Fire Exhaust Axial Flow Fans are generally used for fire protection purposes, to exhaust smoke during the early stages of a fire, and are heat-resistant. They are typically designed to operate normally for 30 minutes at a temperature of 280 degrees. Fire Axial Flow Fans include both Exhaust Axial Flow Fans and Supply Axial Flow Fans (which have symmetrical construction), one for exhaust and the other for supply. The Supply Axial Flow Fan is also known as a Fire Make-up Axial Flow Fan in professional terms. Appendix: Working Principle of Axial Flow Fans - Axial Flow Fans have a wide range of applications, where the airflow is in the same direction as the fan's shaft, such as in electric fans and outdoor fans for air conditioners, which operate as axial flow fans. They are called "axial flow" because the gas flows parallel to the fan's axis.