Rigging
Proficiency
Level 1
Introduction
Simply stated the job of the riggers is to hang all of
the show equipment that must be supported by the
structure of the building. Examples include:
Lighting Trusses
Speaker Systems
Video Walls
Set Pieces
Projection Screens
Backdrops
Cable Picks
2
Types of Rigging
• Industrial- Marine, military, crane and factory rigging
fall into this category. General Industry is were
many of the components of the following areas
borrow techniques and components from.
• Arena- Large arenas and stadiums fill up this
category. Very similar to theatrical applications
with industrial components.
• Theatrical- A strong hybrid of Industrial and Arena
rigging. Many unique components and historical
techniques.
• Aerial- Techniques refined for the flight of people
with an emphasis on the performance aspect of
rigging. Usually lighter components.
3
Rigger-Industrial/Arena
Requires ability and working knowledge of:
Methods of suspending large truss assemblies
Work Load Limit and proper application of components
Various codes, standards, regulations, and industry
practice related to overhead lifting
Work Load Limits of various types of box trusses
Installation, operation, and repair of chain hoists
Calculation of bridle lengths
Calculation of loads in bridle legs and is familiar with
OSHA standard 1910.184 and ANSI standard B30.9 for
slings and bridles
Able to work at height
Understands and practices safe methods of fall protection
4
Rigger-Theatrical
Theatrical riggers must have a working knowledge of
theatrical rigging systems, the hardware and its proper
installation.
We must understand the Work Load Limit and proper
application of a variety of hardware and fittings, including:
wire rope
wire rope clips
chain
chain fillings
hooks
bolts
and shackles.
Know and understand the various codes, standards,
regulations, and industry practice related to overhead lifting
and their application in theatrical rigging systems.
5
Introduction
Rigging Components
Work Flow
Fall Protection
Lifelines
Procedures
Rescue
Rigging from Lifts
6
Rigging
Components
Wire Rope
Wire rope, a.k.a. steel or cable, is one of the most
common and important tools that riggers use. Wire
rope is constructed from individual steel wires
twisted together to form strands. Strands are
wound around a core to form a rope. There are
many different types of wire rope designed for
varying applications.
The most common type of wire rope used for
arena rigging is 6x19 IWRC (internal wire rope
core), made from extra improved plow steel. This
rope has six strands wound around a wire rope
core. Each stand is made up of 19 individual wires.
8
Wire Rope
Wire rope lengths used for arena rigging have
mechanical eye splices made around steel thimbles.
This type of splice retains 95% of the original
strength of the wire rope. The swage is the sleeve
which is pressed by machine to form the eye splice.
swage
eye
thimble
wire rope
9
Wire Rope
Two sizes of wire rope are commonly used for arena rigging. 3/8” wire
rope is typically used with one-ton hoists and 5/8” shackles. 1/2” wire
rope is typically used with two-ton hoists and 3/8” shackles. The table
below gives nominal break strengths for 6x19 IWRC, extra improved
plow steel, wire rope.
The 5% strength reduction factor for the mechanical eye splice has
been figured into the table.
•
size
strength
3/8”
.26
1/2”
.46
weight lbs./ft.
nominal
14,345 lbs.
25,270 lbs.
Lengths of wire rope are often color-coded with spray paint for easy identification as follows:
length
5ft.
10ft.
20ft.
30ft.
50ft.
color
red
white
blue
green
yellow
10
Rules for Wire Rope
Never put more than one fitting through an eye splice.
Never bend wire rope within four inches of the swage.
Never use a length of wire rope with a broken wire.
Never use rusty wire rope.
Never use wire rope with bent or malformed thimbles.
Always pad corners and edges that wire rope will
bend over.
Whenever possible choose lengths of steel that are
less kinked and twisted.
11
Spansets
Spansets, a.k.a. round slings, consist of circular
strands of polyester covered by a nylon sheath.
Lengths ranging from one foot to ten feet are
commonly used for arena rigging. The length of a
spanset is not determined by its diameter, but by
pulling the loop taught and measuring the inside
length.
Length
By law, all spansets must have a tag listing working
load limits and length. Don’t use a spanset without a
12
tag.
