When RIGS FLY: Rigging and Safety Regulations

In Uncategorizedby tfwm

An ETCP Certified rigger (one of only 13 in North America) tells you how, with the right planning and instruction, your church can escape a whole heap of rubble

The catch broke on the small winch just as I was reaching to tie the rope that had been the “safety” preventing the handle from spinning. The handle became a blur as the lighting batten freewheeled towards the floor. It beat holes in my shirt sleeve as I jerked away; three of them on my elbow and two more on the forearm. My left arm went numb and I was sure it would fall off if I didn’t hold it in place with my right hand. I heard my teacher scream as the batten hit the end of the wire ropes. The shock ripped the toggle bolts out of the cinder block wall and the contraption zipped past my ear to land in a web of conduit pipes as the batten, loaded with PAR bulbs, crashed into the floor. This was my first experience with any kind of stage rigging.

This happened 38 years ago when I was still in high school. I remember it clearly because not only was it the cause of my first trip to the emergency room, the experience also launched me into an Entertainment Industry career with special attention towards rigging.

The Lowest Bidder
Why did this accident happen? How could something in a building less than four years old fail in this manner? Consider that this building was built in the 1960s, yet even so, some of the same circumstances still exist in many theatres and houses of worship today.

Where to start? How about with the lowest bidder? Any group of people responsible for building a building does the prudent thing by watching costs. The low bidder nearly always gets the job. Rarely do we see a board or committee that looks for the lowest and BEST bidder. When a building includes a stage, does the builder know anything about stage rigging or the special needs of lighting, audio, and projection used for video or live presentation?

In the case of my high school, the electrical contractor was responsible for the installation of the lighting batten over the stage. The contractor attached a circuit raceway to a batten made by screwing lengths of pipe together with threaded couplers, then used 1/4” wire rope with a fibre center to lift it. The wire ropes were run through 4” pulleys and gathered at a clew made by drilling holes in a piece of angle iron. Each wire rope was terminated with one U bolt clamp purchased at the local hardware store. One wire rope ran from the clew to the winch. The winch was the type found on boat trailers and used to slide a boat out of the water onto the trailer. As mentioned above, it was anchored to cinder blocks with toggle bolts. If the winch had a rating for a safe working load, no one knew what it was. No one knew how much the batten loaded with lights weighed either. The winch would click loudly as the handle was cranked and the catch would ratchet over the gear teeth on the sprocket. It was supposed to hold tension if you let go of the handle. It was never designed for the stresses being applied, and soon became unreliable. The school custodian that normally cranked it had installed a short length of sash cord to lash the handle to a conduit pipe. You had to untie the rope to turn the handle. The only brake was in the strength of your hands. An untrained volunteer (me) was sent up a ladder to the top of a mechanical space to operate this winch.

Now, let’s go back to see how many weak links there were in my high school system. The first has already been mentioned. The installer had no idea what was really involved in the use of the lighting batten. The weights, stresses, and resultant loads were never considered. The batten was made from water pipe which is acceptable, but the joints were made with the threaded couplers that come with the pipe. The threading process removes about 50% of the metal. This weakens the joint considerably. It is much stronger to use a sleeve inside both pipes at the joint, then weld or bolt it in place.

The fibre core wire rope was flexible and easy to work with, but it also had very little strength and was never intended for overhead lifting. It should have been 6 x19 construction. (6 individual yarns composed of 19 single wires each, all twisted into one wire rope.)

The 4” pulleys had more than one problem: they were purchased at the local hardware store, they were never intended for overhead applications, and they were not big enough.

Rigging standards call for a 30 : 1 D to D ratio. That means the diameter of the pulley should be at least 30 times the diameter of the wire rope. In this case, a 7.5î pulley would be the minimum size for the 1/4î wire rope. This prevents the wire strands from bending too sharply and lessens wear and metal fatigue.

The “U bolt” cable clips used to terminate the wire ropes were inexpensive items, also available at any hardware store. Again, these were never made for hanging things over the heads of people. Most were foreign-made and carried the name of their country of origin. No product testing information could be found on them, nor could it be determined how many of them should have been used at each termination.

In order for wire rope clips to be acceptable for rigging applications, they should be stamped with a product code that allows them to be traced back to the manufacturer who will supply all of the testing information on them. There are two manufacturers that do this: The Crosby Group and Columbus McKinnon. Of course they are more expensive than the ones at the local hardware store, but you will sleep better at night.

The winch, obviously, was never built to be used in this manner. Worse still, it was attached to a cinder block wall with toggle bolts. Neither the bolts nor the cinder blocks had the strength to handle a shock load.

Then there were three huge human failures contributing on the operation side of things. In the first place, an untrained, unsupervised volunteer should never have been allowed to operate the batten. Secondly, the teacher in charge of the production was uneducated about the system. Being the supervisor of the production, she was the “responsible person” standing at the front of the liability line if a civil suit had occurred. Thirdly, (and most importantly) even with all the wrong hardware, the accident could have been avoided if the custodian had declared the winch to be “out of service” and put some sort of lock out on it until a solution could be found. Tying on a rope that could be undone by anyone was asking for trouble.

