| ACOUSTICS |
| Artificial ear & audiometric |
| Mechanical coupler - audiometric |
| Microphone systems, free field sensitivity |
| Microphones, free field sensitivity |
| Microphones, pressure sensitivity |
| Pistonphones |
| Reference couplers - audiometric |
| Sound calibrators |
| Sound level meters, free field response |
| CHEMICAL |
| Gases |
| DIMENSIONAL |
| Angle gauges, precision |
| Autocollimator and angle dekkors |
| Cylindrical setting standards |
| Extensometer calibrating rig |
| Gauge blocks (by interferometry) |
| Graticules |
| Indexing tables |
| Laser frequency |
| Laser interferometer systems |
| Length bars |
| Linewidth standards |
| Plain plug gauges, parallel |
| Plain ring gauges, parallel |
| Plain setting rings, parallel |
| Polygons |
| Reference stage graticules |
| Roundness, reference standards |
| Screw thread gauges, API |
| Stage micrometers |
| Thread measuring cylinders |
| ELECTRICAL |
| AC/DC Transfer devices |
| Air lines |
| Antennas |
| Attenuators, rf/microwave |
| Bridges and similar instruments, capacitance |
| Bridges and similar instruments, inductance |
| Capacitance boxes |
| Capacitance meters |
| Capacitors |
| Capacitors, high voltage |
| Current shunts |
| Current transformer test sets |
| Current transformers |
| Dividers, high voltage ac |
| Dividers, high voltage dc |
| Electrical Conductivity Reference Standards |
| Field strength meters |
| Flicker meters |
| Flux integrators |
| Flux meters |
| Flux sources |
| Hall effect meters |
| Helmholtz coils |
| Inductance boxes |
| Inductive voltage dividers |
| Inductors |
| Magnetic measurements |
| Magnetometers, fluxgate |
| Mutual inductors |
| Noise sources, rf/microwave |
| Oscilloscope calibrators |
| Oscilloscopes, deflection coefficients and risetime |
| Power meters, rf/microwave |
| Power reference sources |
| Power sensors |
| Power supply units |
| Pulse generators |
| Reference magnets |
| Resistance boxes |
| Resistance meters |
| Resistors, ac |
| Resistors, dc |
| Search coils |
| Selective error current transformers |
| Selective error voltage transformers |
| Shunts |
| Solenoids |
| Standard cells |
| Terminations and mismatches, rf/microwave |
| Thermistor mounts |
| Voltage measurement standards, ac |
| Voltage standards, ac |
| Voltage standards, dc |
| Voltmeters, ac |
| Voltmeters, dc |
| Voltmeters, rf |
| Voltmeters, vlf ac |
| Wattmeter calibrators |
| Wattmeters, dc |
| Wattmeters, lf |
| Wattmeters, rf |
| FIBRE OPTICS |
| Chromatic dispersion |
| Fibre length |
| Fibre optic attenuators |
| Fibre optic cable |
| Fibre optic power meters |
| Mode field diameter |
| Numerical aperture |
| Optical spectrum analysers |
| Single mode fibre attenuation |
| FORCE |
| Load cells (excluding proving devices) |
| Proving devices and load cells |
| Ratio meters, ac & dc |
| Strain cylinders (foote meters) |
| HUMIDITY |
| Dew point instruments |
| Relative humidity instruments |
| Relative humidity instruments, temperature sensors incorporated |
| MASS |
| Mass |
| OPTICAL |
| Colour temperature |
| Illuminance |
| Laser energy meters |
| Laser power meters |
| Luminous flux |
| Luminous intensity |
| Optical components |
| Optical density standard filters |
| Photometers |
| Reflectance |
| Regular transmission density |
| Spectral response |
| Spectrophotometers |
| Tristimulus values |
| Ultraviolet Response |
| Wavelength standard filters |
| PRESSURE |
| Gas absolute, dead-weight testers, effective area |
| Gas absolute, devices with an electrical output |
| Gas absolute, indicating instruments |
| Gas gauge, dead-weight testers, effective area |
| Hydraulic gauge, dead-weight testers, effective area |
| RADIOLOGICAL |
| Personal dosemeters, neutron |
| Radiation protection instruments, neutron |
| Radiation therapy instruments |
| Radioactive sources, alpha, beta, photons |
| Radioactive sources, neutrons |
| TEMPERATURE |
| Blackbody sources |
| Fixed point cells |
| Radiation pyrometers, optical, disappearing filament |
| Radiation pyrometers, radiation, e.g. pyroelectric |
| Radiometers |
| Resistance thermometers, calibration by comparison |
| Resistance thermometers, fixed point calibrations |
| Standard lamps, gas-filled, blackbody |
| Standard lamps, gas-filled, cylindrical envelope |
| Standard lamps, gas-filled, high stability |
| Standard lamps, vacuum type, blackbody |
| Standard lamps, vacuum type, cylindrical envelope |
| Standard lamps, vacuum type, high stability |
| Temperature indicators and recorders, with temperature sensor(s) |
| Thermal conductivity, calibration |
| Thermocouples, base metal types, e.g. K, N, T |
| Thermocouples, compensating cables |
| Thermocouples, platinum/rhodium types, e.g. S, R |
| ULTRASONICS |
| Hydrophones, reciprocity method |
| Hydrophones/projectors, free field sensitivity |
| Hydrophones/projectors, substitution |
