What are the two types of ceiling radiation dampers used for?

Ceiling radiation dampers play a crucial role in HVAC systems, particularly in fire protection and air management. The correct answer highlights the use of these dampers with return air and supply air diffusers.

When it comes to return air, these dampers are essential in preventing the spread of heat and smoke through the duct system during a fire. They help maintain the integrity of the building’s fire barriers by closing when exposed to heat, thus ensuring that smoke and hot gases do not travel into non-affected areas.

For supply air, ceiling radiation dampers also contribute to the effective distribution of conditioned air while still serving as a fire safety mechanism. They allow air to flow into the space under normal conditions, but if a fire is detected, they can seal off the ductwork to prevent heated air from entering the area.

This dual functionality not only optimizes the efficiency of HVAC systems in regular operations but also enhances safety during emergencies, making the combination of return air and supply air diffusers a vital application for ceiling radiation dampers.

Other options such as exhaust air, intake air only, and supply air only do not fully encompass the dampers' role in fire protection and air flow management.