What a Gas Safety Record Actually Is
A gas safety record, widely known as a CP12 (the old CORGI form number that has stuck in common usage), is the formal written record produced after a gas safety check on a gas appliance and installation at a rented property. It is not the same as a service report, a boiler commissioning sheet, or a building control certificate. It is a specific document produced under Regulation 36 of the Gas Safety (Installation and Use) Regulations 1998, and its content, retention, and distribution are all prescribed by law.
The check itself covers every gas appliance and flue in a property. The engineer assesses whether each appliance is safe, whether the flue is functioning correctly, whether there is adequate ventilation, and whether the operating pressure and heat input are correct. The record then documents the outcome of each check, any defects identified, any remedial action taken, and whether the appliance has been left safe to use or has been turned off and labelled 'Immediately Dangerous' or 'At Risk'.
It is worth being clear on what the CP12 is not. It is not proof that a boiler has been serviced. A service and a safety check overlap, but they are distinct activities. A boiler can receive a full service without a formal Regulation 36 check being completed, and vice versa. If a landlord needs a gas safety record for their tenancy, a service invoice alone does not satisfy the legal requirement.
- •Governed by Regulation 36, Gas Safety (Installation and Use) Regulations 1998
- •Required for every gas appliance and flue in a rented residential or commercial property
- •Must document each appliance checked, the result, any defects, and the safety status
- •Distinct from a boiler service, a commissioning certificate, or a general inspection report
- •Commonly called a CP12, though that label dates from CORGI registration, which ended in 2009
Who Must Issue a Gas Safety Record and Who Can Legally Do the Check
Only a Gas Safe registered engineer can legally carry out a gas safety check and issue a gas safety record in the UK. This is not a matter of best practice. Regulation 3 of the Gas Safety (Installation and Use) Regulations 1998 makes it a criminal offence for anyone who is not on the Gas Safe Register to carry out gas work, including the checks that underpin a Regulation 36 record. As a sole trader, your individual Gas Safe registration number must appear on the completed record, along with your name and the date of issue.
The obligation to arrange and obtain the record sits with the landlord, not the engineer. Under Regulation 36(3), the landlord of any domestic premises let under a relevant tenancy must ensure a gas safety check is carried out at intervals of no more than 12 months and that a record is obtained. The engineer's obligations are to carry out the check competently and to complete the record accurately. If the landlord fails to arrange the check, the landlord commits the offence. If the engineer falsifies a record or completes it negligently, the engineer faces separate enforcement action.
For sole traders this distinction matters in practice. Your job is to carry out the check properly, record the findings honestly, and issue the document on the day. You are not responsible for the landlord's failure to book the annual check on time, but you are responsible for the accuracy and completeness of every record you sign. Gas Safe can and does audit records as part of its inspection regime, and an inaccurate record can lead to suspension or removal from the register.
- •Only Gas Safe registered engineers can legally perform the check and issue the record
- •Your individual Gas Safe registration number must appear on the completed document
- •The landlord holds the legal duty to arrange annual checks under Regulation 36(3)
- •The engineer holds the legal duty to carry out the check competently and record findings accurately
- •Gas Safe inspectors can request copies of your records during routine audits
When a Gas Safety Record Is Required
The trigger for a mandatory gas safety record is straightforward: any residential premises let under a relevant tenancy, as defined in Regulation 36 of the 1998 Regulations, must have gas appliances checked annually. The 12-month clock runs from the date of the previous check, not from the tenancy start date. If the previous check was carried out on 14 March 2025, the next one must be completed by 13 March 2026. Many landlords do not understand this and book the check around tenancy renewal dates instead, which can leave them outside the 12-month window.
There is a grace arrangement that allows checks to be carried out up to two months before the expiry date without resetting the anniversary. So if the current record expires on 13 March 2026 and the check is done on 20 January 2026, the next record is still valid until 13 March 2027, not 20 January 2027. This is worth explaining to landlords you work with regularly, as it lets them plan appointments in advance without losing months off the certificate period.
