Work out machine guard distance instantly with clear inputs, formula shown and shareable results.
Safety distances for reaching through a regular opening depend on which part of the limb can pass. Slots up to 4 mm exclude even a fingertip, 8 mm admits a finger to the first knuckle needing 20 mm clearance, and above 20 mm the whole arm can reach so 850 mm is required. Reaching over a guard is treated separately and depends on guard height.
Reach through
Safety distance rises in steps with opening size: 2 mm at 4 mm opening, 20 mm at 8 mm, 120 mm at 20 mm, 850 mm above 30 mm
Reach over
A 1400 mm guard needs about 900 mm horizontal distance; 1800 mm needs only 100 mm
Preliminary estimate only. Guarding must be designed to the applicable safety of machinery standards by a competent person using the full distance tables.
Safety distance rises in steps with opening size: 2 mm at 4 mm opening, 20 mm at 8 mm, 120 mm at 20 mm, 850 mm above 30 mm. Safety distances for reaching through a regular opening depend on which part of the limb can pass.
Because the limb that fits changes discontinuously. Going from an 8 mm slot to a 12 mm one lets the whole finger through, and the required distance jumps from 20 mm to 100 mm.
This calculator takes 3 inputs: Opening size in the guard, Guard height, Hazard height above the floor. The pre-filled defaults are a realistic worked example — replace them with your own site or project figures.