ISO 26262 and the ASIL levels¶

ISO 26262 is the automotive functional-safety standard. It applies the same rigour to road-vehicle software, such as braking, steering, and powertrain control. Every item is assessed at one of four Automotive Safety Integrity Levels (ASIL A to ASIL D), or as quality-managed (QM).

The ASIL follows the severity of the hazard. ASIL-D covers an uncontrolled, life-threatening malfunction, and QM covers software with no safety effect.

The ASIL levels¶

ASIL	Severity	Failure condition	Example
D	Catastrophic	Uncontrolled, life-threatening malfunction	Steering or brake-by-wire, airbag deployment
C	Hazardous	Severe injury, survival uncertain	Stability control, adaptive cruise control
B	Major	Non-fatal injury possible	Lane-keeping assist, headlamp control
A	Minor	No injury, limited function loss	Window or sunroof control, seat adjustment
QM	No effect	No safety effect	Infotainment, navigation

What adacovex checks at each level¶

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

Requirement traceability and orphan tags¶

ASIL	Requirement
A to D	Every HLR is traced by a `-- HLR-XXXX` tag, and every tag maps to a defined HLR
QM	Recommended, not enforced

Passing tests¶

ASIL	Requirement
A to D	100% tests passing
QM	No requirement

Minimum SPARK level¶

ASIL	Minimum SPARK level
D	Gold
C	Silver
B	Bronze
A	Stone
QM	None

Mapping to the shared rigour tier¶

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

ASIL	Shared tier	DO-178C equivalent
D	A	DAL-A
C	B	DAL-B
B	C	DAL-C
A	D	DAL-D
QM	E	DAL-E

Assessing at an ASIL¶

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

adacovex --target=. --asil=B
adacovex --target=. --asil=D
adacovex --target=. --standard=iso26262 --dal=C
adacovex --target=. --standard=all

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

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