Andy,
The point I am trying to make is that the difference between band 5 and band 6 according to the Job Evaluation Handbook is that you need "a distinct addition of knowledge to what was acquired during basic training and required for professional practice".
I understand this to mean that a technician working on electro-medical equipment will be on band 5 but a technician working on electro-medical equipment and who has additional knowledge to be able to also service anaesthetic machines will be on band 6.
This is my understanding of the situation and is also the informatomation given to me by my union.
The important statement is 'additional knowledge'.