LaserLiner MultiTest-Master Manual page 11

Reference values for illuminance in outdoor spaces
Practical example
Sunshine
Overcast
Good street lighting
Full moon
8 Sound pressure level (dB)
This device registers sound in a similar way to the human ear. The
integrated microphone receives the incoming sound waves and
converts them into electrical signals. Human hearing involves speci c
auditory curves. The greater the sound pressure, the louder the
sound is perceived to be. The higher the frequency, the higher the
pitch of the sound is perceived to be. To ensure that measurements
are aurally compensated, this measuring device is tted with lters.
The A-weighting (dB A) replicates the frequency response associated
with human hearing and is used for the majority of industrial noise
and environmental noise measurements. The C-weighting is used in
the case of scienti c measurements, for example.
After switching on the device, press the „dB" button. To switch
between dB (A) and dB (C), press the „Unit" button. Point the
microphone towards the relevant sound source and observe the
relevant distance. By pressing the „Mode" button, you can get the
device to display the highest (MAX), lowest (MIN), average (AVG)
or difference value (DIF) in addition to the current measured value.
As its name suggests, the „HOLD" button enables you to hold the
current measured value.
!
Powerful wind noises (> 10m/s) can affect the measured value. In such cases, you should use the
wind de ector supplied with the product.
Sound source
Auditory threshold
Quiet residential area
Low-level conversation, quiet of ce
Normal conversation
Heavy road traf c
Shouting, screaming
Pneumatic hammer (10 m away)
Start-up of a jet aircraft (100 m away)
Pain threshold
MultiTest-Master
Luminous intensity in lux
50,000 – 100,000
2000 – 10,000
20
0.01 – 0.1
TEMP/%RH
MODE MODE
dB
UNIT HOLD
Sound pressure level in dB (A)
0
30 to 40
40 to 50
50 to 60
70 to 80
80 to 85
90 to 100
120 to 130
140
SET
GB 11