The Simpson Model 897 is a combination dosimeter and Class S2A sound level meter. It is a portable, easy-to-operate, accurate digital sound measurement instrument designed to meet the requirements of OSHA and international noise exposure regulations. The 897 has a built-in data logger with a 31 hour storage capability. There are two standard output formats available with the data logger, a Centronics compatible parallel printer and an RS-232C serial printer or computer. The 897 also meets the requirements for the American National Standard Institute (ANSI) Specification S1.4-1983 and IEC651 for class S2A sound level meters and American National Standard Institute (ANSI) Specification S1.25-1978 for Personal Noise Dosimeters. Measuring continuous, intermittent and impulsive noise in the standard range from 80 dBA to 130 dBA, the 897 also offers a 50 to 100 dB range where lower sound level analysis is desired. When used as a personal noise dosimeter, the 897 may be worn in a shirt pocket or on a belt. The microphone is provided with a clip which can be attached to the operator’s shirt close to the ear. When used as a sound level meter, the Instrument is hand-held. A front end attachment, properly contoured to avoid interference with incoming sound waves, holds the microphone. The advanced microcomputer, large digital display and special electret-condenser microphone offers easy operation and readability, and excellent performance and reliability.