Materials specially designed for use as absorbers of electromagnetic waves, or intrinsically conductive polymers, as follows: (a) Intrinsically conductive polymeric materials with a ‘bulk electrical conductivity’ exceeding 10 000 S/m (Siemens per metre) or a ‘sheet (surface) resistivity’ of less than 100 ohms/square, based on any of the following polymers: 1. Polyaniline; 2. Polypyrrole; 3. Polythiophene; 4. Poly phenylene-vinylene; or 5. Poly thienylene-vinylene. Technical note : ‘Bulk electrical conductivity’ and ‘sheet (surface) resistivity’ should be determined using ASTM D-257 or national equivalents.