Standard for safety distances
July 1st 2008 A new standard for safety
distances came into force on 30
April 2008. BS EN ISO 13857:2008
Safety of machinery. Safety
distances to prevent hazard zones
being reached by upper and lower
limbs replaced both BS EN
294:1992 Safety of machinery.
Safety distances to prevent danger
zones being reached by the upper
limbs and BS EN 811:1997 Safety
of machinery. Safety distances to
prevent danger zones being
reached by the lower limbs.
These two standards were
superseded and withdrawn as of
30 April 2008. Note that the new
standard also cancels and replaces
ISO 13852:1996 and ISO
13853:1998, the ISO equivalents to
the old European standards.
In reality it is likely that few
people actively designed
safeguards to comply with the
requirements of EN 811, as
physical guards usually extend
almost to floor level and, in any
case, designers generally assume
that access will be attempted
using the upper limbs. In the new
standard, the material relating to
reach distances for lower limbs is
contained in a single sub-clause
4.3 that states that, in general,
'safety distances should be
determined using Tables 1 to 6 for
the upper limbs.' In situations
where it is not foreseeable that
upper limbs can have access to
the opening, then further data is
provided in Table 7. Annex B gives
safety distances for situations
where Tables 1 to 7 cannot be
used. Something to note is that the
standard's scope covers people of
14 years and older for upper and
lower limbs, and children older
than three years where reaching
through openings, needs to be
addressed.
In addition, the standard
assumes (sub-clause 4.1.1) that a
person does not jump or climb, or
use aids such as chairs, ladders,
tools or rods. When a risk
assessment is being carried out, it
would be prudent to challenge
whether these assumptions are
valid for the anticipated use of the
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