Remove interior piping to ensure complete coverage of floor and underside
of pipe supports. [Do not coat aluminum floating pan.]
3.9
SURFACE PREPARATION
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NOTE: When editing this specification for
maintenance coating work for which SSPC SP 12 Water
Cleaning or Jetting surface preparation is to be
allowed, include note for the contractor to use
potable water, monitor the quality of the water, and
adjust water quality to assure appropriate surface
preparation and final surface requirements. There
are many problems that might arise from both
dissolved and suspended material. A common
occurrence is water with high-chlorides, even in
potable water, which may leave unacceptable
contamination on cleaned surfaces, and may not be
suitable for water jetting.
**************************************************************************
3.9.1
Abrasive Blasting Equipment
Use abrasive blasting equipment of conventional air, force-feed, or
pressure type. Maintain a minimum pressure of 650 kPa 95 psig at nozzle.
Confirm that air supply for abrasive blasting is free of oil and moisture
when tested in accordance with ASTM D 4285. Test air quality at each
startup, but in no case less often than every five operating hours.
3.9.2
Surface Standard
Inspect surfaces to be coated, and select plate with similar properties and
surface characteristics for use as a surface standard. Blast clean one or
more 300 mm 1 foot square steel panels as specified in Article entitled
"Surface Preparation." Record blast nozzle type and size, air pressure at
nozzle and compressor, distance of nozzle from panel, and angle of blast to
establish procedures for blast cleaning. Measure surface profile in
accordance with ASTM D 4417. When the surface standard complies with all
specified requirements, seal with a clearcoat protectant. Use the surface
standard for comparison to abrasive blasted surfaces throughout the course
of work.
3.9.3
Pre-Preparation Testing for Surface Contamination
Perform testing, abrasive blasting, and testing in the prescribed order.
3.9.3.1
Pre-Preparation Testing for Oil and Grease Contamination
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NOTE: When specifying maintenance painting, use a
water based pH neutral degreaser to avoid damaging
existing coating.
**************************************************************************
Inspect all surfaces for oil and/or grease contamination using two or more
of the following inspection techniques: 1) Visual inspection, 2) WATER
BREAK TEST, 3) BLACK LIGHT TEST, and 4) CLOTH RUB TEST. Reject oil and/or
grease contaminated surfaces, clean [using a water based pH neutral
degreaser ]in accordance with SSPC SP 1, and recheck for contamination
SECTION 09970
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