Rigging Runaways

[Erich Friend]

Probably one of the most terrifying things you can hear when working on an Arena Show or Theatre Stage is someone calling “HEADS!”  Why is this so scary?  Because it means that something is falling from somewhere.   You don’t know what it is, how heavy it is, and you don’t know where it’s coming from (other than ‘above’).  So, what can you do to minimize the risk?

• Hard Hats are a good idea, and in many places they are considered mandatory PPE (Personal Protective Equipment).  They’ll save your bacon if the object is fairly lightweight or not falling too fast (or far - the higher it falls from, the faster it'll be moving), but they may not save you from a falling counterweight brick.
  
• Keep the Stage Clear whenever there are rigging operations taking place.  If you aren’t under the work piece (batten, worker on the grid, truss, loading gallery, etc.), then you are less likely to be in the path of a dropped object (wrench, shackle, counterweight, etc.).
  
  
• Don’t Look Up.  Run first & fast, look to see what the ‘problem’ is later (you shouldn’t stop running until you are under cover of some protective structure or you hear the ‘problem’ hit the floor).  The best way to get your face smashed is to dawdle-around and look up to see what may be heading your way.  You don’t want to use your face to catch a screwdriver or a counterweight.
  
  
• Know your Exit Path so you can move to the safest place quickly.  If you are the fly man at the Locking Rail and you have a arbor runaway, or hear HEADS! from your loading crew, then run away sideways (on an elevated Locking Rail Bridge), or at a 45 degree angle from the line set (when on the stage level).  If you run away perpendicular to the Locking Rail and onto the stage, then you may be running directly into the path of a rapidly descending batten.

For those of you that may be the cause or instigator of the problem:

• Keep the Stage Clear whenever there are rigging operations or overhead work taking place.  Have your ground crew clear the work area and make sure that no one enters the area under the workers, loudspeakers, battens, or trusses that are being moved.  Post sentries and/or set-up barricades, if possible.
  
  
• Keep the Area Under the Fly Rail Clear (for counterweight operations) so that when a dropped counterweight comes boinging down, bouncing off the ropes, cables, structure, air ducts, and other fly gallery items, it doesn’t strike anyone.  A counterweight is a very heavy and has a completely unpredictable trajectory unless it is falling through a clear space.
  
  
• Empty Your Pockets.  Loose items like cell phones, coins, pens, rings, etc.  These items don’t need to go to the grid with you.  Leave them at ground level.
  
  
• Lash & Lanyard Loose Items.  Wrenches, Radios, Flashlights, Cameras, Tape Measures, and other tools should all have a means to tie them to your person so that when (not if) you lose your grip - they will only fall a few feet and can be recovered.  Tool Belts and Pouches are good for hauling stuff around, but they don’t do any good for hanging on to them once they are deployed for use.  Eyeglasses and Hard Hats should have retention straps so they will not fall off.
  
  
• Remove ANY and ALL loose items from the Grid Iron deck.  Clean-up after yourself and anyone else that left stuff behind (this includes the original constructions crew, service workers, and people that shouldn’t have been up there anyway).

At the Fly Rail

One of the key parts of a counterweighted rigging system that can save you from a runaway line set is the proper use of the Rope Lock.  Many older systems have products that were fabricated from cast iron parts, and they are subject to cracking, and ultimately, failing under load.

 

The Rope Lock is only intended to hold a minimal amount of load imbalance.  It should not be expected to prevent the movement of a Counterweight Arbor (carriage) that is significantly out of balance.  +/-50 Pounds (~20 Kg) is the maximum that sets should be allowed to be out of balance – and this is enough weight to allow a line set to runaway should the operator(s) lose their grip.

 

Modern Rope Locks are made from welded and formed steel plates and are designed to allow the Facility Manager or Fly Master to secure them so that they cannot be operated without authorization.  The handle on the Rope Lock can be barred from movement with a padlock, key lock, or wire rope cable lock so that unauthorized users cannot move the line sets.

Master Lock makes a cable device (S806CBL) that can be used to Lock-Out-Tag-Out multiple Rope Locks at a time.  It is available in a variety of lengths.

 

 

 

 

Good examples of modern Rope Locks are:

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Tiffin Scenic Studios                 H&H Specialties            Thern Stage Equipment           JR Clancy

 

The Tiffin Restrictor has an indicator to show you if the hauling line is tensioned 'Stage Heavy' or' 'Arbor Heavy'.

The H&H device can be locked open or closed, and they have an optional Lock-Out-Tag-Out accessory to facilitate multiple locks by different departments.

