EN ISO 13857 defines the safety distances that stop people reaching hazard zones over, under, around or through guard openings with their upper or lower limbs.
The 2019 edition tabulates safe distances by opening size, for people aged 14 and over; openings above 120 mm fall outside the tables and need the full clause 4.2.2 treatment. Knox Thomas has a free online calculator built on Table 4 of the standard.


