Standardisation seems to work quite well in aircraft, anaesthetics and nuclear power stations - ever thought why? I'm afraid the De-facto standard in safety critical systems is not necessarily the best for everyone but operators will tend to use what works well and is safe and can at least be trained to recognise standard alarms, even if they don't "like" using them.

A lot of research has gone into each of these areas and a lot of changes have been made, for the better, based on the human factors requirements in high-workload, safety-critical, situations such as this. I'm afraid the legislation and standards are with us Geoff, despite not being perfect, but they're much better than nothing as a guideline to manufacturers of medical devices.