The Thern device is very smooth operating and costs no more than a 'standard' rope lock.  It can be locked open or closed, and has a push-button to release it in stead of a ring around the rope and handle.

The JR Clancy device won't allow you to unlock the rope unless the hauling line has little or no tension on it.

 

THERE ARE TWO TYPES OF RUNAWAY RIGGING SCENARIOS

Stage Heavy:

This can happen when the counterweights have been removed from the Arbor before the batten load has been removed.  This is a common occurrence when the stage crew is understaffed and the loading crew may be also doing the stage crew’s work.  This is a very good reason to make sure that you have sufficient staffing for your show load-in and strike operations.

 

What Happens:  The Counterweight Arbor runs up to the Head Blocks (or head beams) and stops suddenly at the top.  If the counterweight bricks are not secured by the Weight Locking Rings, then they can be jostled loose by the sudden stop (the bricks try to continue upwards due to inertia) and then fall back to the stage floor below (HEADS!).  This is called a ‘Top Crash’ – yes, people have died when struck from falling counterweight bricks.  The Batten and its payload descend rapidly toward the stage floor.  Depending upon the strength of the rigging components, and the weight that is involved, this can possibly rip the batten and payload away from the lift lines and destroy them (and anyone in their path, too – yes, people have died when struck from falling battens.)

 

If the batten and/or its payload become disconnected from the lift lines, then the system reverts to an Arbor Heavy condition and the following situation can occur.  This results in a Top Crash and a Bottom Crash.

 

Side effects:  If you don’t have the presence of mind to let go of the hauling rope when the arbor rises, you can have your hands jammed into the top of the rope lock and get some serious rope burns and pinched flesh.

 

Arbor Heavy:

This can happen when the batten load has been removed before the counterweights have been removed from the Arbor.  This is a common occurrence when the stage crew is overstaffed and the weight loading crew is trying to keep-up with them as the stage crew strips a batten.  This is a very good reason to make sure that your Fly Master is monitoring the rate at which workers are removing drops, lights, or other scenery as a show is struck.

What Happens:  The Counterweight Arbor runs down to the Take-up Blocks (or Lower Arbor Stop) and stops suddenly at the bottom.  This is called a ‘Bottom Crash’.  It can bend or break the Lower Arbor Stop Rail (see above).  The Batten and its payload ascend rapidly toward the grid iron deck.  If the Arbor travels significantly beyond the Lower Arbor Stop Rail, then it can jamb the Batten into the Grid Iron Deck, Loft Well Channels, Loft Blocks, and or Fire Sprinkler Pipes.  Depending upon the strength of the rigging components, and the weight that is involved, this can possibly rip the batten and payload away from the lift lines, which can release the Batten and its payload to fall back to the stage floor (and crush anyone in their path – yes, people have died when struck from falling battens.)

Side effects:  If you don’t have the presence of mind to let go of the hauling rope when the arbor drops, you can be pulled up off of the floor and in short-order smash your head into the bottom of the Loading Gallery above.  This will usually stun you so that you will let go of the rope (not to mention the cranium bashing that will occur of you aren’t wearing a Hard Hat) and fall back to the Locking Rail.  This can result in broken legs, and other contusions depending upon how you land and what other items might be on the floor around the scene of the crime.

 

Exciting!  You DON’T want to be there.

[Candyce Iseminger]

Something I noticed... In our venue we don't yell "HEADS" when something is hurtling towards deck, we yell "INCOMING"... for what little we use it, I've notice that "HEADS" leads people to look up to see what they should watch out for, while "INCOMING" seems to get people to move rather then wonder what's going to hit their head... We always make it a point to teach new hands that "INCOMING" is the proper term, we don't need to know what or where, we just need to know that we need to get off the deck.

[Rich Dionne]

Great post, Erich! A few years ago, we had a situation where a brick was dropped from the weight rail, and plummeted some 60+ feet to fly well. (Our lower kick blocks are actually in the basement, below the locking rail, leaving a sizable well offstage of the locking rail.) Fortunately, the trajectory of the brick remained relatively straight, and no one was hurt--though there's a sizable chunk of the concrete floor broken off.

Since that time, we've instituted a much more stringent training and certification program, and instill in all of our students that no one does anything during fly rigging operations without the explicit direction of the fly operator. This helps to ensure that inadvertent arbor or pipe heavy situations don't happen, because one person is directing all of the work on either end of the lift lines. Fly systems are common enough that we sometimes forget how dangerous they are, and train students "on the fly" (excuse the pun). This is not the best option: we need to be sure they are trained in the forces and dangers involved and in specific processes and techniques before they ever get near the lock rail, to ensure they don't hurt themselves or others.