A bit of mentoring !!! Unfortunately, I have to strongly disagree Geoff, your own generic certificated course via Arborfield (many moons ago) gave you excellent grounding in medical engineering, without which you would not have been allowed anywhere near a military hospital wksp, so why should it be different for anyone else. Once you have achieved a level of approved generic training in medical equipment, then I agree having some old Tom (in your case Sgt Wally-A) undoubtedly helped you enormously. But first and foremost all medical engineering staff ( in my opinion) require approved generic and specific technical training on medical devices, combined with in house support from the more experienced engineers. This is of course in addition to approved academic technical training such as Certificate/HNC)/Diploma/Degree in electronic engineering.
It just so happens, that in January 2015 Avensys will be offering a range of distance learning, online courses for the medical engineering community, from level 3 to Hons degree in medical engineering, electronics, mechanical engineering and mathematics. Accreditation to prior learning and experience is allowed wether your 18 or 65. There can no longer be any excuse stating "such courses are simply not available". They are....soap box/sandbags away for the night.