of sand. Note that the results of this test are
variable and offer poor repeatability. Where
greater than 65 liters of sand abrasion resistance
is specified, coordinate with coating type specified.
**************************************************************************
When subjected to the falling sand test in accordance with ASTM D 968,
Method A, the coating system shall withstand a minimum of [50] [80] [100]
liters of sand before the appearance of the base metal. The term
"appearance of base metal" refers to the metallic coating on steel or the
aluminum base metal.
2.2.1.7
Specular Gloss
**************************************************************************
NOTE: Specify the first bracketed option for most
roof conditions.
For roofs of structures along airfields where glare
would be objectionable and may be an operational
hazard, the specular gloss value should be limited
to 10 or less at an angle of 85 degrees. Limited
paint systems can meet this reflectance value.
Panel embossing also reduces the gloss, or
reflectance value, and may be specified in
combination with the paint system specification to
meet the necessary requirement
**************************************************************************
Finished roof surfaces for shall have a specular gloss value of [30 plus or
minus 5 at an angle of 60 degrees] [10 or less at an angle of 85 degrees]
when measured in accordance with ASTM D 523.
2.2.1.8
Pollution Resistance
Coating shall show no visual effects when covered spot tested in a 10
percent hydrochloric acid solution for 24 hours in accordance with ASTM D
1308.
2.3
ACCESSORIES
Accessories shall be compatible with the metal roof panels. Sheet metal
flashing, trim, metal closure strips, caps, and similar metal accessories
shall be not less than the minimum thicknesses specified for roof panels.
Exposed metal accessories shall be finished to match the panels furnished[,
except as otherwise indicated]. Molded foam rib, ridge and other closure
strips shall be closed-cell or solid-cell synthetic rubber or neoprene
premolded to match configuration of the panels and shall not absorb or
retain water.
2.3.1
Pre-manufactured Accessories
**************************************************************************
NOTE: Include the following general paragraph.
Add subparagraphs for specific accessory materials
requirements as required for the specific project
and components to be installed.
Accessory components might include ridge vents,
SECTION 07412
Page 19
Previous Page
