Exhaust fan

The magnet (RF-shielded) room exhaust fan, vent, and duct system are intended to evacuate the magnet room of cryogenic gas at the MR product specified rate. Over time, the exhaust fan system may become blocked with lint, hair, and other air-borne particles. It is important for personnel safety reasons that the exhaust fan system (vent, exhaust fan, ducts, etc.) be kept clean to make sure the exhaust fan system operates properly and exhausts cryogenic gas to an outside area.

In the unlikely event of a magnet quench or a cryogen gas leak, it is important that this exhaust fan system performs at or above the specified airflow to remove the cryogen gas from the magnet room. The magnet room exhaust fan and air inlet must be sized for a minimum of 1200 CFM (34 m3/minute) and minimum of room 12 air exchanges per hour. The minimum air flow and air exchange rate for mobile, transportable, and relocatable systems are different from those for fixed sites and varies depending on the type of site. Any blockage or obstruction could prevent the exhaust fan system from providing the required airflow. If the exhaust fan system fails to operate at or above specification, accumulation of dangerous levels of helium or nitrogen within the RF screen room could occur.

It is important that this exhaust system vent be cleaned regularly as part of the normal room cleaning. Regular customer inspection, cleaning, and testing of the exhaust fan system (vent, exhaust fan, ducts, etc.) are needed to make sure all equipment and parts of the system are always in good working order and able to perform to specification. It is recommended the exhaust fan system be cleaned and inspected annually to make sure the specified air flow rate can be met and thus ensures proper performance.