Two pieces, one 450 ± 5 mm x 300 ± 5 mm x
75 ± 2 mm thick, and the other 450 ± 5 mm x 150 ±
5 mm x 75 ± 2 mm thick are required for each test.
Some cushioning assemblies may consist of several layers that
may be typically felt, wadding or different foams. In these cases
the test pieces shall reproduce the upper 75 mm of the cushioning
assembly.
Where the filling is less than 75 mm thick,
the test piece shall be built up to the required thickness by adding
to the underside a further layer of the bottom material.