Whether you light theatres, arenas, schools or village halls there is going to come a time where you’re going to need to rig lights to some form of bar or truss. When this day comes it is extremely important to ensure that safety is your number one priority, as the industry in which we work can be very hazardous to both the event crew and the general public. This guide to safe rigging is aimed at those who are perhaps new to rigging or just want to refresh on the basics, for those looking for more advanced rigging training check out: http://www.ukrigging.net/training.php. They offer a number comprehensive rigging courses that are often requirements when working professionally. This section of this article is going to focus on rigging fixtures, if you’re interested in rigging up trussing or lighting bars look a little further down.
Rigging Fixtures:
This may seem like a very simple and easy thing to do, but is often made a considerable amount harder than it needs to be. The important thing here is preparation. We all know the saying ‘Prior preparation and planning prevent p**s poor performance’ though it often seems the case that people ignore this basic principle and go straight into things all guns blazing. Therefore my first point to make when rigging safely is Preparation is key. The idea behind this is that you should do as much as possible to prepare the fixture on the ground as you can, this is a far safer environment than at height and of course applies much more to smaller venues where flying lighting bars in isn’t an option. Some things you should consider when preparing a fixture are:
This guide is not going to go into the safe use of ladders as it is a recommendation that all persons using ladders should be suitably trained to do so. In a professional environment it is usually a requirement that you are ladder trained and have an accredited qualification to prove this. If you’re looking for more information on this check out The Ladder Association: www.ladderassociation.org.uk.
Please remember this is not an exhaustive guide and in not a substitute for professional training. Neither the author or The Technicians Toolbox can be held liable for any damage, injury or other harm caused to persons or equipment as a result of following this guide.
Rigging Truss or Bars:
When first entering a venue it is often a requirement that you will need to rig up trussing in order to hang lights from, this is especially the case when working with touring productions or at temporary venues. Though rigging fixtures can be dangerous, the majority of harm done to the public or crew at events is through truss collapses. Therefore it is extremely important to ensure that all of the relevant safety precautions are followed and that work is carried out by trained riggers working in a safe and structured work place.
In the UK riggers will need to be certified before being allowed to rig trussing for public performance, unless under direct supervision of someone who is qualified. However it is a recommendation that even if you are only ever going to be doing small amounts of rigging you should be trained.
Truss: Preparation:
When rigging truss the first thing you will need to do is determine the type of truss required to do the job. This is because different trusses have different weight ratings and so ensuring that you have a truss run with and appropriate SWL is always key. When determining this it is important to check the load requirements of the job carefully and determine the exact load on any truss run. Then make sure that the truss is capable of lifting the required loads, you will also want to build a level of safety into this and so no truss should ever be loaded to its maximum SWL. For example if a truss can hold 500kg, it would be good practice to only load 400kg on to it. It’s vital you make sure you fully understand the loading figures when building a truss system and don’t be afraid to ask if you are unsure.
You will also need to take into account the SWL of the venues rigging points when determining the type of truss you want to use. When calculating the total load on rigging points it is extremely important to consider the weight of chain hoists and motors as well as cable and distro packs, as these are all things that will add weight to your truss. If you are in a position where you will be required to calculate weight distribution amongst rigging points, then you should consider taking an advanced rigging course and to determine the SWL of rigging points you will need a certified structural engineer.
Travel and Handling:
When used within its designated loading parameters trussing is generally a relatively maintenance free item and when handled with care it can have a very long operating life. There are a few steps to follow in ensuring that you trussing is kept in the best possible condition, one of which being you should try not to drop your truss as it will cause the ends to become deformed. If this happens then the truss will not operate properly as it may not slot together correctly or sit flush at the joints, this may lead to difficulty when inserting truss pins to securely attach pieces of truss together.
When possible store truss upright. If truss is to be stored horizontally it is advisable to stack the truss with pieces of wood (or such like) in between each section as this will prevent the ends from coming in to contact and becoming deformed. Furthermore it is never a good idea to drag one piece of trussing over another as this can cause damage to both the connectors and the diagonals. In addition to this ensure that when you are loading or unloading there are sufficient people present to ensure that the truss is handled properly and so prevent damage to the ends. Additionally there are recommendations for the weights that an individual should carry without harm. It is important to stick to those limits as they can help prevent injury in the workplace.
