§108.409. Location and spacing of tubing in pneumatic fire detection system.
46 C.F.R. § 108.409
All tubing in a pneumatic fire detection system must be on the overhead or within 300 millimeters (12 inches) of the overhead on a bulkhead in a location where—
No portion of the overhead is more than 3.6 meters (12 feet) from the nearest point of tubing;
Beams or girders extending below the ceiling or other obstructions do not detract from the effectiveness of the tubing; and
Damage to the tubing, is unlikely to occur if it is not protected.
If tubing in a tubing circuit is installed in an enclosed space, at least 5% of the tubing in the circuit must be exposed in the space, except that at least 7.6 meters (25 feet) of tubing must always be exposed in the space.
A pneumatic fire detection system must be set to activate after approximately a 22 °C. (40 °F.) per minute increase in temperature at the center of the circuit in the system.
Notes, amendments, and revision history
Authority
Authority: 43 U.S.C. 1333; 46 U.S.C. 3102, 3306; DHS Delegation No. 00170.1, Revision No. 01.4.
Source
Source: CGD 73-251, 43 FR 56808, Dec. 4, 1978, unless otherwise noted.