Much as I dislike e-training, this may be the ideal situation for TBT level information dissemination.

Set up a contract with one of the on-line companies such as Ihasco, Hays, Safety Media etc etc and allocate them a different subject to cover each month (or more often). Can easily be done working from home and doesn't cost a fortune.

Also provides an audit trail for delivery and completion.

I'm in the same boat. 35 mobile engineers working from Devon across to London and up to Birmingham, and now a client in Telford. Some don't visit the office for months. Company cars go to service at a garage local to them, all jobs issued online via a tablet system.

Online training is the only option available to me that doesn't cost the earth. MD won't have training days or me chasing around the SW conducting TBT. If we have a big job on, like we did last year, we had several AC installers onsite in Newbury for 3-4 months, I'd go and visit them but they'd have TBT from the main contractor so I just sat in, listened and copied the sign off sheet for our records.