This decibel (dBA) table compares some common sounds and shows how they rank in potential harm to hearing. In many industries, workers are exposed to dangerous noise levels. This is particularly true in the construction, lumber, mining, steel and textile industries.
140
Shotgun Firing
130
Jet Takeoff (100-200 Ft.)
130
Rock Concert (Varies)
110-140
Threshold of pain
(125 dB) Oxygen Torch
121
Discotheque/Boom Box
120
Threshold of sensation (120 dB)
Thunderclap (Near)
120
Stereo (Over 100 Watts)
110-125
Symphony Orchestra
110
Regular exposure of more than 1 minute risks permanent hearing loss (over 100 dB) Power Saw (Chain Saw)
110
Jackhammer
110
Snowmobile
105
Jet Fly-over (1000 Ft.)
103
Electric Furnace Area
100
No more than 15 minutes of unprotected exposure recommended (90-100 dB)
Garbage Truck/Cement Mixer
100
Farm Tractor
98
Newspaper Press
97
Subway, Motorcycle (25 Ft)
88
Very annoying
Lawnmower, Food Blender
85-90
Level at which hearing damage (8 hrs.) begins (85dB)
Recreational Vehicles, TV
70-90
Diesel Truck (40 Mph, 50 Ft.)
84
Average City Traffic Noise
80
Annoying; interferes with conversation; constant exposure may cause damage
Garbage Disposal
80
Washing Machine
78
Dishwasher
75
Vacuum Cleaner
70
Intrusive; interferes with telephone conversation
Hair Dryer
70
Normal Conversation
50-65
Quiet Office
50-60
Comfortable
(under 60 dB)
Refrigerator Humming
40
Whisper
30
Very quiet
Broadcasting Studio
30
Rustling Leaves
20
Just audible
Normal Breathing
10
Threshold of normal hearing (1000-4000 Hz)
Since the sensitivity of the ear to sound is not the same for all frequencies, weighting or attenuating filters are included in the sound level meter's circuits to simulate the ears' response. A noise level meter gives an instantaneous measurement of the noise present, but cannot measure the duration of the exposure.
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