The enquirer was recently told by the company he was working for that it is against health and safety regulations to wear just one personal headphone in the work place.
There are no specific health and safety regulations that ban the use of headphones in the workplace. However, in workplaces where there are risks such as moving vehicles it seems reasonable (and is not uncommon) for the use of personal headphones to be banned on the basis of an assessment of the risk. Good employers should consult with their staff or their representatives over what is reasonable in relation to use of personal headphones and from the information available it is not clear whether this has happened.
Source Article from http://www.hse.gov.uk/myth/myth-busting/2013/case206-headphones-workplace.htm
Case 206 – Wearing personal headphones in the workplace
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