[SystemSafety] Operational logging for medical devices

[Olwen Morgan]

Aircraft have flight recorders and I've worked on software a neonatal 
ventilator that had operational logging. One thing that bothered me is 
that the rest of the engineers in the company often said of the logging 
that it was not safety-critical and therefore didn't need to be 
developed as strictly as the bits that controlled the air flow to the 
patient.

With modern solid-state storage devices, it is straightforward to write 
an operational log to non-volatile storage but AFAI can see (possibly 
wrongly, please correct me if so) the medical device regulators seem to 
look at it only in cases where it is deemed essential. Given that the 
marginal cost of adding such logging is quite low, I'm inclined to think 
that there should be a general presumption that logging is required 
unless it is proven not to be needed.

Any views?

Olwen