General Tools and Instruments DSM8925 - Manual (Page 12)

curve simulates the response of the human
ear, and is therefore the better choice for
measuring the sound level of an environment
for the purpose of regulatory compliance,
workplace design or noise-pollution control.
By comparison, the “C” weighting curve is
flatter, and is therefore better for measuring
the sound level of a piece of machinery. In the
U.S., most OSHA-mandated sound level
measurements are made by instruments set
for slow response and “A” frequency
weighting.
To switch from “A” frequency weighting to
“C” weighting, press the A/C button. The
letter at the right of the display will change
from A to C. To switch back to “A” frequency
weighting, press the A/C button again.
STORING AND RECALLING
MIN AND MAX READINGS
The DSM8925 can also operate in
“Recording” mode, for the purpose of tracking
and displaying minimum and maximum sound
level measurements.
To enter Recording mode, press the REC
button briefly. The text REC will appear at the
upper left of the display.
To display the minimum sound level
measured since entering Recording mode,
press the REC button briefly again. The text
MIN will appear on the top line of the display
and the digital display will indicate the lowest
sound volume measured during this recording
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