IEC 62304 and the safety classes¶

IEC 62304 is the medical-device software lifecycle standard. It classifies software into safety classes A, B, and C by the severity of the harm that a failure can cause.

Class C is the highest class, where death or serious injury is possible. Class A is the lowest class, where no injury or damage to health is possible.

The three safety classes¶

Class	Severity	Possible consequence	Example
C	Highest	Death or serious injury possible	Infusion-pump dosing, radiation-therapy control
B	Moderate	Non-serious injury possible	Diagnostic imaging, patient-monitor alarm logic
A	Lowest	No injury or damage to health	Administrative software, data logging

What adacovex checks at each class¶

adacovex evaluates the same four criteria as for DO-178C. Only the class name and the minimum proof bar change.

Requirement traceability and orphan tags¶

Class	Requirement
A to C	Every HLR is traced by a `-- HLR-XXXX` tag, and every tag maps to a defined HLR

Passing tests¶

Class	Requirement
A to C	100% tests passing

Minimum SPARK level¶

Class	Minimum SPARK level
C	Gold
B	Silver
A	Bronze

Mapping to the shared rigour tier¶

The safety classes map onto the shared rigour tier that DO-178C uses. One assessment therefore satisfies both standards at once.

Class	Shared tier	DO-178C equivalent
C	A	DAL-A
B	B	DAL-B
A	C	DAL-C

Assessing at a safety class¶

Select a class with --class, or select the shared tier with --dal:

adacovex --target=. --class=A
adacovex --target=. --class=C
adacovex --target=. --standard=iec62304 --dal=C
adacovex --target=. --standard=all

The report prints the class name in place of the DAL name:

Target level: Class A
Status: Achieved
HLR traced:  24 /  24
Orphan tags: No
Tests passing: Yes
Min SPARK level met: Yes