1. BS 3489:1962, Sound level meters (industrial grade); BS 4197:1967, A precision sound level meter, British Standards Institution, London
2. International Electrotechnical Commission, IEC Standard 651, Sound Level Meters, IEC, Geneva (or British Standards Institution. London) (1979)
3. H.M. Government, The Noise at Work Regulations 1989, SI 1989 No. 1790, HMSO, London (1989)
4. Acoustic Noise Measurements;Hassall,1979
5. Control of Pollution Act 1974, part III, HMSO, London (1974)