Standard Practice
None of the above fits into the rigging guidelines we have today. And nothing gets the attention of a Board of Directors like a pending law suit. It was similar situations involving accidents, injuries, and even a few deaths, that resulted in law suits and spawned the rigging awareness in the 1980s. The United States Institute for Theatre Technology (USITT) wrote and published their recommendations for stage rigging practices during this time. Rigging workshops and seminars began to be held by recognized experts in the field. Many experienced technical people in the business discovered that not only had they been doing things in an unsafe manner, they were also legally liable.

In recent years, the Entertainment Services and Technology Association (ESTA) has undertaken the task of writing Theatrical Rigging Standards for acceptance by the American National Standards Institute (ANSI). ESTA also launched the Entertainment Technician Certification Program (ETCP). This program recognizes individuals that complete the voluntary testing process demonstrating certain knowledge, skills, and abilities.

Today, several books have been written specifically about rigging for the industry. If you can only afford to purchase one book on the subject, I recommend the Stage Rigging Handbook by Jay O. Glerum. It is currently in the third edition and available from Southern Illinois University Press. It covers the basics of hardware and wire rope as well as load calculations, and procedures for training, safety, and maintenance.

How does all this relate to a house of worship? The technological revolution has inspired many venues that, in the past, were content with some drapes and a few lights on a switch, to want more of everything. More lights, more audio, more video. Technology has become part of everything we do. The days of singing hymns along with a piano are becoming a thing of the past.

Amplified music with a hanging speaker system is the new norm. Specialized lighting for the platform area requires theatrical lighting fixtures to be hung overhead. Video has become commonplace, with many churches wanting image magnification and/or power point screens. Even small churches of less than 200 seats are incorporating one or more of these elements. Many times the churches will add them as funds become available.

Unfortunately, these elements are often installed by a local vendor or by house staff who have had little to no experience or training. The lighting, audio, and video equipment is all adapted from the entertainment industry for use in churches, and so it all requires the same rigging hardware and skills to hang and keep safely overhead as in any other application.

As the Project Manager for a consulting and design firm I have witnessed, first hand, this increase in technology in churches across the country. Sometimes we are hired to help design theatrical elements for a new facility before it is built. Other times we are brought in to upgrade or to “fix” existing problems. Many of the things I find that need “fixing” often remind me of my high school stage— installations done by low bidders who have very little knowledge or skill related to rigging. Or, I find installations that have been done by house staff, either paid or volunteer. The common explanation is: “We needed to hang (such and such) for a special event. We couldn’t afford to hire a rigger so we did it ourselves. We left the hardware in place in case we needed to do it again.” Like the labor, the hardware was done as cheaply as possible and not rated for overhead use or applied in the correct manner.

The Wrong Way
While surveying one church, I found several forged eye bolts hanging below the plaster ceiling of the platform area. The staff told me they were first used to hang special scenic elements for an Easter program. They had left them in place and added others over the years as needed. These were large eye bolts with a 1/2” diameter shaft. I felt very good about them until I got above the ceiling to see what they were attached to.

The staff had the best of intentions, but lacked the proper knowledge for correct application. Some of the eye bolts had been in place for several years. The building steel was adequate for the job and the eye bolts were good, but everything in between was either the wrong hardware or it was applied unsafely. When hanging something over people’s heads, there is no such thing as too much caution. If it can’t be done safely, don’t do it. In the case of this church, it is true that some of the gear had been in place for years without failing. My response to that is: All it takes is once!

When planning to rig anything, I always start with the building structure. What do we have to hang from? Is the support steel strong enough to hold what we are hanging as well as the roof? How much more can it hold? This is extremely important in areas where snow and ice can build up. Earthquake zones have limiting factors as well. Checking with the structural engineer for the building is very important. Once the determination is made as to how much the building can support, the proper choices can be made for the installation. If you are not trained in the correct hardware to use, find someone that is. Using the wrong stuff can be dangerous.

Frequently, the roof structure can support added weight, but single point loads on individual members are too much. This can be resolved by attaching spanner beams across several members to help distribute the load. A good example of this can be seen on page 72.

Also shown are other examples of good rigging practices. First, the wire ropes are terminated with thimbles and copper swages. The thimbles hold the wire rope in a gentle, rounded turn. The swages, if properly applied, are rated as strong as the wire rope. Next, the turnbuckles and shackles are maused with stiff wire. This means that they can not work loose over time due to vibrations from motors or music. A steel safety cable is looped through the thimble and over the spanner beam. These support self climbing trusses that hang over the congregation in a large sanctuary. There is no such thing as too many safety precautions.

Do It Yourself?
Anyone with a little bit of ingenuity can figure out how to rig something overhead. The questions are: Should they? Do they know the liability they are assuming by doing the rigging? Does their supervisor or the church administration know the exposure they will have if something falls? If not, don’t proceed! Call someone that is qualified. If you have trouble finding someone, contact ESTA for a list of certified riggers.

One final area of rigging needs to be addressed particularly for houses of worship: Flying people. I get calls every year from churches that want to stage ascensions or to fly angels. Of course, they want to do it themselves with out spending a lot of money. My answer is to always refer them to one of the companies that specializes in flying people. They are the inventors of the hardware used in that craft. They have the knowledge and the skills to install it safely. Most importantly, they are insured for it. I have worked with most of them. I have helped install and operate their equipment and I understand how it works. Would I attempt to do it on my own? Not on your life!

The show does not have to go on. The show must go on only if it can be done safely.