A “DANGER DO NOT USE” label of at least A7 size goes on the appliance in a prominent position, with a second label on the compartment door where the appliance is concealed. A warning notice is completed and signed by the responsible person as a record of receipt and understanding, and a copy is left with them. On the CP17 itself this shows up in the safety information block, as a Warning/Advice Notice raised and issued and the responsible person notified; the classification lives on the notice.

One clause is specific to commercial premises and worth knowing on both sides of the visit. For non-domestic premises that fall outside the scope of the gas regulations, clause 3.6 says the procedure's safety principles can still be used to classify the risk, that engineers shall consult the responsible person on site, and that the responsible person then exercises professional judgement through risk assessment to determine the safe course of action. Where they want to deviate from the action the procedure advises, they should complete a documented risk assessment. That is a genuine difference from a domestic visit, and it puts the decision, and the paperwork for it, on the business. The procedure also advises keeping records for at least six years in case of future civil litigation, which is a longer horizon than the two years a landlord's CP12 has to be kept.

What does a CP17 cost?

No regulator or trade body publishes a price for the inspection, so this guide does not quote one. The figures on certificate-selling sites are their own rate cards, and they differ mainly in what each seller has decided to include. The only published price that belongs to the CP17 itself is the form: CORGIdirect sells a pad of 50 at £8.00 excluding VAT, checked on 6 September 2026.

What moves a quote is the size of the job. Four appliances fit on one form, so a site with a plant room and a kitchen line runs to several. Which testing standard applies changes the time on site more than anything else. Access to plant, whether anything has to be shut down to test it, and whether the work needs heating and catering categories both move it further. Ask any quote to state how many appliances it covers and which records it produces, because a price for a CP17 on a site that also needs a CP42 is a price for half the premises.

How do you keep a site's CP17 on schedule?

Work from the next-due date held against each site rather than from memory, and keep last year's record where this year's engineer can see it. A lapsed commercial record tends to be discovered by an insurer's renewal questionnaire or an environmental health visit, and by then the conversation is about evidence rather than gas. Engineers who look after commercial clients use Manifold to store each site's reports against the premises, so the previous inspection is on screen during the next one. Keep the renewal date in your own diary as well: Manifold's automatic reminders follow the landlord gas safety record (CP12), not commercial records.