There are a few things you should know about sound and how its measured.

measuring-soundNoise affects us everyday; at home, at leisure, during sleep, when traveling and at work. Taking an active role in making a room soundproof is not only soothing but could also yield noticeable health benefits. Below are a few things you should know about sound and how its measured.




What is STC?

STC stands for Sound Transmission Class. This is a method of gauging sound transmission loss through a wall. The American Standards and Testing Materials criteria is universally accepted by architects, designers, manufacturers, contractors and distributors of acoustical building products. The original acceptability of STC 34 walls must be reconsidered with the advent of increasing noise pollution.
STC Assessment:

Poor: 30 – 39
Good: 40 – 49
Better: 50 – 59
Excellent: 60 – 69

What are dBs?

While an STC rating is given in terms of points, the data is given in terms of decibels. A decibel, or dB, is a unit measure reflecting “how loud” a sound is. A sound pressure level of 0 dB represents the threshold of hearing in the most sensitive frequency range of a young, healthy ear, while the thresholds of tickling or painful sensations in the ear occur at about 120 to 130 dB.
Noise pollution:
In general, noise pollution refers to any noise irritating to one’s ear which comes from an external source.

Sound Levels and Human Response

Common Sound  Noise Level  Effect
Hearing begins 0 dB 
10 dB  Just Audible 
Broadcasting Studio 20 dB 
Soft whisper  30 dB  Very quiet 
Quiet Office  40 dB 
Light Auto Traffic  50 dB  Quiet 
Speech  60 dB 
Noisy Restaurant  70 dB  Intrusive 
Alarm Clock  80 dB 
City Traffic  90 dB  Annoying 
Garbage Truck  100 dB 
Rock Concert  110 dB  Very Loud 
Jet Taking Off  120 dB 
Thunderclap  130 dB  Extremely Loud 
Air Raid Siren  140 dB 
Rocket Launching  180 dB  Hearing loss 

Now that we understand roughly what sound is and how sound is measured let’s identify the two main noise problems that people are dealing with. Read: Identify Your Noise Problem