Hazard Analysis and Risk Assessment

Also known as: HARA

Hazard Analysis and Risk Assessment (HARA) is the systematic method defined in ISO 26262 for identifying hazards in automotive electrical and electronic systems and assigning each hazard an Automotive Safety Integrity Level (ASIL) based on Severity, Exposure, and Controllability.

Last updated: April 2026

Key Facts

Full name: Hazard Analysis and Risk Assessment
Common acronym: HARA
Standard reference: ISO 26262 Part 3
Primary use: ASIL determination in automotive functional safety
Sectors: Automotive (passenger cars, trucks, motorcycles since 2018 revision)
Inputs: Item definition, operational scenarios, hazard catalogue
Outputs: List of hazards with ASIL ratings, safety goals
ASIL classes: A, B, C, D, plus QM (quality management, no FS required)
Risk parameters: Severity (S0 to S3), Exposure (E0 to E4), Controllability (C0 to C3)
Typical course length: 1 to 2 days (HARA workshop), or covered within a 3 to 5 day ISO 26262 course
Common audience: Automotive FS engineers, system architects, safety managers

What is HARA?

HARA is conducted at the start of an automotive functional safety project, after the item definition. The team identifies hazards by considering operational scenarios for the item — for example, an electronic stability control system on a wet road at highway speed. Each hazard is rated for Severity (potential harm to occupants and other road users), Exposure (how often the scenario occurs), and Controllability (how easily a driver or other system could mitigate the hazard). The combination of S, E, and C maps to an ASIL value from QM up to ASIL D. Each ASIL-rated hazard generates a safety goal, which then drives the technical safety requirements through the rest of the development.

How HARA Outputs Drive ASIL

The S/E/C combination feeds an ASIL determination table in ISO 26262 Part 3. Higher Severity, Exposure, and Controllability ratings produce higher ASIL classifications. ASIL D is the highest level and is reserved for hazards with the most severe consequences, frequent exposure, and limited driver controllability. ASIL QM means the hazard does not require functional safety treatment beyond standard quality management.

How HARA Relates to Other Hazard Analysis Methods

HARA is specific to ISO 26262. The aerospace equivalent is Functional Hazard Assessment under SAE ARP4761. The process industry uses HAZOP and LOPA for the same purpose. The machinery sector uses risk graphs from ISO 12100 and ISO 13849. The methods differ but share the same underlying logic: identify the hazard, characterise the risk, allocate a level of integrity to the safety function that controls it.

How Automotive Training Providers Deliver HARA Training

HARA is rarely delivered as a standalone course. Most automotive FS providers cover HARA inside a broader 3 to 5 day ISO 26262 course or as a dedicated 1 to 2 day workshop within a multi-week ISO 26262 certification programme. Practical exercises are essential — most providers use a real or representative item example and walk delegates through the full HARA workflow with worked S/E/C ratings. An LMS supporting HARA training needs cohort scheduling tied to certification cycles, secure case study delivery (HARA examples often involve confidential OEM scenarios), facilitation tools for instructor-led S/E/C exercises, and verifiable certificates aligned to recognised schemes such as TUV.

Common Questions

Is HARA only for ISO 26262?

The acronym HARA is most commonly associated with ISO 26262. Similar methods exist under different names in other sectors: Functional Hazard Assessment in aerospace, HAZOP and LOPA in process, risk graphs in machinery.

Who attends a HARA workshop?

Functional safety engineers, system engineers, vehicle engineers familiar with the operational scenarios, and ideally a project safety manager. Cross-functional input is critical for accurate Exposure and Controllability ratings.

How does HARA output drive ASIL allocation?

Each hazard's combination of S, E, and C maps directly to an ASIL using the determination table in ISO 26262 Part 3. The resulting ASIL drives the rigour required throughout development.

Can HARA be reused across vehicle programmes?

Partially. The hazard catalogue and S/E/C reasoning may transfer between similar items, but each new item definition or operational scenario change requires a fresh HARA review. ISO 26262 explicitly requires reassessment when the item or scenarios change.

Train Your Delegates with Blend-ed

HARA training providers need an LMS built for ISO 26262 certification cycles, confidential case study delivery, and the cross-functional exercises this method demands. Blend-ed runs cohort-based scheduling, secure case study delivery, identity verification at exam, verifiable certificates, and audit-ready records.

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