Gas safety records are not required by regulation for owner-occupied properties. A homeowner commissioning a gas safety check receives a service report or safety inspection notice, but there is no statutory obligation on the engineer to produce a Regulation 36 record in that context. However, many engineers choose to produce a CP12-style document for owner-occupiers as good practice and as a record for their own files. This is perfectly acceptable as long as the document is clearly labelled and not confused with a statutory landlord record.
- •Required annually for every gas appliance in any premises let under a relevant tenancy
- •The 12-month period runs from the date of the last check, not the tenancy anniversary
- •Checks can be booked up to 2 months early without shortening the next certificate period
- •Not a statutory requirement for owner-occupied properties, though good practice to document
- •Commercial landlords and housing associations are also subject to Regulation 36 duties
What the Gas Safety Record Must Contain
Regulation 36(3)(b) of the Gas Safety (Installation and Use) Regulations 1998 sets out the mandatory content of a gas safety record. Getting this right on every job is not just about legal compliance. A record with missing fields can be challenged as invalid, which leaves the landlord technically non-compliant even though they paid for and received a document.
The required fields are: the date the check was carried out; the address of the premises; the name and address of the landlord (or their agent); a description of and the location of each appliance or flue that was checked; the signature and Gas Safe registration number of the engineer; and the results of the checks, including any defects identified and any action taken. In practice, most printed and digital CP12 templates include space for the appliance make and model, the operating pressure, heat input readings, and the flue flow test result, which are all things Gas Safe expects to see if a record is audited.
A common mistake sole traders make is leaving the landlord name and address blank when they are working for a letting agent rather than dealing with the landlord directly. The Regulation requires the landlord's details, not the agent's. If you are booking through an agent, ask for the landlord's name and address before the job. If the agent refuses to provide it, that is their legal problem, but you should flag it in writing and keep a copy.
- •Date of the check
- •Address of the premises inspected
- •Name and address of the landlord or their authorised agent
- •Description and location of each appliance and flue checked
- •Results of each check, any defects found, and any remedial action taken
- •Engineer's name, signature, and Gas Safe registration number
- •Safety status of each appliance: Safe, Immediately Dangerous (ID), or At Risk (AR)
The Law Behind It: Regulation 36 Explained
The Gas Safety (Installation and Use) Regulations 1998 are the primary legal instrument governing gas safety checks and records in the UK. They were made under the Health and Safety at Work etc. Act 1974, which means enforcement sits with the Health and Safety Executive rather than local trading standards or planning authorities. Regulation 36 is the specific provision that creates the landlord's annual duty and sets out the record requirements.
Regulation 36(6) requires the landlord to give a copy of the current gas safety record to each existing tenant within 28 days of the check being completed, and to any new tenant before they move in. This is often where landlords fall down. The engineer issues the record on the day of the visit. The landlord then has a 28-day window to pass it to the tenant. If the landlord delays or forgets, they are in breach of Regulation 36(6), not the engineer. That said, if you are managing the process on behalf of a landlord client, it is worth building a reminder into your workflow.
The Health and Safety at Work etc. Act 1974 also creates broader duties that apply to gas engineers as sole traders. Section 3 of the 1974 Act imposes a duty on self-employed persons to conduct their undertaking in such a way as to ensure, so far as is reasonably practicable, that persons not in their employment who may be affected are not exposed to risks to their health or safety. An engineer who completes a gas safety record negligently, missing a dangerous appliance or falsely recording it as safe, is potentially in breach of section 3 as well as Regulation 36.
- •Gas Safety (Installation and Use) Regulations 1998, Regulation 36: the primary duty and record requirements
- •Regulation 36(6): landlord must give a copy to existing tenants within 28 days and to new tenants before move-in
- •Health and Safety at Work etc. Act 1974, section 3: self-employed engineers' duty to protect third parties
- •HSE is the enforcing authority, not local councils or trading standards
- •Records must be retained by the landlord for at least 2 years from the date of the check
How Long a Gas Safety Record Lasts
A gas safety record is valid for 12 months from the date the check was carried out. After that date, the landlord is non-compliant and the property is effectively without a valid record until a new check is done. There is no grace period after expiry. A landlord cannot legally let a property without a valid gas safety record in place, and if an accident occurs after expiry, the absence of a valid record will be a significant factor in any HSE investigation or civil claim.
