1. para 5.6.1. A precision sound level meter;B.S. 4197,1967
2. para. 6d. Sound level meters (industrial grade);B.S. 3489,1962
3. Comm. electrotech. int. 123. Recommendations for sound level meters.
4. para. 6d. Sound level meters for the measurement of noise emitted by motor vehicles;B.S. 3539,1962
5. para. 3. Method for the measurement of noise emitted by motor vehicles;B.S. 3425,1966