The HSE have issued Diving Information Notice No.10 that amongst other issues gives guidance on the filling of diving cylinders. The guidance includes:-
1. Filling to be completed by COMPETENT persons (competent means having approriate Knowledge , Skills and Training).
2. Operator should wear eye and hearing protection.
3. Restraining lines to be attached to charging whips.
This is interesting advice which no doubt should appear in risk assessments but I have not yet seen these measures in use at cylinder filling stations. The advice does not cover people other than the operator but it does flag up the safety benefit of having filling stations that separate customers from the location in which the filling is conducted.