Health and Safety Executive's guide, Noise at work: Advice for employers, says that having a noise problem at work depends on how loud the noise is, and how long people are exposed to it. Both the level and duration of the sound have to be taken into account.
The HSE says there is a noise problem at work if:
Remember the 'two-metre rule' – if it is so noisy that you find it difficult to communicate with a fellow worker who is just two metres away, the noise is loud enough to damage your hearing.
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