insulating cement and cloth is an impractical method of sealing a raw edge
of asbestos, take appropriate steps to seal the raw edges as approved by
the Contracting Officer.
][3.2.6
Encapsulation Procedures
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NOTE: Choose "Removal Procedures" or "Encapsulation
Procedures" as appropriate for the project.
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3.2.6.1
Preparation of Test Patches
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NOTE: Prior to preparing plans and specifications
for an encapsulation project, the designer will have
to ascertain that encapsulation is feasible at all.
The foremost design criteria is the soundness of the
existing asbestos containing matrix, i.e. the bond
of the matrix to the substrate and the shear
strength of the matrix itself. The designer should
test the existing matrix in accordance with the ASTM
E 1494, using the Field Testing Provisions for the
Adhesion Test.
**************************************************************************
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NOTE: Exercise discretion on the number and
location of Contractor applied test patches.
However, a minimum of three test patches should
always be specified. Test locations, in areas of
the matrix, that have a different appearance or
raise doubts about their homogeneity. Specify
number of test patches in first bracket and location
in second bracket. Also show location on drawings.
**************************************************************************
Install [three] [_____] test patches of encapsulant in [_____], as
indicated. Use airless spray at the lowest pressure and as recommended by
the encapsulant manufacturer. Follow exactly the manufacturer's
instructions for thinning recommendations, application procedures and
rates. Curing time shall be not less than five days or that recommended by
the manufacturer, whichever is more. A test patch shall be 0.8 square meter
9 square feet in size.
3.2.6.2
Field Testing
Field test the encapsulation test patches in accordance with ASTM E 1494,
paragraph "Required Field Test," in the presence of the Contracting Officer.
Keep a written record of the testing procedures and test results. Upon
successful testing of the encapsulant, submit a signed statement to the
Contracting Officer certifying that the encapsulant is suitable for
installation on the particular asbestos containing material.
3.2.6.3
Large-Scale Application
Apply encapsulant using the same equipment and procedures as employed for
the test patches. Keep the encapsulant material stirred to prevent
settling. Keep a clean work area. Change pre-filters in the ventilation
SECTION 13281N
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