What must be checked during the oven testing procedure after 5 minutes of operation?

During the oven testing procedure, checking the steady state carbon monoxide (CO) levels after 5 minutes of operation is essential for ensuring the safety of the appliance. This is because carbon monoxide is a colorless, odorless gas that can be produced during combustion processes in gas appliances. By measuring the CO levels, you are assessing whether the oven is functioning correctly and if it is operating within safe limits. It helps to confirm that there is proper ventilation, and that the combustion process is complete, which minimizes the risk of CO leakage into the living space. Maintaining safety standards in gas appliances is crucial to prevent poisoning and ensure user safety.

While other aspects such as ambient temperature, oven light functionality, and baking temperature may be important for the overall functioning and convenience of the oven, the immediate safety concern lies with the carbon monoxide levels, which directly relate to the combustion process of the appliance.