3.3.3
Primer and Bond Breaker
Install the type recommended by the sealant manufacturer.
3.3.4
Ambient Temperature
Between 4 degrees C 38 degrees F and 35 degrees C 95 degrees F when
applying sealant.
3.3.5
Exterior Sealant
For joints in vertical surfaces, provide ASTM C 920, Type S or M, Grade NS,
Class 25, Use NT. For joints in horizontal surfaces, provide ASTM C 920,
Type S or M, Grade P, Class 25, Use T. Color(s) shall be selected by the
Contracting Officer. Apply the sealant in accordance with the
manufacturer's printed instructions. Force sealant into joints with
sufficient pressure to fill the joints solidly. Sealant shall be uniformly
smooth and free of wrinkles.
3.3.6
Cleaning
Immediately remove fresh sealant from adjacent areas using a solvent
recommended by the sealant manufacturer. Upon completion of sealant
application, remove remaining smears and stains and leave the work in a
clean condition. Allow sealant time to cure, in accordance with
manufacturer's recommendations, prior to coating.
]3.4
SURFACE PREPARATION
**************************************************************************
NOTE: Existing coating systems need to be defined
compositionally before recoating:
1. Hazardous Materials:
When planning either
partial or full removal of existing coatings,
regulatory restrictions and procedures shall be
followed. Records establishing the composition of
materials in the coating systems, if available, may
assist in a preliminary review of planned surface
preparation and disposal. Generally an overall
assessment of applicable regulations for personnel
and environmental protection will be required, with
appropriate sampling and testing, followed by use of
proper material control procedures.
2. Compatibility of the existing coating system
with a planned repair or overcoating system should
be determined by procedures such as the following:
a. Identification of the existing topcoat and any
undercoats that will be exposed, by consulting local
records.
b. If binder extraction is possible, ASTM D 2621,
"Infrared Identification of Vehicle Solids from
Solvent-Reducible Paints," can be used for vehicle
identification.
c.
General compatibility considerations and chart
SECTION 09900
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