Anyone any experience of dealing with this situation. We have a mandatory hearing protection policy but noticed a couple of personnel using I PODs (wires from ear phones coming under ear defenders).

Rich, Come across this before, local noise level 100 dB ipod earphones inside earmuffs measured 115-120 dB and the stupid blighter was still wearing them the next day after instructing him to remove them or go deaf. Badger

I would also ban the use of IPods etc in the workplace. To distracting.

Surely nothing like as much as the effect of the pads going over the arm of glasses, and the ear-defender manufacturers reckon that is acceptable (if liquid-filled cushions to the ear defenders, and flattish glasses arms). I'd be surprised if an earphone wire made significant difference - how recently you shaved and the subtleties of bone profile would be as significant, wouldn't they?

Just to approach from another side.... if the job is REALLY boring or repetitive there are solutions that allow radio, or MP3s to be listened too. You can also allow radio comms so you can talk to your staff (broadcasting inspirational messages or something) or even have them in a conference call so they can talk to each other. If you're feeling really plush machines can send messages into this chaos of information asking for attention. All this with active attenuation or front speakers that feed in external noise at a safe level.... This means alarms are heard, the employee gets to chill to Machine Head or equivalent, and safety isn't compromised. Another interesting point is personal radio isn't subject to the same licensing rules so you don't need a license like you do for a 'public' radio system. I learnt all this from peltor (3M) (other companies exist), so if you are feeling kind and have money to burn call them.. if not ban mp3 players.