Thermal flame arrestors

Potential problems with thermal flame arrestors include the following ... 

Although the simple hydrogen supply system layout as shown in Fig. 4.14 is operational in a laboratory envirorrment, additional valves are normally used in order to enhance the safety of system operation. This is normally achieved by inclusion of a shut-off valve upstream of the pressure reducer and a pressirre relief valve (safety valve) that will prevent hazardous pressure birild-up in the case of failtue of the pressure reducer (Fig. 4.15). The shut-off valve can be operated manually or as a control valve. Additioiral safety features may include a thermal activated fuse between the storage cylinder and shut off valve, filters, flow restrictors as well as a flame arrestor. 

Flares, thermal oxidizers, and incinerators are open flame devices that may require flame arrestors or other devices to prevent flashback. 

Detonation arrestors are essentially heavy-duty thermal-type flame arrestors designed to handle the peak overpressures of a detonation. These would only be used in those systems where the criteria for distance from the atmospheric outlet... 

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