Hazard

Section 06: System Safety & Functional Safety

Definition

A condition, event, or circumstance that could lead to or contribute to an unplanned or undesired event resulting in harm. In aviation system safety, a hazard is typically a failure condition or combination of failure conditions at the aircraft or system level that, if not mitigated, could result in injury, death, or damage. Hazards are identified through systematic analysis processes such as Functional Hazard Assessment (FHA) and are characterized by their potential severity and likelihood.

Where This Shows Up

Hazard identification is the starting point of the safety assessment process. The FHA systematically identifies failure conditions (hazards) at the aircraft and system level, classifies their severity, and establishes safety objectives. Subsequent analyses (PSSA, SSA) then demonstrate that the design achieves the required level of safety for each identified hazard.

Primary Sources

SAE ARP4761A — Safety Assessment Guidelines

Provides definitions and methodology for hazard identification and assessment.

SAE ARP4754B — Guidelines for Development of Civil Aircraft and Systems

Addresses hazard identification in the context of the aircraft development process.

Related Terms

Need help navigating certification?

Understanding the terminology is the first step. If you need expert guidance on DO-178C, DO-254, ARP4754B, or any aspect of FAA, EASA, or TCCA certification, our team is here to help.