Thursday, August 11, 2011

Fall Protection with Trolley Beams

Rigid Lifelines contributed this article as a guest blogger from their Fall Protection Blog.  This fall protection equipment company provides fall restraint and fall arrest systems that provide fall safety solutions to a variety of different industries.

The performing arts industry, like many other industries, entails many different fall hazards.  Performers, stagehands, lighting and sound technicians, set decorators, and other workers are frequently confronted with fall hazards.  Productions may place performers on elevated platforms, and frequently support crews must reach-out over guard rails or lean over the edges of platforms to access work pieces.  Each of these unique challenges demand that specific fall prevention solutions must be designed by a certified fall protection professional.

Fortunately, there are several ways to address such hazards.  Passive fall protection, such as guard rails on a catwalk, may be sufficient for workers who require ceiling access, for example, to install or adjust lighting or sound equipment. Frequently, however, catwalks and structural I-beams are not fully protected, and workers are required to be tied-off when accessing such areas, which may be as high as 100 or more feet above the ground in large venues.  In that case, the OSHA 4-foot general industry rule requires that they be protected, so some type of a fall protection arrangement is necessary.

As with many other industries, the fall protection solution depends on the job.  If workers are going to traverse a wider lateral distance, like along a roof beam or loading gallery, then they are probably going to want a system where fall protection is provided along a linear path.  This could be achieved with an active system that utilizes a safety harness and lanyard attached to a cable or some type of rail or I-beam system.  In such a system, the cable, track, or beam is attached to the existing ceiling support structure.  When attached to the fall protection system, workers can move along with a trolley, allowing them to work relatively unimpeded.  In the event of a fall, the anchor system is designed to actively arrest their free-fall with the shock absorption lanyard and fall protection harness.

  • A safety cable that is stretched tight between two points will inherently add some extra ‘give’ to the system, so this must be accounted-for when determining how far the system will allow the worker to fall before coming to a full stop.  This extra travel may also affect the rescue procedures need to recover a fallen worker.

    • A rigid track type system gives very little, so it can provide a more robust protection.
    Examples of the Rigid Lifelines Fall Arresting Track profiles are shown at left.  The single track is for short spans, the truss-type single track is for longer spans, and the dual track is designed to allow two workers to pass each-other without having to trade fall arrest lines.  NOTE:  This is very special load-rated track and it is NOT the same thing as curtain track used in the theatre.  Do NOT attempt to use theatrical curtain track and scenery carriers for fall protection purposes.

    In scenarios where the work area is limited and the worker does not to move about very much, a single point attachment can be used to allow a worker to hook-in with their restraint lanyard to a designated point in the ceiling (using a structural eye-bolt or some type of a load-rated beam clamp).  In this case, the worker’s movement is limited, per OSHA, to 30° off of plumb, but they are still protected in the event of a freefall.  The 30° limitation is to prevent the worker from swinging too far in a pendulum motion where they might swing back and smash into a wall or other protruding hazard.
    Worker attaching to a designated fall protection attachment point (Courtesy of RUD)
    Depending on the activities needed by the show, performers may require a customized fall prevention or fall arresting system.  If the performer(s) are being suspended from a special performance flying system, then they may have a back-up fall arrest system to protect them should the primary fly system fail and place them in a free-fall condition during the performance.  It is very common to see aerialists tied-off to self retracting life lines in Cirque de Soleil shows.

    In other scenarios, the performers may have to work at the edge of a high platform.  If they are moving about, then they may require a dynamic system with retractile reels that keep the slack in the line to a minimum.  One popular Broadway show that has received recent media attention is Spiderman.  In that show, the performer runs out on a cantilevered platform and looks over the edge into an abyss below (the orchestra pit some 30 feet down).  You can see the fall protection lanyard trailing behind the performer, but the audience doesn’t seem to focus on it.  This system is designed to be a fall restraint system (one that never allows the performer to actually fall).  This particular system failed during one of the early shows because it had not been properly inspected and the fall restraint line was allowed to become abraded.  When loaded by the running actor, it snapped and the performer fell into the orchestra pit and was injured.
    Other fall restraint systems are simpler, they use a fall restraint lanyard that is a fixed length.  It too, prevents the worker / performer from getting in the situation where an actual fall is possible.  These are common on loading galleries ad when working leaning out over a balcony railing.

    Where more maneuverability is needed and the worker must be able to place themselves in a situation where they could actually fall, then a shock absorbing lanyard or an automatically retracting self-locking fall arrest device must be used.

    Automatically retracting self-locking fall arrest device
    (Courtesy of Rigid Lifelines)

    The typical theatrical fall protection focus, however, is on systems designed for workers who will be working in a potential fall hazard area — such as workers who must adjust lighting equipment at height or climb about on fixed or portable trusses.  Common locations for Fall Protection requirements in the theatre are:
    • Balcony Railing Lighting Bars
    • Tormentor Boom Lighting Pipes
    • Scissors Lifts and Boom Arm Lifts
    • Weight Loading Gallery Rails
    • Open Beams and Trusses
    • Fixed Vertical Ladders (with and without cages)
    • Roll-up ladders (like are used to access concert trusses)
    • Upper level storage areas where there can be open sections of the railing
    • Follow Spotlight Platforms
    • Elevated Paint Bridges

    Example of an overhead trolley for attachment
    of fall protection equipment.
    (Courtesy Rigid Lifelines)
    Rigid Lifelines has provide numerous systems to nightclubs and theatrical venues in the Las Vegas area.  Typically, a customer will mount an enclosed track system to the ceiling in a nightclub where lighting/sound equipment needs to be modified or arranged on a regular basis.  In such cases, workers need to access the uppermost areas of often cavernous performance spaces.  With a Rigid Lifelines trolley system, they can hook into the track and walk around on a catwalk or on beams, and in the event of a fall they’re protected by the overhead securement system.  As noted previously, when a cable type system is employed, a worker might fall a significant distance and then find themselves suspended too far below the catwalk / beam to pull themselves back up to safety.  With Rigid track, however, a worker will only fall a few inches, making it easier to recover the worker from the suspension phase.

    Theatrical performances such as “Cirque de Soleil,” in which the performers or support crew must access the ceiling structure, have used Rigid Lifelines track systems to protect workers from a freefall to the lower level.  So while the performing arts industry entails unique fall hazards — sometimes almost intentionally because of the nature of a specific performance — the fall protection solutions are nonetheless similar to those seen in general industry.

    Also note that workers / performers that are using fall protection devices must be trained about donning and using the equipment, checking it for damage, and keep records of use, abuse, and inspections.  Additionally, the workers using the equipment and those supervising them must have a rescue plan worked-out in advance so that a person that has fallen is not left hanging and suffer suspension trauma.  Suspension Trauma occurs when the blood circulation to the extremities is reduced or cut-off due to the tightness of the fall protection harness that is imposed when the worker is hanging by the attachment point(s).

    More information and resources about fall protection systems can be found at:
    Ridgid Lifelines Resources page -

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