[F] 413.9.2 Atmospheric Venting
The structure or appurtenance used for stabilizing the cylinder shall be separated from the site equipment, features and exposures and shall be located in accordance with Table 4126.96.36.199.
[F] TABLE 4188.8.131.52
SEPARATION DISTANCE FOR ATMOSPHERIC VENTING OF CNG
|EQUIPMENT OR FEATURE||MINIMUM |
|CNG compressor and storage vessels||25|
For SI: 1 foot = 304.8 mm.
A vent tube that will divert the gas flow to the atmosphere shall be installed on the cylinder prior to the commencement of the venting and purging operation. The vent tube shall be constructed of pipe or tubing materials approved for use with CNG in accordance with the International Fire Code.
The vent tube shall be capable of dispersing the gas not less than 10 feet (3048 mm) above grade level. The vent tube shall not be provided with a rain cap or other feature that would limit or obstruct the gas flow.
At the connection fitting of the vent tube and the CNG cylinder, a listed bidirectional detonation flame arrester shall be provided.