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Sound Power Testing Techniques for Powered Hand Tools. Brian Kim Edward Zechmann, M.S. Chuck Hayden, M.S., P.E. Dept of Health and Human Services US Public Health Service Centers for Disease Control and Prevention National Institute for Occupational Safety and Health. Overview.
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Sound Power Testing Techniques for Powered Hand Tools Brian Kim Edward Zechmann, M.S. Chuck Hayden, M.S., P.E. Dept of Health and Human Services US Public Health Service Centers for Disease Control and Prevention National Institute for Occupational Safety and Health
Overview • Approx. 70 tools tested since April 2009 • Standards • Facilities and Equipment • Set up at Unloaded and Loaded Condition • Comparisons of Unloaded and Loaded Conditions
Standards • ANSI S12.15-1992 • Tool Testing Standard • Specifies Test Jigs • Loading conditions • ISO 3744:1994(E) • Measurement Standard • 10-Microphone Array • Engineering Grade Standard
Equipment and Facilities • Measure Sound Power • Sound Intensity integrated over measurement surface • Laboratory Environment • Hemi-Anechoic Chamber • Monitoring Equipment • Electrical power, humidity, speed, feed rate, etc.
Hemi-Anechoic Lab Steel Structure 11th Microphone One Microphone of the ten-microphone array Reference Sound Source (RSS)
Loaded Test Jig • Circular saw • Tools held by hand to cut wood • Oak Boards Resiliently Mounted
Continuous Noise in Both Loaded and Unloaded Conditions Idling Full SpeedLower Amplitude97 dBA Cutting Oak BoardsGreater Amplitude109 dBA Circular Saw Milwaukee 6390-20