How do you read a CP12?
A CP12, or Landlord Gas Safety Record, lists every appliance and flue with its make, model, type and location, the safety checks done, whether each passed or failed, the check date and next-due date, and the engineer's name, Gas Safe licence number and signature. Check the next-due date first.
Reviewed by Jordan Valentine-Dunn, Gas Safe registered engineer · Portsmouth Gas Heating · Last reviewed July 2026
A CP12, properly called the Landlord Gas Safety Record, can look busy, but it follows a clear layout. It records every gas appliance and flue in the property, the checks carried out on each, the result, and who did the work. Once you know what each part is for, it reads in a couple of minutes.
What does a CP12 record for each appliance?
One row or section per appliance, each telling the same short story: what it is, where it is, what was checked, and how it did. The details are worth knowing because a missing entry is the most common problem a landlord can actually spot.
- For each appliance and flue: the make, model, type and location.
- The safety checks carried out: gas tightness, burner pressure or heat input, flue performance, ventilation, safety devices and physical condition.
- Whether each appliance passed or failed, and any defects found with the work needed to fix them.
- The date of the check and the next check due date.
- The engineer's name, Gas Safe licence number and signature, plus the landlord or agent details and the property address.
What should you check first on a CP12?
Three things, in this order. The next check due date, so you know when the record expires. Whether any appliance is marked as failed or not safe to use, and what the remedial notes say about it. And that every gas appliance in the property is actually listed. That last one matters more than it sounds: the fire in the spare room that predates your ownership still counts, and if it is not on the record, nobody has checked it. If an appliance is missing, ask the engineer why before you file the record away.
What does it mean if an appliance is marked unsafe?
Engineers classify unsafe appliances under the industry's unsafe situations procedure, and the wording on the record follows it. Immediately dangerous means the appliance is a danger to life or property if left connected; the engineer will ask permission to disconnect it and will attach a warning notice. At risk means a fault could become a danger, and the appliance will normally be turned off with the responsible person's agreement. Either way, the record will say what was found and what needs doing. An unsafe classification is not the engineer being awkward; it is the paperwork of a decision made for the people sleeping in the property. Get the remedial work done by a Gas Safe registered engineer, and keep the paperwork for that too.
How do you know a CP12 is genuine?
It should carry the engineer's name, Gas Safe licence number and signature, and that licence number can be checked against the Gas Safe Register online or by asking to see the engineer's ID card. The card shows their photo, their registration number and, on the back, the categories of work they are qualified to do. Only a Gas Safe registered engineer can carry out the check and issue a valid record, so a certificate with no traceable licence number is not worth the paper.
Are digital CP12s laid out the same way?
Yes. There is no single prescribed form, so paper pads and software each arrange the boxes a little differently, but the required content is the same: appliances, checks, results, defects, dates and engineer details. The practical differences favour digital. No carbon-copy handwriting to squint at, nothing faded in a drawer, and the record lands with the landlord the moment the engineer signs it off. Engineers using Manifold complete the CP12 on their phone at the job and the certificate reaches the landlord, and their portal, before the van leaves the street. However it arrives, read it the same way: due date, failures, missing appliances.
Only a Gas Safe registered engineer can carry out the check and judge whether an appliance is safe. This guide helps you read the record; it is not a substitute for the engineer's on-site assessment.
Frequently asked
Sources
Related guides
Last reviewed July 2026. This guide is general information, not legal or safety advice, gas safety work must be carried out by an appropriately Gas Safe registered engineer. Rules can change, so check the linked official sources for the current position.