b. The bottom of the 90° elbow must be at least 3 feet (0.9 meters) above the roof deck (or
higher if at risk of being blocked by drifting snow, sand, etc.)
c. The outlet must be covered with a 0.5 inch (12.7 mm) square screen mesh
d. The exhaust vent must be included in the pressure drop calculation
3. For a sidewall exit:
a. You can use an exhaust vent with a 45° elbow (with a deflector rated for the helium
reaction force), a 90° elbow, or vent cap with no restriction in gas flow
b. The exhaust exit must be at least 12 feet (3.66 meters) above the ground
c. The outlet must be covered with a 0.5 inch (12.7 mm) square screen mesh
d. The vent exit must be covered to prevent foreign material from entering or blocking the
opening (e.g., louvers, etc.)
e. The exhaust vent exit must be included in the pressure drop calculation
Illustration 3-19: Cryogenic Exterior Venting Volume
SIGNA Voyager Pre-Installation
Direction 5680008–1EN, Revision 2
92
8 Magnet Room Venting Requirements