Theatre Design & Technology - Winter 1996 - 22

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The R.BI. lighting truss design for the 1995 tour is
a relatively simple one: a rectangle of Thomas 91inch Pre-rigged Truss is outlined 40 feet above the
stage by two 48-foot bolted truss sections going
across stage and two 24-foot bolted truss sections
going up and down stage. Each of the four truss sections that make up the sides of the rectangle are
flOl\11 independently and are not connected at tile
corners. The long cross-stage trusses are flOlm
from three one-ton eM Lodestar chain motors. The
sh0I1er side tnJss sections are flOlm from two oneton motors each. The load at each of tllese motors,
determined by d~l1anlOmeters, ranges between
1000 and 1250 lbs. There are two truss spotlight
positions on the upstage truss and two on each of
the side trusses. (See plan of rig, p. 21) All four of
these lighting trusses are loaded Witll tile bars of
pre-rig par cans along with additional, independently hung ellipsoidals, Moles, truss spots, along
Witll the necessary electrical and control cabling
stnlI1g along the top. Astandard wire rope ladder is
attached to each of the four lighting trusses to provide crew access when irs in the flown position.
For focusing lights and running truss spots,
lighting techs and stagehands need to climb the wire
rope ladder up to the truss and then move laterally
across it. So, given the six foot rule of OSHA (see
Q&A, p. 24), a crew person is exposed to a fall hazard from about tile Sixtll rung of tile ladder, on up to
tile truss, not to mention while he or she is traversing the truss, and while operating the spot. In essence, continuous protection is needed from the
time the stagehand starts up the ladder until he or
she touches back down on the arena floor.
The fall protection system that tours with the
R.E.M. show consists of a vertical componeJ1l for
climbing the ladder and a horizontal componel1l for
traversing the truss.

THE COMMON ELEMENTS
A full-body hamess meeting OSHA and AJ'iSI requirements for fall protection is an integral elemel1l
of this system. As with all full-body harnesses, the
only point of attachment to the fall protection system is the dorsal O-ring located high on the
wearer's back. The Surety Model 809 harness used
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TD&T

on tllis tour also has a chest level O-ring and t\ro llip-level side O-rings intended for
work positioning activities like rappelling. These hamesses are considered part of
tile total fall arrest system and Ct'll1l1ot be replaced by harnesses owned by local
stagehands or local venues.
Attached into tile dorsal O-ring of each harness is a foudoot webbing lanyard
with a integral rip-stitch type shock absorber (Surety model WL-202/RM). Specially
for this fall protection system, Surety and Stage Rigging Inc. have incorporated a
large O-ring begween the webbing and the shock absorber of tile lanyard for the
retractable lifeline to hook into. The shock absorber end of tile lanyard ternlinates
in a locking snaphook that attaches to tile harness dorsal D-ling. The opposite end
of the lanyard ternlinates in a self-locking carabiner. The shock absorber element
in the lanyard is designed to
linlit the Maximum Arresting
R. E. M.
Force (MAF) to under 900 lbs.
Truss Fall
The rigging of tllis fall
protection system requires just
Protection
one modification to tile stanSystem
dard way the trusses are rigged
to the chain motors. Normal
practice is to lead the two legs
of tile polyester roundsling supporting tile truss to a 5/8 inch
anchor shackle and to hook
tilat shackle into the chain motor hook. Because both the
horizontal and vertical lifelines
RETRACTABLE
NOTE.: STAGEHANO
LIFELINE
also need to attach in just below
CLIMBING THE
LADDER HAS A
the motor hook, a 5/8 inch pear
RETRACTABLE
ring is inserted between tile
L1FWNE
CONNECTED TO
truss sling shackle and tile mo[}-RJNG OF THE
tor hook to allow attaching the
LANYARD SHOCK
additional carabiners used to
ABSORBER.
40 FT
anchor the lifelines at that
point.

THE VERTICAL COMPONENT
Just above tile wire rope ladder, a retractable lifeline (Surety Surelock Retractable Lifeline BS-l 01/66) is
anchored to the pear ling attached
into the motor hook by means of an
OSHA-approred self-locking carabiner. (Alternatively, the retractable lifeline can be
dead-hung from the arena steel directly above the wire rope ladder, a procedure
that guarantees that the lifeline hangs clear of the Lighting truss rig as the stagehand
ascends or descends.) Retractable lifelines function very much Like an automobile
seat belt-a spring-loaded spool keeps just enough tension on the lifeline attached

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Table of Contents for the Digital Edition of Theatre Design & Technology - Winter 1996