Inspecting Trussing before use:
Prior to using a rigging a truss in a new venue there are some things that we need to look out for to ensure that the truss is safe to use. Do not use a piece of truss if:
Rigging:
Rigging of trussing, as I’ve said many times, should only be done by people who are trained and familiar with the use of aluminium truss. See above for recommended training centres. When rigging trussing working as a team is very important. Between you, you should divide jobs and then use a buddy system to check that they have been completed to a high standard and so safety will not be compromised. For example one person should be responsible for ensuring that all of the nuts and bolts are done up correctly. Another could be in charge of rigging all of the flying points to the house rigging points as so to ensure that there is no danger of them being overloaded, due to this involving a lot of work this person will likely wish to work with someone. Other jobs should be divided out, such as rigging lights to the truss and so on but it is very important to have a person in charge of the rigging job, this individual should be responsible for the whole rigging job.
Joining trussing together – to add one bit of truss to another you should first of all put the eggs in the truss, then you should add the pins through the hole in the truss and through the egg connecting to two bits of truss together and securing them. Finally you should add the R clips through the pins to stop them from slipping out. When joining trussing it is important to ensure that all of the diagonals form a continuous pattern, as shown at bottom of page:
Trussing can be suspended in a number of different ways, for example trussing can be rigged vertically out of base plate and then have cross sections connecting the totems. It can also be used to form interesting shapes and structures at ground level, but most commonly it is used to fly lights or PA systems. In order to do this it will need to be attached to a flying point via a chain hoist.
One of the most common ways of attaching trussing to a chain hoist is through the use of a sling. There are a number of ways in which a sling can be attached to a piece of truss, most of which are highlighted below (at bottom of page!):
When considering the maximum load you can place on a truss you will also want to consider the SWL of the sling and all of the shackles that you will be using. Remember that your system is only as strong as your weakest link and so even if you have everything rated to 500kg but you only have 300kg shackles you can only load a maximum of 300kg on to that section, and then reduce this figure a little to add the safety window that was discussed earlier.
On the note of the SWL’s of equipment, it is also important to ensure that all of your rigging equipment complies with relevant safety standards. Venue specific rigging equipment requirements are available from the venue in question, though here is a really good example of how a venue would expect rigging operations to be carried out and the rules relating to what equipment can and can’t be used for what. This is from the Royal Albert Hall and so is very comprehensive and can seem confusing at points though it is still interesting to read, most venues will produce a very similar document:
http://www.royalalberthall.com/uploadedFiles/About_The_Hall/assets/royal_albert_hall_rigging_code_of_practice.pdf
I am not going to go in to much more detail on the specifics of how to rig a truss system, as this is a subject that needs to be covered in much more detail by a trained instructor on a training course, though I am going to highlight this document: http://www.aeo.org.uk/files/naa_rigging_guidance.pdf. It has been produced by the National Arena’s Association and provides much more comprehensive rigging advice for larger venues than I can offer in this document and is much more suited to those who work in rigging professionally, though do note it is specific to the UK and so for other parts of the world you will need to consult relevant local publications.
As you may have noticed I have not talked about up-rigging and working on grids to rig chain hoists or motors in this document, though these are highlighted in the above link and, you guessed it, only trained individuals should undertake these tasks.
Please remember in whatever you’re doing regarding rigging safety is always the number one priority and if you wouldn’t let you mother or child stand underneath what you’ve rigged then you need to be doing something differently. Always think about what could happen if you cut corners and if you see something wrong put it right as ‘safety doesn’t happen by accident’ .
The Technician's Toolbox
Rigging Fixtures:
This may seem like a very simple and easy thing to do, but is often made a considerable amount harder than it needs to be. The important thing here is preparation. We all know the saying ‘Prior preparation and planning prevent p**s poor performance’ though it often seems the case that people ignore this basic principle and go straight into things all guns blazing. Therefore my first point to make when rigging safely is Preparation is key. The idea behind this is that you should do as much as possible to prepare the fixture on the ground as you can, this is a far safer environment than at height and of course applies much more to smaller venues where flying lighting bars in isn’t an option. Some things you should consider when preparing a fixture are:
- Does it work? This is much easier to test on conventional fixtures as you can just plug it into a dimmer pack and run the test circuit, but if you get the option with intelligent fixtures just set up an IEC or PowerCon cable and check to see that the fixture starts up. In an arena setting this may not be practical as you are likely to have lots of fixtures, though it is a good idea if this is the first time you are taking delivery from a hire company. This will hopefully save you a lot of time as if you rig a fixture and then realise the lamp’s blown it is really easy to swap it out for a spare fixture or change the lamp at ground level, this is also much safer than attempting to change a lamp at height.