Spansets
Spansets are very strong and very
flexible. They are used in
applications where wire rope would
be too abrasive or too inflexible, e.g.
for slinging trusses. Round slings
are susceptible to damage by fire or
chemicals. They generally are not
as durable as wire rope slings and
are more expensive. It is important
to inspect each sling prior to use.
visibly damaged slings should never
be used.
13
Shackles
Shackles are the steel links used to attach rigging
components. Shackles consist of two parts; the pin
and the bell, a.k.a. bow. Shackles used for arena
rigging have a threaded pin which screws into the
bell.
bell
threads
flange
pin
14
Shackles
Three sizes of shackles are commonly encountered in arena
rigging; 1/2”, 5/8”, and 3/4”. The table below provides
information on these three sizes and the size of wire rope to
be paired with it.
•
size
rope
1/2”
5/8”
3/4”
working load limit
4000 lbs.
6500 lbs.
9500 lbs.
.72 lbs.
1.37 lbs.
2.35 lbs.
weight
wire
1/4”
3/8”
1/2”
A commonly encountered problem with shackles
used for arena rigging is botched pin threads. Don’t
use shackles with pins that are hard to turn. The
exception to this is a pin that is hard to turn due to
fresh paint. To correct this problem, work the pin in
and out several times to loosen the paint.
15
Shackles
Shackles are designed to be loaded in two or three directions.
If they are to be loaded in three directions, one direction must
be on the pin and the other two on the bell. Shackles are not
designed to be cross loaded, i.e. in two directions on the bell,
but not on the pin. Cross loading reduces the working load limit
by half.
load
load
load
INCORRECT
load
load
load
load
cross loading
16
Turnbuckles
• Construction: Galvanized, Stainless Steel
• Domestic vs. Import
• Different end connections: eye, clevis, hook and
round eye
• Orientation right and left handed threads
• WLL usually not printed on the component
• Not for use in a dynamic situation.
• Exercise:
o How to tighten and loosen properly
o How to mouse and tie off properly
17
Deck Chain
Deck chain, aka STAC
(Special Alloy Chain) is
designed for making
small adjustments in the
length of rigging
components.
18
Deck Chain
The standard length of a deck chain is
three feet.
Each link is four inches long.
The W.L.L. is 12,000 lbs. With a 4:1
design factor.
A link will accept up to a ¾” shackle.
19
Hardware
Components
and Use
Hitches
Choke
21
Hitches
Basket
22
Hitches
Split Basket
23
Deadhang
• Deadhangs are used to suspend loads directly below
beams.
Beam Pad
Basket
Free Shackle
Working
Shackle
Down Leg
(Stinger)
Hoist Hook
24
Bridle
Baskets
Bridle
Legs
Apex
Hoist Hook or
Stinger
• Bridles are
used to
suspend loads
between
beams.
• Adjusting the
length of the
bridle legs
allows a rigger
to hit any
point
between the
beams.
25
Deck Chain
Working
links
Dead
links
Hoist
hook
Hoist
chain
Target point
A
B
Deck chains are
used to adjust the
length of bridles
Doing so allows
riggers to shift
points without
having to move
the bridle
26
Truss
Truss is used in arena rigging to suspend equipment
such as lighting instruments, speakers, curtains and
set pieces. The trusses are usually slung with round
slings, clipped to chain motor hoists, and raised to
the desired trim height. Truss is usually made from
welded steel or aluminum tubing. To save weight,
aluminum truss is more commonly used.
There are three main truss configurations:
Horizontal Box Truss
Tower Box Truss
Triangular Truss
27
Truss
Horizontal box truss: Consists of four main pipes supported by
perpendicular cross-members on the top and bottom, and
diagonal cross-members on the sides.
side view
top view
Diagonal cross-members make stronger truss than perpendicular crossmembers. Since horizontal box truss is designed with diagonal crossbracing only on the sides, it is only meant to be loaded on one axis, with
the load suspended directly below it. Side loading horizontal box truss,
or assembling it with the perpendicular cross-members on the
28
sides, results in a weaker truss configuration.
Truss
Tower box truss: Consists of four main pipes supported by
diagonal cross-members on the top, bottom and sides.
side view
top view
The diagonal members on all four sides of tower box truss make it
strong vertically and horizontally. It should be used in applications
where a vertical and horizontal load may be applied simultaneously.
