These specifications and methods of testing apply to cellular-rubber products known as sponge rubbers and expanded rubbers, but do not apply to latex foam rubbers. The base material used in their manufacture may be natural rubber, synthetic rubber, or rubberlike materials, alone or in combination. Ebonite cellular rubbers are not included.
Extruded or molded shapes or sizes too small for cutting standard test specimens are difficult to classify or test by these methods and will usually require special testing procedures.
In cases of conflict between the provisions of this general specification and those of a detailed specification, the latter shall take precedence. References to these methods for testing cellular-rubber products should specifically state the particular test or tests desired.