TM 9-2330-398-10
1-1. SCOPE (continued).
c. Before loading or unloading fuel or purging tank on semitrailer, connect all bonding and grounding connections
d. Never climb on the semitrailer without first touching a grounding stud to discharge static electricity from your body.
e. Under normal circumstances, perform all maintenance on the semitrailer outdoors, away from buildings, and with
the tank empty The semitrailer tank should be checked to make sure it is free of vapors that could ignite during
maintenance activities.
f. If circumstances require that maintenance be performed inside a building, the semitrailer tank must be thoroughly
drained and purged and the exterior of the semitrailer must be steam cleaned. After purging, the combustible gas
indicator must read in the SAFE zone. Even if the semitrailer has tested SAFE with a combustible gas indicator
set, the semitrailer MUST be retested prior to starting work each day and at regular intervals throughout the day.
This test can be accomplished by authorized Unit or Direct Support maintenance personnel with a military
occupational specialty (MOS) of 77F or the equivalent (see FM 10-20).
g. Hearing protection is required for personnel within 50 feet (15.25 m) of the semitrailer when the pump engine is
running.
h. To reduce the risk of fire and explosion, DO NOT perform the following operations on the semitrailer unless the
tank has been drained and purged and the exterior has been steam cleaned:.
Replace any component that communicated with the inside of the tank and therefore came in contact with
fuel or vapors; these components include the manhole, the jet level sensor and tubing, the emergency valve,
vapor collection system components, vent caps, the sump drain, and the piping assembly.
Troubleshoot the electrical system with any test device other than the ohms scale of a multimeter.
Cut with acetylene torch or chisel and hammer.
Drill (except aluminum).
i. Follow these rules if working inside a purged tank:
Always provide adequate forced air ventilation with air directed inside to the compartment where work is
being performed.
NEVER work alone inside a tank; a second person must be stationed at the manhole opening. A third
person must be close by to provide aid and/or assistance in case of an emergency. The person inside the
tank must have on a safety line and harness for rescue operations in case of emergency.
If the person inside the tank encounters any difficulties, the person stationed at the manhole must summon
assistance IMMEDIATELY. DO NOT attempt a rescue until assistance has arrived.
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