General questions Flashcards
MN Test
What is the minimum operating pressure for sprinkler heads?
7 PSI
A PRV is set to what pressure?
175 PSI
What is the minimum discharge of a residential sprinkler head?
18 gpm
What distance should a hose valve be off of the floor?
3 to 5ft
Distance the FDC should be off the ground?
18 in to 48 in
What is the Minnesota State Fire Code
299M
What is the max zone square footage for extra hazard occupancy?
25,000 square ft
What is the max distance between hangers for 1 in sch 40 pipe?
12 ft
Who invented pipe calculations?
Hazen Williams
How much weight should a single hanger support?
Five times the weight of water filled pipe plus 250 pounds.
How many gauges are on a dry system?
2
What is the pitch of pipe on a dry system?
1/2” per 10ft on branch lines
1/4 per 10ft on mains
How many heads do you calculate on an NFPA 13R system?
4
What is the Maximum time for a compressor to fill a dry system?
30 minutes
Post indicating valves should be at least how many feet away from a building?
40 ft