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EFFECTIVITY:
C I R R U S
A I R P L A N E M A I N T E N A N C E M A N U A L
M O D E L S R 2 0
15 Jun 2010
B. Repair Environment
The environment required for repairs depends upon the specific repair being made. A cosmetic repair
can usually be made in an uncontrolled environment while more stringent conditions are required for
minor and major repairs.
Heating, ventilating, and air conditioning are among the most important systems of the composite
repair environment. Since repair processes involve the use of resins, adhesives and solvents, it is
important that the work area has adequate ventilation to ensure a safe environment. Humidity and
temperature control is also necessary to ensure the integrity of any repair carried out. Temperature
and humidity recording equipment should be located in the area so that environmental conditions can
be routinely checked.
Guidelines for a proper composite repair environment are:
•
The area must be completely enclosed.
•
Temperature and humidity must be controlled so that the minimum temperature is 60° F (16° C)
with a corresponding relative humidity not greater than 71 percent and the maximum temperature
is 75° F (24° C) with a corresponding relative humidity not greater than 46 percent.
•
The area where surface cleaning of the laminates is done should be isolated from operations that
generate dust, oil vapors, or other contaminants.
•
The operation of fume-producing equipment and fuel-powered combustion engines should not be
allowed. Battery-powered equipment is permitted.
•
Machining or other dust-producing processes should not be allowed in the repair area once the
repair of the damaged structure has been initiated.
•
Protect all surrounding structures that may come in contact with adhesive prior to application pro-
cedures.
•
Material specification must be referenced for specific adhesive application requirements.
•
Composite parts must be handled with clean and powder free gloves prior to bonding.
•
Discarded composite material is to be placed in an appropriate wrapping (e.g. polyethylene bag)
and disposed of as industrial waste. Composite material must not be disposed of by incineration.