What is the first step you should take if refrigerant is leaking in a closed environment?

In the event of a refrigerant leak in a closed environment, the immediate priority is to ensure the safety of all individuals present. Vacating and ventilating the area is crucial because refrigerants can be harmful or even fatal in high concentrations. Evacuating the space reduces the risk of exposure to potentially toxic fumes, while ventilating helps to disperse the refrigerant, ensuring that the environment is safer for both the personnel and any potential responders.

This step prioritizes human safety by removing people from a hazardous situation and allowing fresh air to enter the environment. Addressing the leak source and turning off power to the system can only follow once it is safe to do so. Sealing windows and doors would restrict ventilation, which is counterproductive in this scenario and could increase the risk associated with the leak. Therefore, the first and most important step is to vacate and ventilate the area to mitigate any immediate dangers posed by the refrigerant leak.