Updated: Mar 29
It is not only the intensity of the sound that you should be worried about, the length of the time you hear a loud sound is equally dangerous.
Noise is measured using the decibel (dB) scale, which reflects the sensitivity of human ears to different levels and frequencies of sound.
Here are some examples:
0dB: the quietest sound a healthy human ear can hear
40dB: a quiet library
60dB: an ordinary spoken conversation
85dB: a food blender
88dB: heavy traffic
91dB: a pneumatic drill
97dB: an industrial fire alarm
100dB: a nightclub
110dB: a live gig or concert
130dB: an aeroplane taking off 100m away.
140dB is the level at which noise causes pain for most people, although some people may find lower levels painful too.
Dangerous decibel levels
Hearing sound or music below 70dB for a long time is reasonably safe. 85dB is the threshold level at which your hearing can become damaged over time. If you work in a noisy environment and the sound levels reach 80dB, your employer should assess the risk to your hearing and give you information about this.
How long you’re exposed to noise matters
The safe exposure time for 85dB is up to eight hours a day. Remember that you’re exposed to lots of different sounds that are 85dB or over throughout the day, and this exposure time adds up. As sound intensity doubles with every increase of 3dB, the safe exposure time halves. So, for example, the safe exposure time for 88dB is four hours.
You’re at risk of hearing damage after just 15 minutes when you’re in an average nightclub, which plays music at 100dB if you don’t use earplugs to protect your ears. For sounds of 110–120dB, even a very short exposure time can cause hearing damage.
An easy way to tell if noise is too loud
It can be hard to tell how loud sounds are, but if you can’t talk to someone who’s about 2m (6ft) away without shouting because of background noise, it’s likely that noise levels are dangerously high. There are decibel reader apps that are available to download onto your smartphone or tablet, but these should only be used as a guide and aren’t designed for professional use. I use Decibel X to measure the sound/noise level around me if I sense that it is dangerously high. It can be downloaded free of charge from Apple Store.
You may be exposed to noise that’s dangerously loud if you go to music events, listen to music through headphones, shoot for sport, ride a motorbike or use power tools. If you find you can’t hear properly or have ringing in your ears (tinnitus) for a few hours afterwards, it’s a sign you’ve been exposed to noise that’s loud enough to damage your ears and you may have developed a slight and permanent hearing loss. If you keep exposing yourself to loud noise, this damage will become more noticeable and permanent over time. If in doubt I would suggest doing an online hearing test right away.
If noise is so loud that it hurts your ears, you should immediately leave the venue or stop the activity that’s causing the noise – and use hearing protection in future.
Remember, the louder the noise is and the longer you are exposed to it, the higher the risk to your hearing. You can protect your hearing by lowering the volume of music (see how you can set up your iPhone to limit its intensity to safe levels), reducing the time you’re exposed to loud noise, and using earplugs or ear defenders in noisy environments.