1. for the entertainment industry
Rigging, work at height
and rescue training
for the entertainment industry
PowerPoint presentation for delegates attending the FST CPTS forum at the Beacon Arts Centre
Please do not distribute electronically.
Use this presentation only yourself for reference or to deliver ‘live’ to colleagues.
Thank you.
© Total Solutions Group 2015.
a brand within the

2. NRAG defines rigging as: The installation, removal, or other activity
using lifting equipment or accessories,
used in tension, for lifting or supporting
technical requirements for
displays
productions
performances
events
National Rigging Advisory Group
Originally to mandate PLASA to develop the National Rigging Certificate.
Now an advisory group to the UK entertainment industry. All sectors represented from theatre to film and TV, indoor and outdoor events and live music.

3. Secondary suspensions
(‘Safeties’)
A topic of many crew room and tour bus discussions….
Many venues insist on them but it’s not a legal requirement, though it might be a licensing condition
However, the quality of them is sometimes less than ideal, so what’s the point?
Why do we need them – or think we do?

4. So what might fail? Supporting structure Suspension - motor
Rigging (slings etc)
Load integrity
So what might fail?
All of these are possible, but very unlikely under normal circumstances

5. Why would a suspension fail? Supporting structure too weak
Brake slips, hook/chain breaks
Hook or connector releases load
Damaged by fire or heat
Why would a suspension fail anyway?
Here are a few reasons
Supporting structure isn’t up to the job – so check first
Poor maintenance (standards are usually good these days).
Hook or connector releases load– really?
So rig it correctly using appropriate gear.
Damaged by fire or heat – risk assessment. Position stuff so it isn’t affected.
Use fire resistant materials – chain slings.

6. Source: Rigging Conference 2011 – Ron Bonner
Data from Ron Bonner’s excellent hoist failure survey presented at the 2011 PLASA Rigging Conference
Not a scientific survey, just an informal information gathering exercise which to my knowledge had never been done before.
Modern hoists - high quality machines, meeting international standards.
Not a very high risk in relation to the rest of the rigging operation.

7. operating temperature Polyester roundslings 85 0 C
Material
Maximum advised
operating temperature
Polyester roundslings
85 0 C
Steel core wire ropes
100 0 C *
Aluminium loses 15% strength
100 0 C
Aluminium loses 45% strength
200 0 C **
Not a scientific study!
* Building fires can reach about C
** Steel wire rope slings usually use aluminium ferrules
*** Trusses are made from aluminium

8. 250 kgs at 250 degrees C

9. Alloy has become plastic and released its grip at relatively low temperature.

10. Installing safeties is often cosmetic False sense of security
Masks less obvious issues
Creates new risks
Venue often not competent
‘Safeties’ are supposed to stop a load falling.
Safeties are frequenbtly cosmetic which can not unreasonably instil a false sense of security.
If ‘the safeties are on’ it can make people think the situation is ‘safe’ and they switch off.
Masks more important but less obvious issues
like the integrity of the supporting structure or load.
Putting safeties on or taking them off, especially if in a hurry, creates probably higher risks than the ones you’re trying to reduce.
Lastly, venue staff/enforcement officers will often not have the confidence or competence to check the installation.

11. Safeties not needed with double braked hoists – wrong.
Category B hoists (D8 in Germany) are industrial hoists
Can be used for suspension of loads but not over people without secondary measures (secondaries etc)
Yellow Book and CWA both state that standard hoists (Category B or D8, D8+) can be used to suspend loads overhead (not move loads overhead) but only at 50% of rated capacity.
Some hoist myths explained -
C1 systems are a legal requirement in Germany
(BGV Regulations) when moving loads overhead.
Double brakes and enhanced factors of safety are only part of the C1 specification. The control system, user training and maintenance programmes are also specified to achieve C1.
Category A hoists (BS7905 and BS7906) are intended by the manufacturer to move or lift loads over people.
Using C1 or Category A hoists does not make other precautions unnecessary.
Risk assessment is the key.
It doesn’t matter how many brakes you have if the chain breaks.

12. (Source: The ‘Yellow Book’)
Yellow Book has been edited to reflect this more up to date thinking and risk management approach.
Previously it made very general requirements that didn’t really match today’s methodology with regard to rigging with trusses and chain hoists.
(Source: The ‘Yellow Book’)

13. OK, so back in the civic hall or arena
How many suspensions do we need?

16. We could just beef up the roof, suspensions and truss
But if you can’t then adding suspensions seems the obvious way forward.

17. What would happen if one support failed? Are we worried it will?
Over engineering

18. 500 kgs can quickly become 5000 kgs unless safety is taut

19. Taut If ‘safeties’ are relied upon they should be:
Rigged as if they were primaries
Made to an independent structure
Of at least equal strength as primaries
Taut
In summary - IF you decide to use ‘safeties’

20. Quantity of suspensions is as important as strength.
Use ‘redundancy’ in the quantity of suspensions
Load, lifting equipment and the supporting structure are as important as hoists and their chain bags
Quantity of suspensions is as important as their strength.
Properly installed secondaries may be appropriate in many circumstances.
Often the most reliable way to is to use ‘redundancy’ in the quantity of suspensions (e.g. four suspensions where two would suffice) instead of fewer lifting machines and secondary measures.

21. So with three suspensions on a truss
what will happen in the event of failure?

22. If the truss or bar is stiff enough not to bend and break

23. If the truss is strong enough to deal with the increased span

24. Or strong enough to deal with the resulting cantilever

25. If you use redundant suspensions (where possible – there may not be enough support points above)
You probably won’t even notice if something fails

26. If you use redundant suspensions (where possible – there may not be enough support points above)
You probably won’t even notice if something fails

27. If you use redundant suspensions (where possible – there may not be enough support points above)
You probably won’t even notice if something fails

28. If you use redundant suspensions (where possible – there may not be enough support points above)
You probably won’t even notice if something fails

29. Riggers’
forum
Riggers’ Forum
18th Jan 2017
SECC
Free to attend.

30. The global event for the rigging community
PowerPoint presentation for delegates attending the FST CPTS forum at the Beacon Arts Centre
Please do not distribute electronically.
Use this presentation only yourself for reference or to deliver ‘live’ to colleagues.
Thank you.
© Total Solutions Group 2015.
The global event for
the rigging community