Derwent Classification System: Instrumentation, Measuring and Testing

Includes electrical aspects of medical equipment, photographic and printing apparatus

S01 Electrical Instruments (G01R, G12B) Measuring magnetic and electrical variables. Instrument panels, housings, indicating elements, screening, suspensions, damping. Cooling arrangements.
S02 Engineering Instrumentation (G01B-H, L, M, P) Measuring dimensions, weight, flow rate, mechanical vibrations, force, acceleration, etc. Recording equipment. General testing methods.
S03 Scientific Instrumentation (G01J, K, N, T-W) Photometry, calorimetry. Thermometers. Meteorology, geophysics, measurement of nuclear or X-radiation. Investigating chemical or physical properties.
S04 Clocks and Timers (G04B-G) Electronic and mechanical clocks and watches. Time switches. Time-interval measuring.
S05 Electrical Medical Equipment (A61, A61N) Electrotherapy. Electrosurgical apparatus. Blood cell counters. Electrical diagnostic apparatus. Tomography. Veterinary apparatus.
S06 Electrophotography and Photography (G03, G03G) Cameras, film projectors and processing (electrical aspects only). Electrography, xerography. Rotary press printers (electrical aspects only).