The cover size needed for each test is 800 ± 10 mm
x 650 ± 10 mm. The long dimension shall be cut parallel to
the selvage. The cover may be constructed from smaller pieces of material
provided that the resulting seams are not located within 100 mm of
the area likely to be affected by the test.
The cover shall have triangular cut-outs 325 mm from one end
on both sides. The cutouts shall be so positioned that when assembled
on the test rig the lie of any pile is down the back assembly and
from the hinge to the front of the base frame. The size of these cutouts
shall be approximately 50 mm base and 110 mm high.
Where
a fabric interliner is used, it shall be cut to the same dimensions
and in the same orientation as the cover for fitting to the test rig
under the cover.