References
- International Electrotechnical Commission . 1985 . IEC Standard, Publication 804 Geneva
- Acoustical Society of America . 1983 . American National Standard ANSI S1.4 New York
- Acoustical Society of America . 1978 . American National Standard ANSI S1.25 New York
- Air Sampling Instruments for Evaluation of Atmospheric Contaminants, 6th. ed. American Conference of Governmental Industrial Hygienists . Cincinnati : ACGIH .
- American Industrial Hygiene Association . 1985 . Manual of Recommended Practice for Portable Direct-Reading Carbon Monoxide Indicators , Akron : AIHA .
- Occupational Safety and Health Administration . 1980 . Industrial Hygiene Field Operations Manual , R-20 – R-25 . U.S. Department of Labor .