okay 
Yes in certain circumstances, BUT:
- software safety class (in IEC62304:2006) shall be based on the severity of the risk assuming 1oo% probability regardless any artificially created "rational",
- the initial (before mitigation) software safety class can be reduced ONLY if a severity component of the residual risk was reduced,
- the severity of the residual risk can be considered as reduced ONLY if the mitigation (risk control measure if you like) was based on safe design, any other way (protective measure and labeling) only reduce the probability component of the residual risk.
Yes, if the above principles are the case, than yes, you can reduce the software system classification according to IEC62304:2006.
I hope it is common sense, for all software codes or software modules you shall follow the overal software system classification (IEC62304:2006), not the specific module de-compositional classification.
br,
Sz.
62304 explicitly allows you to have Class A (~1) software in is Class 3 device
- software safety class (in IEC62304:2006) shall be based on the severity of the risk assuming 1oo% probability regardless any artificially created "rational",
- the initial (before mitigation) software safety class can be reduced ONLY if a severity component of the residual risk was reduced,
- the severity of the residual risk can be considered as reduced ONLY if the mitigation (risk control measure if you like) was based on safe design, any other way (protective measure and labeling) only reduce the probability component of the residual risk.
Yes, if the above principles are the case, than yes, you can reduce the software system classification according to IEC62304:2006.
Because Class A code requires much, much less process
br,
Sz.