What types of machine guards are there?
Fixed, interlocked, adjustable and presence-sensing guards, plus two-hand and hold-to-run controls.
Machine guards fall into a few broad families. The goal is the same in every case: keep people out of the danger zone, or stop the hazard before they reach it.
Fixed guards
Permanently attached barriers, removable only with tools. Simple and reliable. Best where access is rarely needed.
Interlocked guards
Movable doors or covers linked to the controls. Opening the guard stops hazardous motion, and the machine won’t restart until it’s closed.
Adjustable and self-adjusting guards
Barriers that adapt to different stock sizes, common on saws and some cutting machines.
Presence-sensing devices
Light curtains, safety mats and laser scanners detect a person entering a zone and stop the machine.
Other safeguards
- Two-hand controls that keep both hands away from the hazard
- Hold-to-run controls for setup
- Distance and awareness barriers
Check them
Guards only work if they are in place and functioning. Test interlocks and sensors regularly, and treat a bypassed guard as a serious defect.
General information, not compliance advice. See machine safety controls.