What is the first step to achieve the CAZ baseline configuration?

To achieve the CAZ (Combustion Appliance Zone) baseline configuration, closing all exterior doors and windows is an essential first step. This action helps to establish a controlled environment that accurately reflects the air pressure and ventilation conditions present within the space where the combustion appliances operate.

By closing all external openings, you prevent outside air from infiltrating, which could disrupt the integrity of the pressure measurements and airflow dynamics essential for testing. This setup allows for a more precise assessment of how the appliance interacts with the environment and ensures that the subsequent measurements and evaluations of combustion safety are reliable.

The other options may not contribute to establishing a consistent and controlled environment necessary for the baseline configuration. For example, opening all windows and doors would introduce variables that could affect the airflow and pressure readings. Setting appliances to maximum settings or turning them off may not accurately represent typical operational conditions needed to gauge safety parameters effectively.