It is also designed to be stood on end and used as a vertical pillar or
tower.
29
Truss
Triangular truss: Consists of three main pipes
supported by diagonal cross-members on all three sides.
side view
top view
Triangular truss is usually suspended in a point down
configuration as shown in the end view above. Loads suspended
from the bottom chord (point), are less apt to spin the truss.
Triangular truss may also be used as a vertical pillar or tower.
30
Truss
Trussing typically comes in sections which are bolted together to
make a truss of the desired length. Care must also be given to
match the pattern of the cross-members which make up the sides
of the truss.
CORRECT
INCORRECT
INCORRECT
31
Truss Bolting
Use a spud wrench to line up bolt holes as needed.
Keep the bolts loose until all four are made.
Be sure to use one washer on the bolt side and one washer on
the nut side.
Always torque truss bolts with a socket wrench. Two 8”
Crescent wrenches won’t provide adequate torque.
Flying truss with loose or missing bolts could be potentially
disastrous.
Always double check that all the bolts are tight before flying
truss.
32
Rigging Hardware
•
•
•
•
•
•
•
•
•
Eye bolts
Block and Falls
Come-a-long
Lever Hoist
Chain Falls
Theatrical Pipe
Pipe Clamps
Ratchet Straps
Arbor Weight
33
Eye Bolts
•
•
•
•
•
•
Come in various sizes and shapes
Shouldered and non-shouldered
Examples in training structure
Import and Domestic
Meant to take load in a vertical configuration only.
Remember that the W.L.L. decreases when a Eyebolt is pulled from an angle.
34
Lever Hoist and Chain
Fall
• Chain Fall
o ¼,1, 2 and 3 ton models
o Used in place of motors sometimes
o Do not require power
o May be limited by the amount of chain
• Lever Hoist
o Used to lift loads short distances
o No power necessary
o 1, 2 and 3 ton models available.
35
Pipe clamps and Pipe
• Pipe clamps
o Also called Chez Boroughs
o Used in lighting and rigging
o Beware of the WLL of the clamp
o Steel and Aluminum models available
• Pipe Schedule 40 and Schedule 80
o Used in theatrical Rigging
o Outside Dia. of 1 ½” to 4”
o Most common is 2” OD
36
Ratchet Straps
• Ratchet Straps
o
o
o
o
o
o
o
Used for theatrical, arena and Industrial use
Come in sizes of 1” and 2”
Used tagged and newer models when available
Several different hook and end connections available
Endless loop models and hook models
Lubricate regularly
Inspect prior to use
• Conduct Exercise using 2” endless loop
ratchet.
37
Motorized Hoists
&
Load Distribution
Chain Hoists
• The most commonly
used hoists for
theatrical rigging are
CM™ Loadstar chain
motor hoists.
½-ton and 1-ton
hoists have single
reeved chains.
2-ton hoists have
double reeved chains.
39
Chain Motor Hoists
Electric chain motor hoists are
the most common tool used to
suspend loads for arena rigging.
hook
swivel
chain
control cable
power cable
eye bolt for chain bag clip
to control box
chain bag
•
•
•
Three sizes of hoists are commonly used:
Size
1/2 ton
1 ton
2 ton
Speed
16 ft./min.
16 ft./min.
8 ft./min.
Weight
62 lbs.
98 lbs.
110 lbs.
.6
.8
1.6
Chain Weight/ft
lbs.
lbs.
lbs.
40
Drum Hoists
or Winch
•Typically used for
performer flying and
scenery
• High performance
and high cost.
Typically a permanent
install item.
• Portable units used
in movie stunts and
arenas.
41
Load Distributions
• Two Point Truss
.5
.5
Evenly Distributed Truss
42
Load Distributions
• Three Point Truss
.1875
.625
.1875
Evenly Distributed Truss
43
Load Distributions
• Four Point Truss
.133
.367
.367
.133
Evenly Distributed Truss
44
Load Distributions
• Five Point Truss
.098
.286
.232
.286
.098
Evenly Distributed Truss
45
Rigging Techniques
• Tag lines
• Hard hat safety, glasses, gloves, steel toe work
boots
• Placing wood pads underneath crane
Talking to crane operator:
How to signal the lift
Destination of the load
Direction of the swing
Radios work better when the signal man cannot be
seen
• Proper footprint of the crane to be looked at before46
•
•
•
•
•
-Lifting points
1.
