Safety of machinery. Positioning of safeguards with respect to the approach speeds of parts of the human body
 
If you design or manufacture machinery, you’ll already know how important safety is for your business.

Part of designing safe machines is knowing how fast they need to respond. For example, how far away from a spinning blade does an electro-sensitive shut off mechanism need to engage?

Recently revised, BS EN ISO 13855 is an International Standard which establishes the positioning of safeguards with respect to the approach speeds of parts of the human body.

It specifies parameters based on values for approach speeds of parts of the human body and provides a methodology to determine the minimum distances to a hazard zone from the detection zone or from actuating devices of safeguards.

The values for approach speeds (walking speed and upper limb movement) in BS EN ISO 13855 are time tested and proven in practical experience.

BS EN ISO 13855 gives guidance for typical approaches. Other types of approach, for example running, jumping or falling, are not considered in BS EN ISO 13855.

Safeguards considered in BS EN ISO 13855 include:

a) electro-sensitive protective equipment [see IEC 61496 (all parts)], including:

Light curtains and light grids (AOPDs)
Laser scanners (AOPDDRs) and two-dimensional vision systems

b) pressure-sensitive protective equipment (see ISO 13856-1, ISO 13856-2 and ISO 13856-3), especially pressure-sensitive mats

c) two-hand control devices

d) Interlocking guards without guard locking.

BS EN ISO 13855 specifies minimum distances from the detection zone, plane, line, point or interlocking guard access point to the hazard zone for hazards caused by the machine (e.g. crushing, shearing, drawing-in). Protection against the risks from hazards arising from the ejection of solid or fluid materials, emissions, radiation and electricity are not covered by this International Standard.

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