Material information

The following are the most common symbols that may be used on the individual Recognitions to represent the generic material type. The generic material symbols are based upon the terminology developed in the International Organization for Standardization publications covering "plastics-symbols" (ISO 1043) and "rubbers and lattices" (ISO 1629).

Foamed materials

Materials which have been foamed with the introduction of a chemical blowing agent or inert gas may have significantly different properties than the non-foamed or solid material form. Therefore, ratings that are established for solid (non-foamed) material do not automatically apply to the foamed version of that same material.

Investigation of materials used for structural parts in room air conditioners

Where the retention of physical properties for a material have been investigated for structural parts in specific applications, such as room air conditioners, they are so noted in the individual Recognitions and meet a minimum level beyond which consideration depends on the actual design and use of the part.

Materials for use in special environments

Investigation of materials for specific end-use product applications -- where requirements exist for the retention of properties after exposure to certain critical operating and/or environmental conditions -- may be indicated in the individual Recognitions.

Composite materials

These materials consist of a sandwich-type construction of a metal and a plastic and have been tested for flammability only to determine compliance with UL 94. They may also contain an adhesive which serves to bond the individual components into a composite structure.