Not a positive connection
2.
Enables two part sling
3.
Easier to unhook
4.
Requires a vertical pull
5.
Good for hooking below top
6.
Obstructions above trunnion a
problem
47
Anchor and Lifting
Equalization
• Needs to be done when
dispersing the weight of a
load over a long or short
distance.
• Can lower the need for
single point attachments
• Several attachments
spread out can raise the
lifting device capacity
48
Center of Gravity
• Usually marked or mathematically found and
marked by an engineer
• Can be found by running a tape measure
down the object to be lifted and marking
center if a balanced load
• May be off center with certain pieces
• May need to be considered variable when
lifting liquds
• Extremely important when lifting
• Sometimes found with trial and error with lighter
objects
49
Center of Gravity
50
Work Flow
Work Flow for Load in
Mark the plot on the floor using tape measures and chalk.
Place appropriate motor next to each marked point.
Assemble wire rope, shackles, deck chain, etc.
Road riggers instruct the sequence of points that are pulled.
Riggers position themselves on the beams above points.
Lower in ropes positioned in the proper upstage / downstage
and cross-stage planes.
One rope needed for a deadhang and two ropes for a normal twoleg bridle.
Ground riggers double check that components are assembled
correctly and that the ropes are hanging in the correct planes
and free of obstruction.
A bowline is used to tie the rope into the
appropriate shackle. Length of the bowline
loop is determined by consultation with the
high rigger and/or knowledge of the required
length for a given beam.
52
Work Flow for Load in
High riggers attach the components around the appropriate
beam and have the point checked for position.
A ground rigger plumbs the chain and puts body weight on it.
This chinches the hitches and takes the sag out of bridle legs.
If a plumb chain does not fall in the middle of the point drawn on
the floor, the ground rigger asks for it to be slid along the beam
until it does. If sliding doesn’t allow the point to hit the middle of
the mark, the head or road rigger must be consulted for
adjustment of the component lengths.
Riggers move from point to point until the entire show is hung.
Two designated high riggers stay behind and double check the
correct assembly of each point before returning to the floor.
Storage cases and empty motor cases are moved into a storage
area.
A small rigging crew stays until all the chain motor hoists are at
trim height.
This is a precaution in case of a bad motor which must be swapped
out.
53
Work Flow for Load out
Ground riggers retrieve stored cases and high riggers to head
for the grid.
Motor cases are placed near where each point will land.
Storage cases are positioned in a central location.
Hoists run until the equipment is at a convenient work height.
The equipment is removed and the truss landed on the ground.
Pickle (local control) is used to lower the hoist into road case.
Hoists run to limit, motor reversed for a couple of links.
Pile the excess chain into the case.
Disconnect the strain relief clip.
Disconnect power cable and pickle.
Clip the empty chain bag onto box.
Motor box is now prepped for the
high rigger to lower in the remainder
of the chain.
54
Work Flow for Load out
High rigger ties into the proper shackle, lifts and holds the weight
of the point and disassembles the hitches around the beams.
When the high rigger has disassembled the hitches and is ready
to lower the components to the ground, he calls to the ground
rigger and waits until he are in position to receive the point.
Ground rigger verbally controls the rate of descent.
Ground rigger ensures that no one walks beneath the point as it is
being lowered and guides the chain into the road case.
Ground rigger then guides the wire rope and other components
onto the floor.
Coil the wire rope.
Fold the burlap beam pads.
Store the shackles, spansets,
and deck chain in the appropriate
cases.
55
Fall Protection
Harnesses
Only full body harnesses
are acceptable for fall
arrest.
OSHA 1926.502 (D) (17)
“The attachment point of
the body harness must
be in the center of the
wearer’s back near
shoulder level, or above
the wearer’s head.”
57
Lanyards
Only shock absorbing lanyards
are acceptable for fall arrest.
The lanyard must have a
nominal break strength of 5,400
pounds and a withstand a tensile
load of 4000 lbs. without
deformation.
The lanyard length must be
adjusted to provide a free-fall of
no greater than 6 feet and
prevent contact with lower levels.
