CO certificate (carbon monoxide) for working with gas appliances

Do you perform work on gas combustion installations? For instance, as a central heating engineer? You must have a CO certificate to install, maintain, or repair such equipment. This is stated in the Gas boiler act (Gasketelwet). The CO certificate should reduce the number of accidents with carbon monoxide.

Gas combustion installations are for example:

• central heating boilers
• gas fires and gas stoves
• boilers

When do you need a CO certificate?

You need the CO certificate for installing, repairing, maintaining, and commissioning of a gas combustion installation and the ducts for air supply and flue gas outlet. If you do not have a CO certificate you are not allowed to perform these activities any longer. If you work without a CO certificate, you are liable to prosecution. The consumer commissioning you is also punishable.

Applying for a CO certificate

To obtain a CO certificate for your company, you have to take the following steps:

1. Your central heating engineers who install the equipment must have a Bewijs van Vakmanschap Koolmonoxide (Certificate of Professionalism Carbon Monoxide). To obtain this certificate the installer/engineer must take an exam and/or undergo refresher training with an approved training provider.
2. You must make sure to work according to an evaluation guidline for gas combustion installations, for example InstallQ BRL 6000-25 or KIWA BRL K25000, by an accredited organisation. The guideline lists the requirements, regulations, and laws you must comply with. Describe your working methods in a quality manual. This way, you record your internal procedures and you can demonstrate that you work safely.
3. Apply for CO certification from a certifying body (in Dutch). This certifying organisation checks (audits) whether you work according to the evaluation guideline and whether you meet all requirements to obtain a CO certificate.

Certificate holders register

Does your company have a CO certificate? Then the certifying body will register you in the gas combustion installations register (in Dutch). In this register consumers can look up if your installation company is certified for work on the central heating boiler, gas fireplace or stove, and flue gas outlet. The engineer also needs to show an ID that proves the company is CO certified. This ID may also be digital. And you must use the CO-VRIJ logo (CO-free logo, in Dutch).

If you are not in the register, you are not allowed to work on gas appliances until you obtain the CO certificate.

Reporting (near) accidents involving carbon monoxide

If, during the work, you discover that carbon monoxide is released, this is an accident or near accident. You must decommission the installation and report the accident or near accident to:

• the user and/or owner,
• the municipal authority, and
• the certifying body.