Question

type i - question # 11
after recovering refrigerant from a sealed system, if nitrogen is used to pressurize or blow debris out of the system, the nitrogen;
a must be recovered.
b may be vented to the ambient air.
c should be returned to the cylinder.
d should only be used if mixed with r - 22

Explanation:

Nitrogen is an inert gas and is not a regulated refrigerant. It is safe to vent to the ambient air after use in pressurizing or blowing debris out of a refrigeration - sealed system post - refrigerant recovery.

Answer:

B. may be vented to the ambient air.