Safety Chains & Safety Bonds - Regulations
There are no "regulations" that specifically cover the secondary safety bonding of luminaires, however what is important is that the bond meets the requirements of the stage and studio luminaire safety standard - European Standard EN 60598-2-17:1989 (British Standard BS 4533:102.17:1990 and international standard IEC 60598-2-17:1984 are identical). This standard should be applied for CE Marking purposes in Europe.
Clause 17.6.6, on secondary suspension, states:
"A secondary suspension shall be provided for the luminaire ... this secondary suspension shall be designed and mounted in such a way that even in the event of failure of the primary suspension, no part of the luminaire can fall.
Compliance shall be checked by the following test:
With the end of the secondary suspension remote from the luminaire securely fixed, the luminaire is allowed to hang freely by means of the secondary suspension alone. The luminaire is raised in its hanging mode a distance of 300mm vertically and allowed to fall freely. This test is made 30 times. The secondary suspension shall not fail and no part of the luminaire shall fall."
Given the 300mm figure in the safety standard, PLASA recommends that safety bonds are fixed so that they do not allow the luminaire to move more than 150mm from its primary position (in the event that a luminaire is lifted 150mm before a fall, the fall would be 300mm).
BS and ISOs have no legal status however, if following an accident or incident, any relevant standards would be used as indicators to best practice, so compliance to them would be seen as meeting relevant conditions to legal provisions, namely the Health and Safety at Work Act or any other regulations (Electricity at work Regulations, Management of Health and Safety at Work Regulations etc.)