Glossary · Risk assessment and risk reduction
Inherently safe design measure
Also known as: inherent safety by design
German: Inhärent sichere Konstruktionsmaßnahme
In machine safety, an inherently safe design measure is a design measure that eliminates a hazard or reduces risk without relying on guards, protective devices or user behavior, for example by changing the design or the operating characteristics of the machine. It is the first step of the three-step method.
- Machine safety
- Risk assessment
In one sentence
Inherently safe design measures remove hazards or lower risk through the machine design itself, and ISO 12100 makes them the first choice in risk reduction.
Example
A conveyor designer limits the gap between belt and frame so fingers cannot be drawn in, and reduces drive force so a trapped hand cannot be crushed.
How it applies
- Machine safety: Typical measures are avoiding sharp edges, keeping minimum distances to prevent crushing, limiting force, speed and energy, choosing safe materials, placing adjustment and maintenance points outside hazard zones and applying ergonomic principles.
- Risk assessment: Consider design measures first for every hazard. Only when they cannot reduce the risk enough should safeguarding follow.
- Technical documentation: Design measures are easy to overlook in documentation because they are invisible to the user. Record them in the risk assessment and the technical file, with the design data that proves them.
- Change control: A later design change can silently undo an inherently safe measure, for example a stronger motor. Link these measures to change impact analysis.
Inherently safe design measure vs. safeguard
A safeguard leaves the hazard in place and keeps people away from it or stops it. An inherently safe design measure removes the hazard or reduces it at the source, so it cannot be bypassed.