TM 9-4940-444-14 & P
EXHAUST PIPING INSTRUCTIONS - cont.
L. Location of Piping.
1. Location:
Header pipe should be located above the equipment exhausted whenever possible and supported from ceiling or
roof above.
2. Clearance:
All piping shall be kept at least 6" away from combustible parts of the building structure.
3. Fire Walls:
Pipe systems should not extend through fire walls unless necessary and in such cases, fusible link pipe shutters
shall be provided on each side of the fire wall - preferably of the verticle type described in the code of the National
Fire Protection Association on blower systems.
M. Fire and Explosion Hazards.
1. Electrical Ground:
Any exhaust system handling matter of an explosive nature shall have the piping and other equipment
permanently grounded through electrical conductors.
2. Non-Ferrous Construction:
Exhaust systems handling highly flammable or explosive matter shall have such parts of the system, that are
exposed to being hit be metallic objects, made from non-ferrous materials to prevent the possibility of sparks.
Fan impellers in such installations shall be made entirely of non-ferrous material and in extremely hazardous
operation the fan housing shall be constructed of non-ferrous material. in all other respects, the system shall meet
the minimum requirements of the code on blower systems prepared by the National Fire Protection assoc.
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