Understanding noise and echos in classrooms
Understanding noise and echos in classrooms
To help you work out what level the sound in your classroom is likely to be (and whether you need to do anything about it or not), it’s good to have a basic understanding on how sound is measured. When we measure noise levels with a sound meter, we measure how intense the noise is in decibel units – or decibels.
Check Out Some Acoustic Solutions Now!
How do Decibels work?
The human ear is a brilliantly designed hearing device. Its includes a very clever mechanism that reduces the sensitivity as the sound level increases and it also handle a huge range – from a very quiet whisper from the kid sitting beside it, and at the same time it can hear a sports car 2 blocks away from the classroom screaming at 8000 rpm!
The noise level chart (or decibel level chart) below shows the effects of sound at different dB levels in the classroom, and show the effect of sounds and noises at different decibel levels.
Decibels are tricky, because they’re on a logarithmic scale. This means that the quietest audible sound (total silence) is 0 dB. A sound 10 times more powerful than 0 dB is 10 dB. A sound 100 times more powerful than near total silence is 20 dB. A sound that is 1,000 times more powerful than near total silence is 30 dB, 40 dB and so on.
This chart shows basic classroom noises and their decibel rating:
How Many Decibels Is Safe in a classroom?
Now we know how Decibels work, how many decibels is safe in a classroom? In the past, generally speaking sounds of less than 75 decibels have been considered safe even over extended periods of time. However recent research is indicating that repeated exposure to sounds above 60 decibels is too loud and can cause hearing loss, which means that the acceptable noise level for humans is at or below 60 dB. Even though noises around 60 dB are at safe decibel levels for humans, it’s important that you are not exposed for extended periods.
