Question

what is the criteria for a guard having to be used on a machine? select the best option. guards on machines are unnecesary only if you feel like a guard is needed only if your employer decides a guard is necessary if operation exposes you to injury

Explanation:

Machine guards are safety devices. Their purpose is to protect operators from hazards like moving parts, flying debris, etc. If a machine's operation can cause injury (e.g., has moving blades, pinch points), a guard is required. The first option is wrong as guards are necessary in many cases. The second option (personal feeling) is too subjective. The third option (employer's decision alone) ignores safety regulations. The fourth option aligns with safety principles - when there's an injury - exposure risk, a guard is needed.

Answer:

If operation exposes you to injury