The condition of the test specimen can be monitored and
verified by use of special samples for the determination of moisture
content of constituent materials, as appropriate. These samples should
be so constructed as to represent the loss of water vapour from the
specimen by having similar thicknesses and exposed faces. They should
have minimum linear dimensions of 300 mm by 300 mm and a minimum mass
of 100 g. Constant weight should be considered to be reached when
two successive weighing operations, carried out at an interval of
24 h, do not differ by more than 0.3% of the mass of the reference
specimen or 0.3 g, whichever is the greater.
Other reliable methods of verifying that the material has
reached equilibrium moisture content may be used by the testing laboratory.