ISO 13857 — safety distance calculator

Pick an opening shape and size and the calculator returns the minimum safety distance to the hazard zone per ISO 13857:2019, Table 4. Or enter the available distance and see the largest permitted opening.

s_r e hazard
Opening shape
Opening size e (mm)
sᵣ ≥ mm

Part of body Opening e Slot Square Round
Fingertip e ≤ 4 2 2 2
4 < e ≤ 6 10 5 5
Finger up to knuckle joint 6 < e ≤ 8 20 15 5
8 < e ≤ 10 80 25 20
10 < e ≤ 12 100 80 80
12 < e ≤ 20 120 120 120
Hand 20 < e ≤ 30 850a 120 120
Arm up to junction with shoulder 30 < e ≤ 40 850 200 120
40 < e ≤ 120 850 850 850

Source: ISO 13857:2019, Table 4. Values in mm. Guidance only. Always verify against the current standard for your specific application. Openings larger than 120 mm are not covered by this table.