Code Approval of Composite Propane Cylinders for Indoor Use ...

The cylinder breached before the hose stream impact. However, the hose stream impact did notcause additional damage to the cylinder.Key FindingsThe key findings of this research investigation are summarized below.Fire Hazard from Empty or Filled Stored Cylinder1. The maximum heat release rates from the ignition and burning of the empty cylinderswere approximately 100 to 120 kW.2. There was pooling and burning of melted resin. The pool was approximately 3 ft 2 and1 ft 2 for Designs 1 and 2 respectively.3. A full stored cylinder sustained a 300 kW room fire for 20 minutes without beingignited or leaking propane (Test Type 4, Design 1).4. A burning, nitrogen pressurized stored cylinder (Test Type 5, Design 1) did notviolently breach or rupture when impacted with a water hose stream after it hadbreached.Contribution of Leaking Gas from an Ignited Ccylinder toFire Hazards in a Room Fire5. In each of the fire tests (Test Type 2), the ignited composite cylinder in the heaterassembly released gas resulting in flashover conditions in the room.6. In a growing room fire that goes to flashover (Test Type 3), the composite cylinderbreached and ignited after the flashover had occurred. Typically, there was a 3 to 5minute lag between room flashover and breach of the cylinder. The leaking gascylinder (only Design 1) did not rupture.7. Once the cylinder started to leak, the release of gas continued during the test. A fullcylinder was emptied approximately 10 to 15 minutes after the maximum pressurewas reached.Rupture Hazard from Propane Filled Cylinder8. Cylinder design may play a role in its fire performance. For example, Design 2 (twopiecedesign) ruptured when partially filled and in oriented horizontally during a TestType 2 test.9. None of the Design 1 cylinders ruptured during testing.High Velocity Jetting of Propane Gas Flames upon Leakage from the Cylinder10. In all the tests in Test Type 2 and 3, there was no evidence of high velocity jetting ofpropane gas after the composite cylinder had breached and ignited. In tests withpressure relief valves, the cylinder pressure when the breach was observed (128-270psig), was lower than the relief valve setting (375 psig).Composite Propane Cylinders 41February 2007for Indoor Use — Phase IIBattelle