301 Emergency Vents
The OPW 301 Emergency Vent is
designed to prevent an aboveground
storage tank from becoming over-pressurized by providing high-capacity
venting in the event of a fire or blockage.
The 301 is a weighted, mushroom-style
emergency vent. When the AST builds
pressure, the weighted cast-iron lid
is forced up off its seat to relieve the
pressure. When pressure is relieved, the
lid lowers and is automatically reset.
The
appropriate 301 Series vent is determined
by the emergency venting capacity
requirements of the AST and the type of
connection at the tank’s emergency vent
opening. The OPW 301 Emergency Vent
is available in 4", 6" and 8" openings
with female NPT, and male NPT to allow
for easy installation in new or existing
aboveground tanks. Various lid-pressure
settings determine the initial venting
of the valve.
