CP1 Certificates ​
A CP1 (Commissioning Proforma 1) is an official document that certifies a gas appliance has been correctly installed, commissioned, and is safe to use.
What is a CP1? ​
The CP1 is a Gas Safe requirement. When an engineer installs a gas appliance (like a boiler), they must complete a CP1 to:
- Confirm the installation meets regulations
- Record technical details of the appliance
- Certify safety checks have been completed
- Provide documentation for the customer and Gas Safe Register
When is a CP1 Required? ​
A CP1 must be completed for:
- New boiler installations
- Boiler replacements
- Any new gas appliance installation
It is not required for:
- Repairs to existing appliances
- Service/maintenance visits
- Non-gas installations (EV chargers, air conditioning)
What's Included in a CP1? ​
The CP1 form captures:
Appliance Details ​
- Manufacturer and model
- Serial number
- GC number (Gas Council number)
- Location in property
Installation Checks ​
- Gas pressure readings
- Flue flow test results
- Ventilation assessment
- Safety device checks
Engineer Details ​
- Gas Safe registration number
- Engineer name and signature
- Date of installation
Customer Details ​
- Customer name
- Property address
- Customer signature confirming handover
CP1 in the App ​
In the Engineer App, the CP1 is completed:
- During the job - Engineer fills in readings and checks as they work
- Photos - Required photos are attached (flue, etc.) in separate photo step of job
- Signatures - Both engineer and customer sign on screen
- Submission - CP1 is submitted with the job completion