- Does it have the right gel? It’s much easier, and safer, to gel lights at floor level than at height. A good lighting plot will have the gels that the designer has requested on it and so it is easy to identify which gel you need to use.
- Is there a safety cable attached? If you take nothing else from this guide let it be this: SAFETY CABLES ARE VITAL. The safety cable is the last line of defence against a fixture falling. Safety cables are used to prevent serious injury and therefore are an industry standard requirement. All fixtures must be rigged with a safety cable otherwise you could be liable for any damage/injuries however this does not mean if you add a safety that you are not liable for any damages/injuries. It should be the first thing to go on once the clamp has been secured to the bar or truss and so it will be easier to attach it to the fixture before it is either hoisted up or carried up the ladder. It is also important to check the weight rating of the safety cable against the weight of the fixture as some have different safe working loads.
- Is the clamp ready? You would be surprised at the number of people who stand at the top of ladders or next to lighting bars faffing around unscrewing the wing nut on the clamp. You will also want to consider if the clamp is securely attached to the fixture. This is especially important when working with moving lights as they often weigh a lot more.
- Is it the right fixture? It sounds silly but it will cost you a lot more time if it is than a quick glance at your lighting plot will. This is also an important safety factor as if you rig the wrong fixture’s you may risk overloading your lighting bars which has potential for catastrophic consequences ensue. It is a good idea to lay out all of your fixtures on the stage or auditorium floor to the designers plot. This way you can be sure that you are rigging not only what they have asked for, but what it is safe to put in the air.
This guide is not going to go into the safe use of ladders as it is a recommendation that all persons using ladders should be suitably trained to do so. In a professional environment it is usually a requirement that you are ladder trained and have an accredited qualification to prove this. If you’re looking for more information on this check out The Ladder Association: www.ladderassociation.org.uk.
Please remember this is not an exhaustive guide and in not a substitute for professional training. Neither the author or The Technicians Toolbox can be held liable for any damage, injury or other harm caused to persons or equipment as a result of following this guide.
Rigging Truss or Bars:
When first entering a venue it is often a requirement that you will need to rig up trussing in order to hang lights from, this is especially the case when working with touring productions or at temporary venues. Though rigging fixtures can be dangerous, the majority of harm done to the public or crew at events is through truss collapses. Therefore it is extremely important to ensure that all of the relevant safety precautions are followed and that work is carried out by trained riggers working in a safe and structured work place.
In the UK riggers will need to be certified before being allowed to rig trussing for public performance, unless under direct supervision of someone who is qualified. However it is a recommendation that even if you are only ever going to be doing small amounts of rigging you should be trained.
Truss: Preparation:
When rigging truss the first thing you will need to do is determine the type of truss required to do the job. This is because different trusses have different weight ratings and so ensuring that you have a truss run with and appropriate SWL is always key. When determining this it is important to check the load requirements of the job carefully and determine the exact load on any truss run. Then make sure that the truss is capable of lifting the required loads, you will also want to build a level of safety into this and so no truss should ever be loaded to its maximum SWL. For example if a truss can hold 500kg, it would be good practice to only load 400kg on to it. It’s vital you make sure you fully understand the loading figures when building a truss system and don’t be afraid to ask if you are unsure.
You will also need to take into account the SWL of the venues rigging points when determining the type of truss you want to use. When calculating the total load on rigging points it is extremely important to consider the weight of chain hoists and motors as well as cable and distro packs, as these are all things that will add weight to your truss. If you are in a position where you will be required to calculate weight distribution amongst rigging points, then you should consider taking an advanced rigging course and to determine the SWL of rigging points you will need a certified structural engineer.
Travel and Handling:
When used within its designated loading parameters trussing is generally a relatively maintenance free item and when handled with care it can have a very long operating life. There are a few steps to follow in ensuring that you trussing is kept in the best possible condition, one of which being you should try not to drop your truss as it will cause the ends to become deformed. If this happens then the truss will not operate properly as it may not slot together correctly or sit flush at the joints, this may lead to difficulty when inserting truss pins to securely attach pieces of truss together.
