Covers earth leakage circuit-breakers for use on both direct and alternating current systems at low or medium pressures. An earth leakage circuit-breaker intended for use in a direct current circuit shall be deemed suitable for such use if the earth leakage tripping coil opens the circuit-breaker under the conditions set out in this specification when direct current pressures are applied, and if it otherwise conforms with the requirements of this specification.
Acoustics - Reference zero for the calibration of audiometric equipment, Part 2: Reference equivalent threshold sound pressure levels for pure tones and insert earphones