58
Lanyards
OSHA 1926.502 (D)(5)
“Snaphooks shall be sized to be
compatible with the member to
which they are connected to
prevent unintentional
disengagement of the snaphook
by depression of the snaphook
keeper by the connecting
member.”
Only locking connectors are
acceptable for fall arrest.
59
OSHA Fall Protection Regulations Section 1926.501B(1)
“Unprotected sides and edges.” “Each
employee on a walking/working
surface (horizontal and vertical
surface) with an unprotected side or
edge which is 6 feet (1.8m) or more
above a lower level shall be protected
from falling by use of guardrail
systems, safety net systems, or
personal fall arrest systems.”
60
OSHA Training Requirements
OSHA 1926.503 (A)(1) “The employer shall provide a
training program for each employee who might be
exposed to fall hazards. The program shall enable each
employee to recognize the hazards of falling and shall
train each employee in the procedures to be followed in
order to minimize these hazards.”
OSHA 1926.503 (B)(1) “The employer shall verify
compliance with paragraph A of this section by preparing
a written certification record. The written certification
record shall contain the name of the employee trained,
the date(s) of the training, and the signature of the person
who conducted the training or the signature of the
employer.”
61
Passive Fall Protection
Passive Fall Protection Systems help prevent falls
from heights. They are preferable because they
require no action on the part of the workers they
protect.
Examples include:
Guardrails
Personnel Nets
Hole Covers
Ladder Cages
62
Fall Protection
The following rules apply to personal fall protection equipment:
Fall protection equipment must fit properly, be
adjusted correctly, and inspected before each use.
All components must have a min. break strength
of 5000 lbs.
Lanyards must limit the arresting force on a rigger
to 900 lbs.
Riggers must not free-fall more than 6 feet or
contact lower levels.
Lanyards must be attached to the harness in the
center of the riggers back.
Any equipment subject to impact loading must be
removed from service and replaced.
63
Fall Arrest vs. Fall Restraint
Fall restraint systemsinvolve the use of a
body belt which
prevents a worker from
reaching an area where
a free-fall could occur.
Body belts should never
be used if there is any
chance of a free-fall.
64
Fall Arrest vs. Fall Restraint
Fall arrest systemsprotect workers who
must access areas
where free-falls are
possible. Fall arrest
systems are designed
to stop a free-falling
worker. Full body
harnesses and shockabsorbing lanyards are
required.
65
Personal Fall Arrest Systems
Personal Fall Arrest Systems
consist of:
Anchorage Connector
Shock Absorbing
Lanyard
Full Body Harness
Personal Fall Arrest Systems
All personal fall arrest components must be inspected
for damage prior to each use.
All fall arrest components must have a minimum tensile
strength of 5000 lbs. (22.2 KN)
Maximum weight for a rigger and tools is 310 pounds.
Any personal fall arrest equipment subjected to impact
loading must be immediately removed from service.
Maximum arresting force on a person wearing a full
body harness must be 1800 lbs. or less
Maximum deceleration distance is 3-1/2 feet.
67
Calculating Fall Distances
A six foot shock
absorbing
lanyard requires
a minimum
18-1/2 foot
clearance
between the
attachment point
and the lower
level.
68
Anchorage
OSHA 1926.502 (D)(15)
“Anchorages used for the
attachment of personal fall
protection shall be
independent of any
anchorage being used to
support or suspend
platforms and capable of
supporting at least 5000 lbs.
(22.2KN) per employee
attached.”
69
Anchorage
Workers on suspended
scaffold, (swing stages), must
have a fall protection
anchorage independent of the
anchorage for the scaffold.
Riggers working on rappel
must use an OSHA compliant
fall protection system in
Rappel line
addition to the rappel rope.
Fall protection line
70
Anchorage
OSHA 1926.502
(D)(23) “Personal fall
arrest systems shall
not be attached to
guardrail systems, nor
shall they be attached
to hoists.”
Don’t attach your fall
protection, i.e.
lanyards, here.
71
Lifelines
Self Retracting Lifelines
Self retracting lifelines
are spring loaded cable
reels that automatically
adjust the length of
cable.
In the event of a fall, a
centrifugal brake
engages, (just like a
car’s seat belt).
Climbing up or down
too quickly may engage
the brake or build slack
in the cable.
