{"data":{"id":"us/46-cfr-108.409","jurisdiction":"us","citation":"46 CFR 108.409","heading":"Location and spacing of tubing in pneumatic fire detection system.","body":"(a) 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—\n(1) No portion of the overhead is more than 3.6 meters (12 feet) from the nearest point of tubing;\n(2) Beams or girders extending below the ceiling or other obstructions do not detract from the effectiveness of the tubing; and\n(3) Damage to the tubing, is unlikely to occur if it is not protected.\n(b) 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.\n(c) 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.","path":["Title 46—Shipping","CHAPTER I—COAST GUARD, DEPARTMENT OF HOMELAND SECURITY","SUBCHAPTER I-A—MOBILE OFFSHORE DRILLING UNITS","PART 108—DESIGN AND EQUIPMENT","Subpart D—Fire Extinguishing Systems"],"source_url":"https://www.ecfr.gov/api/versioner/v1/full/2026-08-25/title-46.xml","current_through":"2026-08-25","vintage":"","retrieved_at":"2026-08-27T02:26:22Z","sha256":"fb585bb5d8b19a2e3426ada482f8c55eb7c9342000c8b8a6544a8b865f570758","source_id":"us-cfr","stale":true,"prev":"us/46-cfr-108.407","next":"us/46-cfr-108.411"},"notice":"GroundRules: Original legal text. Not legal advice."}