Carbon monoxide is the most common exhaust fume in these types of garages however there is also the possibility for nitrogen dioxide from diesel powered engines and hydrogen buildup from electric car charging stations. Another issue can be combustible gas. Radiant heaters are often found in warehouses. They typically are powered by some type of combustible gas. This situation is common throughout the year, but especially dangerous in the winter months when doors and ventilation system dampers are kept closed. Within seconds, gas levels can rise to more than 10 times the permissible exposure levels (PEL’s) and within minutes be easily at or over immediately dangerous to like and health (IDLH) levels. A gas detection system is necessary to provide a safe environment in the warehouse as well as minimizing the energy costs related to the operation of the ventilation system. It is not practical or environmentally friendly to run the exhaust/supply fans continuously, as wear and tear drastically shortens the life expectancy of the equipment resulting in higher maintenance fees and services.