When possible store truss upright. If truss is to be stored horizontally it is advisable to stack the truss with pieces of wood (or such like) in between each section as this will prevent the ends from coming in to contact and becoming deformed. Furthermore it is never a good idea to drag one piece of trussing over another as this can cause damage to both the connectors and the diagonals. In addition to this ensure that when you are loading or unloading there are sufficient people present to ensure that the truss is handled properly and so prevent damage to the ends. Additionally there are recommendations for the weights that an individual should carry without harm. It is important to stick to those limits as they can help prevent injury in the workplace.
Inspecting Trussing before use:
Prior to using a rigging a truss in a new venue there are some things that we need to look out for to ensure that the truss is safe to use. Do not use a piece of truss if:
- There are any cracks in the welds.
- Any of the Camloc plates are bent.
- High tensile M16 nuts & bolts are worn. Replace as necessary (Bear in mind that every time any nut & bolt is used some thread is lost).
- There are any dents on the main tubes or diagonals.
- The truss is badly chewed by wing nuts/bolts.
- The truss section is bent or sagging in the middle. (This does not apply to deliberately shaped trussing.
- You have any other reason to doubt the structural integrity of the truss. If in doubt ask someone more knowledgeable.
Rigging:
Rigging of trussing, as I’ve said many times, should only be done by people who are trained and familiar with the use of aluminium truss. See above for recommended training centres. When rigging trussing working as a team is very important. Between you, you should divide jobs and then use a buddy system to check that they have been completed to a high standard and so safety will not be compromised. For example one person should be responsible for ensuring that all of the nuts and bolts are done up correctly. Another could be in charge of rigging all of the flying points to the house rigging points as so to ensure that there is no danger of them being overloaded, due to this involving a lot of work this person will likely wish to work with someone. Other jobs should be divided out, such as rigging lights to the truss and so on but it is very important to have a person in charge of the rigging job, this individual should be responsible for the whole rigging job.
Joining trussing together – to add one bit of truss to another you should first of all put the eggs in the truss, then you should add the pins through the hole in the truss and through the egg connecting to two bits of truss together and securing them. Finally you should add the R clips through the pins to stop them from slipping out. When joining trussing it is important to ensure that all of the diagonals form a continuous pattern, as shown at bottom of page:
Trussing can be suspended in a number of different ways, for example trussing can be rigged vertically out of base plate and then have cross sections connecting the totems. It can also be used to form interesting shapes and structures at ground level, but most commonly it is used to fly lights or PA systems. In order to do this it will need to be attached to a flying point via a chain hoist.
One of the most common ways of attaching trussing to a chain hoist is through the use of a sling. There are a number of ways in which a sling can be attached to a piece of truss, most of which are highlighted below (at bottom of page!):
When considering the maximum load you can place on a truss you will also want to consider the SWL of the sling and all of the shackles that you will be using. Remember that your system is only as strong as your weakest link and so even if you have everything rated to 500kg but you only have 300kg shackles you can only load a maximum of 300kg on to that section, and then reduce this figure a little to add the safety window that was discussed earlier.
On the note of the SWL’s of equipment, it is also important to ensure that all of your rigging equipment complies with relevant safety standards. Venue specific rigging equipment requirements are available from the venue in question, though here is a really good example of how a venue would expect rigging operations to be carried out and the rules relating to what equipment can and can’t be used for what. This is from the Royal Albert Hall and so is very comprehensive and can seem confusing at points though it is still interesting to read, most venues will produce a very similar document:
http://www.royalalberthall.com/uploadedFiles/About_The_Hall/assets/royal_albert_hall_rigging_code_of_practice.pdf
I am not going to go in to much more detail on the specifics of how to rig a truss system, as this is a subject that needs to be covered in much more detail by a trained instructor on a training course, though I am going to highlight this document: http://www.aeo.org.uk/files/naa_rigging_guidance.pdf. It has been produced by the National Arena’s Association and provides much more comprehensive rigging advice for larger venues than I can offer in this document and is much more suited to those who work in rigging professionally, though do note it is specific to the UK and so for other parts of the world you will need to consult relevant local publications.
As you may have noticed I have not talked about up-rigging and working on grids to rig chain hoists or motors in this document, though these are highlighted in the above link and, you guessed it, only trained individuals should undertake these tasks.
Please remember in whatever you’re doing regarding rigging safety is always the number one priority and if you wouldn’t let you mother or child stand underneath what you’ve rigged then you need to be doing something differently. Always think about what could happen if you cut corners and if you see something wrong put it right as ‘safety doesn’t happen by accident’ .
The Technician's Toolbox
How to join two pieces of truss!
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How to add a sling to truss!
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