73
Self Retracting Lifelines
SRL’s are designed to
be clipped directly into
the back d-ring.
Depending on the
type of SRL, attaching
a shock absorber
between the harness
and SRL may result in
a greater fall distance
and overload the SRL.
74
Vertical Fall Arrest
OSHA 1926.502 (D)(10)(I) “When vertical
lifelines are used, each employee shall be
attached to a separate lifeline.”
OSHA 1926.502 (D)(12) “Self retracting lifelines
and lanyards which automatically limit free fall
distances to 2 ft. or less shall be capable of
sustaining a min. tensile load of 3000 lbs.(13.3
KN).”
OSHA 1926.502 (D)(13) “Self retracting lifelines
and lanyards which do not limit free fall
distances to 2 ft. or less, ripstich lanyards, and
tearing and deforming lanyards shall be
capable of sustaining a min. tensile load of
5000 lbs.(22.2 KN).”
75
Vertical Lifelines
Rope grabs or
cable grabs are
typically used to
attach workers
to vertical
lifelines.
76
Vertical Lifelines
3 ft. is the maximum
lanyard length when
attaching to a trailing
rope or cable grab.
Be sure your rope
grab is traveling
along the rope
properly. This
prevents either
hanging from it or
creating slack in the
lifeline.
77
Horizontal Lifelines
OSHA 1926.502 (D)(8) “Horizontal lifelines shall be
designed, installed and used, under the
supervision of a qualified person, as part of a
complete fall arrest system, which maintains a
safety factor of at least two.”
78
Horizontal Lifelines
Horizontal lifelines typically require large
clearances above lower levels.
79
Horizontal Lifeline
80
Lifeline Anchorage
Tying knot a or choking
around a beam,
significantly reduces the
strength of a lifeline.
Lifelines are not
designed to support the
required load if they
have been knotted or
choked.
All sharp surfaces must
be avoided or padded to
prevent the cutting or
abrading lifelines.
Make connections as
shown above.
81
Procedures
Procedures
Workers are required to use a fall protection
system 100% of the time when exposed to fall
hazards.
Y-lanyards are used to allow workers to remain
attached to the fall arrest system at all times.
83
Procedures-Swing falls
Workers must
not be allowed to
take swinging
falls into walls,
beams or other
objects.
Anchorage
should be made
directly above
workers.
84
Procedures
In order to
prevent a freefall greater than
six feet:
The attachment
on the harness
must be at or
below the level
of attachment to
the anchorage,
or the lanyard
must be
shortened.
OK OK NO!
85
Rescue
Rescue
OSHA 1926.502 (D)
(20) “The employer
shall provide for
prompt rescue of
employees in the
event of a fall or
shall assure that
employees are able
to rescue
themselves.”
87
Rescue
Self Rescue: The fallen worker climbs to
safety.
Assisted Rescue: Co-workers help the fallen
worker to climb to safety.
Ladder/ Manlift Rescue: Co-workers either
lower a ladder or raise a manlift to the fallen
worker.
Roped Rescue: Employs a belay line and
lifting apparatus to secure the fallen worker &
raise them to safety, or lift them off their fall
protection and lower them to the ground.
88
Rigging from Lifts
Lifts
• Personnel lifts come in various
sizes, configurations, and power
sources.
• Three main types of personnel
lifts are used for entertainment
rigging:
Single person Genie™ lifts
Scissors lifts
Boom lifts
90
Lifts
Genie™ lifts are
one-person work
platforms small
enough to be
loaded onto trucks
by hand.
They are typically
pushed into place
then raised with an
electric motor.
Genie™ lifts have
removable
outriggers which
must be in place to
raise the platform.
91
Lifts
“When working from
an elevated scissors
lift (ANSI A92.6), a
worker need only be
protected from falling
by a properly
designed and
maintained guardrail
system.”
OSHA Standards
Interpretation and
Compliance Letters
07-21-98
92
Lifts
OSHA 1926.453(b)
(2)(v) “A body belt
shall be worn and a
lanyard attached to
the boom or basket
when working from an
aerial lift”
OSHA 1926.453(b)
(2)(iii) “Belting off to
an adjacent pole
structure or equipment
while working from an
aerial lift shall not be
permitted.”
93
Thank You for
Your Time