Breather valves have the following functions:
Protect tanks
Adjust tank pressure
Prevent excessive pressure differentials
Provide sufficient air to the storage tank
Retain toxic vapors
Prevent atmospheric contamination
Breather valves are attached to a nozzle opening on top of a fixed roof storage tank. They come in different types, including:
Vacuum only
Pressure only
Combined pressure/vacuum
When buying a breather valve, you can consider the following: Price, Line size