NOTE: This is an unformatted excerpt from our online fire protection training library.
Zone Classification
Exceptions
A conduit that passes completely through a classified area with no fittings, including threaded couplings, less than 12 inches from the boundary is not required to be sealed. This assumes that the conduit terminations are not in other classified areas. The exception recognizes that gas or vapor will not be able to enter through the wall of an unbroken conduit and no sources of ignition will be present, so seals will not be needed to minimize gas or vapor flow or halt flames.
© Hughes Associates,Inc. 2012
NOTE: This is an unformatted excerpt from our online fire protection training library.