The engineer's copy of the record, along with supporting notes and readings, should be retained in your own files for a minimum of two years. Many experienced engineers keep records for longer, particularly for jobs where an appliance was classified as Immediately Dangerous or At Risk. If a fault later leads to an incident and there is a question about what you found and what you told the customer, your copy of the record is your primary defence.
Records must also be legible and reproducible. If you complete records digitally, make sure the stored copy can be printed or shared in a format that HSE inspectors or a court would accept. A blurry photograph of a handwritten form stored on a phone that has since been lost is not adequate record-keeping.
- •Valid for exactly 12 months from the date of the check
- •No grace period applies after expiry: the landlord is non-compliant from the expiry date
- •Landlords must retain records for at least 2 years
- •Engineers should retain their copies for at least 2 years, and longer for any ID or AR findings
- •Records must be legible and retrievable in a format acceptable to HSE
Penalties for Non-Compliance: Real Figures
Non-compliance with Regulation 36 is a criminal offence under the Gas Safety (Installation and Use) Regulations 1998. The penalties available to HSE under the Health and Safety at Work etc. Act 1974 include unlimited fines on conviction in the Crown Court, and fines of up to £20,000 in the Magistrates' Court. Custodial sentences of up to two years are also available for the most serious cases. HSE prosecutes landlords for missing or out-of-date gas safety records every year, and the fines in the reported cases typically range from £1,500 to £15,000 for a first offence, rising steeply where there is a history of non-compliance or where a tenant was put at risk.
For engineers, the consequences of producing an inaccurate or falsified record go beyond HSE enforcement. Gas Safe can remove an engineer from the register following a misconduct investigation. Removal from the register ends your ability to work legally as a gas engineer in the UK, which for a sole trader is effectively the end of the business. Gas Safe's investigation process is separate from HSE's, so it is possible to face both a criminal prosecution and a Gas Safe misconduct finding from the same incident.
Landlords who let a property without a valid gas safety record can also face consequences through the Housing Act 2004 and the Homes (Fitness for Human Habitation) Act 2018, as the absence of a safety record can be used to support a finding that the property is unfit. In the private rented sector, a landlord who has not served a valid gas safety record on a tenant cannot serve a Section 21 notice to evict that tenant under the Deregulation Act 2015. This is not directly an engineer's concern, but landlords who understand this consequence tend to take the annual check deadline seriously, which makes your job of arranging access easier.
- •Unlimited fine in Crown Court for Regulation 36 offences under the Health and Safety at Work etc. Act 1974
- •Up to £20,000 fine in the Magistrates' Court
- •Up to 2 years' custodial sentence for the most serious cases
- •Reported landlord fines typically range from £1,500 to £15,000 for a first offence
- •Engineers face Gas Safe misconduct proceedings independently of any HSE criminal action
- •Landlords without a valid record cannot serve a Section 21 eviction notice under the Deregulation Act 2015
A Worked Real-World Example
Here is a scenario that plays out regularly across the UK. Mohammed is a sole-trader gas engineer, Gas Safe registered, working across a portfolio of 15 properties managed by a letting agent in the East Midlands. On 4 February 2026 he carries out a gas safety check at a two-bedroom terraced house in Nottingham. He finds the boiler operating correctly, the flue in good condition, and the gas fire in the living room showing signs of incomplete combustion with a cracked ceramic. He classifies the gas fire as Immediately Dangerous, turns it off, labels it, and explains the situation to the tenant.
Mohammed completes the CP12 record on the same day. He records the boiler as safe, the gas fire as Immediately Dangerous, the action taken (isolated at the appliance valve and labelled), and the advice given to the tenant (not to use the fire until repaired by a Gas Safe engineer). He signs the record, notes his Gas Safe registration number, and uploads it to his job management system. He emails a copy to the letting agent and keeps a copy in his own records. The gas safety record is valid from 4 February 2026 to 3 February 2027.
