Technical data

b. Electrostatic coating application equipment shall be
used only in paint hangars or other areas designated and
approved by the local base Fire, Safety, Bioenvironmen-
tal, and Environmental Office.
c. The ventilation system is on and operating and must also
provide sufficient exhaust to remove the solvent vapors
generated by the process. The ventilation shall be
sufficient to limit vapor concentration to 500 part per
million or 20 percent of the LEL, whichever is lower as
defined in OSHA Standard 1910.94. Electrostatic paint-
ing equipment powered by an external electrical source
requires an interlock system to ensure that equipment
can only be operated if the ventilation system is opera-
tional. An interlock system is not required for pneumati-
cally operated equipment; however, the paint hangar
facility shall be equipped with an audible alarm system
which activates in the event of a ventilation system
failure.
d. All painters using the electrostatic equipment shall be
trained in its use, the hazards associated with electro-
static painting, and the fire/safety problems associated
with the process.
e. All safety and regulating features on all equipment are
operational.
f. No unauthorized personnel are allowed in the paint
hanger during electrostatic painting operations.
g. Any personnel involved in concurrent operation in the
paint hangar, not associated with the electrostatic paint-
ing process shall be briefed on the hazards of static on
ungrounded objects and provided the appropriate safe-
guards.
h. All aircraft, the electrostatic equipment, work stands,
solvent containers/buckets, people, and adjacent equip-
ment shall be grounded prior to using the electrostatic
painting equipment.
i. Prior to cleaning electrostatic paint guns, the operators
shall ensure that they and the gun are grounded, and that
the equipment is de-energized.
j. The manufacturer’s operational/safety procedures are
used to supplement these procedures.
k. All electrical equipment within the paint hangar facility
must be approved for explosion-proof environments.
The electrostatic painting equipment used for this pro-
cess must have been tested and approved by a recog-
nized laboratory for Class I, Division I, Groups C and D
locations.
l. When painting aircraft fueled with JP-5, and JP-8, the
paint hangar facility and aircraft shall be protected by a
fire suppression system. The fire suppression system
must be fully operational prior to the start of electro-
static painting. Facility fire suppression required for
electrostatic painting of fueled aircraft is outlined in
MIL-STD-3007, ETL 02-15, and ETL 98-8.
m. Supervisory personnel must ensure all fire/safety coun-
termeasures have been implemented prior to the start of
the painting operation.
n. LEL readings in the fuel vent area must be taken prior to
the painting of each aircraft. LEL readings must be
maintained at or below 20 percent.
5.5.4 Atmospheric Conditions For Painting. Nor-
mally, coatings should not be applied under unfavorable
atmospheric conditions such as high humidity, strong drafts
or extremes of temperature. Painting should be accomplished
whenever possible in an environmentally controlled facility
capable of maintaining a range of 30 to 80 percent relative
humidity and 60° F to 90° F. Some coatings may be applied
outside these ranges without significant adverse effects, but
paint personnel should always watch for adverse effects when
applying paint outside of these ranges and develop painting
decisions based upon local experiences for the particular
types of coatings used and the local climate. Factors to be
considered are:
5.5.4.1 The temperature of surfaces being painted should
be considered in any painting decision since it is a major
factor in the drying or cure of coatings.
5.5.4.2 Low humidity retards the cure of moisture curing
coatings.
5.5.4.3 High humidity can cause blushing of lacquers and
also may result in condensation on the coating if the tem-
perature of the coating drops to the dew point.
5.5.4.4 Low temperatures cause slow drying, or cure,
longer tack time, and sometimes incomplete cure. If the
temperature is 50° F or lower, painting operations should be
suspended.
5.5.4.5 High temperatures cause too rapid an evaporation
of solvent which leads to premature skinning, pinholes or
solvent pop, blisters, cracked finish, or excessive dry spray. If
the temperature exceeds 95° F, painting operations should be
suspended.
TO 1-1-8
5-6 Change 3