The letting agent forwards the record to the landlord, who sends a copy to the tenant by email on 20 February 2026, which is 16 days after the check and within the 28-day requirement under Regulation 36(6). The landlord arranges repair of the gas fire in March 2026. Mohammed returns to test and verify the repair and issues a separate repair notice. The next annual check must be booked by 3 February 2027. If Mohammed books it in December 2026, the new record will still carry a 12-month period running to 3 February 2028, because the early-booking rule allows checks up to two months before expiry without resetting the clock.
- •Job date: 4 February 2026
- •Record valid until: 3 February 2027
- •Boiler: Safe. Gas fire: Immediately Dangerous (isolated and labelled on the day)
- •Record issued to tenant by landlord on 20 February 2026 (within the 28-day window)
- •Early re-book by December 2026 keeps the 12-month anniversary intact
- •Mohammed retains his copy and all supporting readings for at least 2 years
What Changes in 2026 That Gas Engineers Need to Know
For most CP12 work, the core rules under Regulation 36 of the Gas Safety (Installation and Use) Regulations 1998 are unchanged in 2026. However, if your work includes gas tightness testing as part of a broader installation or recommissioning job, there is a significant technical change coming from 1 October 2026. IGEM/UP/1B Edition 4 comes into force on that date and changes how permissible pressure drops during tightness testing are determined.
Under Edition 4, the permissible pressure drop in a gas installation during a tightness test is no longer determined by the meter size. It is now determined by the Installation Volume. Any perceptible movement on a gauge can no longer be attributed to the installation pipework under the new methodology. This affects how you conduct, record, and interpret tightness tests on larger or more complex installations, and it will change the pass/fail threshold in some scenarios compared to what engineers have been using under the previous edition.
If you carry out gas tightness tests as part of your work, you should familiarise yourself with IGEM/UP/1B Edition 4 before October 2026. Gas Safe has indicated it expects registered engineers to be working to the current edition of IGEM standards, and auditors will be looking for compliance with Edition 4 in records dated after 1 October 2026. For routine CP12 safety checks on domestic appliances without installation work, the day-to-day process remains the same.
- •IGEM/UP/1B Edition 4 effective 1 October 2026: tightness test permissible pressure drop now based on Installation Volume, not meter size
- •Any perceptible gauge movement can no longer be attributed to installation pipework under Edition 4
- •Affects engineers doing installation or recommissioning work, not routine annual safety checks
- •Gas Safe auditors will expect Edition 4 compliance on records dated after 1 October 2026
- •Routine domestic CP12 checks on existing appliances are not affected by this change
Common Mistakes Sole Traders Make on Gas Safety Records
The most frequent errors found when Gas Safe audits records are incomplete mandatory fields, particularly missing landlord details, and appliance descriptions that are too vague to be useful. Writing 'boiler checked, OK' is not a record. You need the make and model, the location, the operating pressure, the heat input, the flue flow test result, and the safety status. If Gas Safe asked you to explain your findings for that appliance three years later, your record needs to be detailed enough to reconstruct the visit.
A second common error is issuing a record where an appliance has been classified as Immediately Dangerous but the record does not clearly document that the appliance was isolated before the engineer left the property. The whole point of the ID classification is to protect the occupant. If your record says 'ID' but does not confirm isolation, you are leaving yourself exposed if there is a later incident. Always record the action taken, not just the classification.
A third issue is engineers completing records for properties where the gas meter is not in their name and the property status is unclear. If you are uncertain whether a property is rented or owner-occupied, ask. Issuing a Regulation 36 record for an owner-occupier when they have not requested one is not harmful in itself, but it creates a false impression of what the document is and can cause confusion if the property is later sold or let. Keep your records accurate to the actual status of the property.
- •Incomplete mandatory fields, especially landlord name and address
- •Vague appliance descriptions without make, model, pressure readings, or heat input
- •ID classification without confirming isolation action in the record
- •Failing to note that the tenant was informed of any ID or AR finding
- •Issuing a record without signing it or noting your Gas Safe registration number
- •Storing only a paper copy with no backup, which can be lost or destroyed
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