Noé Robert Circus Rigging Standard ACaPA 2011

CIRCUS
RIGGING
STANDARD

Noé Robert
1
Noé Robert Circus Rigging Standard ACaPA 2011

Introduction! 4
Basic Installation! 5
Carabiners! 5

Quick links! 6

Shackles! 6

Ropes! 7
Static Rope! 7

Dynamic Rope! 7

More details about the Care and Cleaning of Ropes! 7

Rope Conditions! 8

Technical Properties of Synthetic Fibres! 9

Knots! 10

Straps ! 14
Installation! 14

More details about the Care and Cleaning of Straps! 14

Wire Rope! 15
Wire rope end terminations! 15

Handling wire rope! 16

Storage! 16

Unreeling! 16

Working at height ! 17
Ascending! 17

Fall Factor! 18

Manufacture of circus equipment ! 19

Breaking Strength! 19

Working load limit (WLL), Safe working load (SWL)! 19

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Noé Robert Circus Rigging Standard ACaPA 2011

Safety Factor! 19

Dynamic Factor! 20

Calculation of the resistance of circus apparatus! 20

Conversion Chart ! 21
More...! 22
Sources! 22

Rigging Shops! 22

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Noé Robert Circus Rigging Standard ACaPA 2011

1. Introduction

« Rigging (from Anglo-Saxon wrigan or wringing, "to clothe") is the

design and construction of systems that direct and manipulate

to load bearing anchor points.

»
force in a specific environment using lines of tension in relation
Wikipedia

There are many activities and industries that make use of the advantages of a rigging system. Examples
include theatre, climbing, rescue operations, construction, sailing...

Circus rigging is unique among the industries that use rigging because circus is primarily an artistic activity.
As an artistic activity circus strives to present original and innovative performances, and the rigging for those
performances must be custom designed for each activity, in a way that is effective, portable, and aesthetic.
Every day hundreds of artists and students use acrobatic equipment in their line of work, whether it be at
school or in their jobs.

While great strides have been made in the last decade in the understanding of rigging in general, we
continue to witness many potentially dangerous situations in which the lives of users of acrobatic equipment
may be at great risk. In this manual, you will find the basics of the «Standard Rigging» to help you improve
on proper rigging of your acrobatic equipment.

5 Golden Rules for Rigging Acrobatic Equipment

Safety above all else!
Plan your installations properly.
Always choose rigging equipment that is appropriate for human loads.
Training is an essential factor in safety.
Ensure your safety by regular inspection of the equipment.

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Noé Robert Circus Rigging Standard ACaPA 2011

2. Basic Installation
Carabiners Ball lock

Carabiners are the key element in the belay chain that is part of
all aerial activities. This is why it is essential to understand their
different uses and limitations.

There are currently different kinds of locking carabiners

Auto Lock
available. Some require you to twist a knob in order to get the
carabiner off from whatever it is attached to, while others may
only require that you push a safety button. Always make sure
that the locking carabiner that you purchase has been certified.

Use a super light carabiner (Aluminium) only when weight is

absolutely critical. For all other situations steel carabiners are Twist Lock
preferable.

3 simple steps for inspecting Carabiners before each use:

OK! 1. All surfaces of the carabiner should be free of cracks, sharp
edges, corrosion, or excessive wear.
2. Gate opening and closing should be quick and easy. Be sure
the gate and any locking mechanism closes freely and
completely.
3. Rivets should not be bent, loose or missing.
This picture shows the correct
way to install carabiners for all
aerial props.

It’s highly recommended to install

screw carabiners with the screw
upside down, to prevent any
unscrewing due to vibrations.

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Noé Robert Circus Rigging Standard ACaPA 2011

Quick links

OK!

This picture shows the correct When using quick links, make
way to install quick links for all sure that the gate of the quick link
aerial props. Like carabiners, is completely closed. Encore à
when possible, it’s recommended regarder
to install quick links with the screw
upside down, to prevent any
unscrewing due to vibrations.

Shackles
Shackles are a commonly used link in Circus and Theatre rigging. Shackles are very useful in connecting
two parts of a rigging system (For example, attaching the crane bar to the suspension points). Because they
are manufactured for lifting and sailing activities, they are very strong and more resistant to shock than
carabiners.

Be aware that industrial Shackles are usually marked in Working Load (WL)
and Sailing Shackles «Normally» in Breaking Load (BL)

Fig.1 Fig.2

Screw Pin Type Safety Type Anchor

Anchor Shackle Screw Shackle

When possible, it’s highly recommended to use Safety Type Anchor Screw Shackle (Fig.2) because the
shackle presented in Fig.1 has a mechanism that could work itself out (unscrew). If you have to use Fig.1
Shackle, you must secure the pin in place after installing the Shackle to your rigging system. To do this,
apply some "thread-lock" to the screw pin and tighten carefully with a pair of pliers. In addition, use a piece of
wire and insert it through the hole in the screw pin and wrap it around the swivel mechanism a few times
before twisting the ends of the wire together to hold it in place. You should check the security of this pin prior
to each use of your rigging equipment. Instead of wire rope, you can also use Ty-rap to secure the screw pin
(refer to the same instruction as above for installation).

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Noé Robert Circus Rigging Standard ACaPA 2011

Ropes

Static Rope
A static rope is a rope which does not stretch like a dynamic climbing rope. A static rope (usually 11 mm in
diameter) is usually used as a fixed rope (attached to anchors and left in place) for climbing the rope itself
with ascenders or rappelling. Static ropes are stronger and last longer than dynamic ropes, but they are not
to be used for actual climbing, except as a top-rope because their lack of stretch and elasticity causes the
force of a fall to be placed on other parts of the climber’s safety system, including anchors and harness, and
this can lead to failure of the rigging system and severe injury.

Dynamic Rope
A dynamic rope is a specially constructed, stretchable rope. This 'stretch' is what makes it 'dynamic', in
contrast to a static rope that doesn't have any give when under load. By stretching under load, a dynamic
rope will soften the impact of extreme stresses on it, such as falls, and lessens the likelihood of failure.
Kernmantle ropes (with a jacketed core) are the most common type of dynamic rope, and nylon has replaced
all natural materials since 1945 for durability and strength.

More details about the Care and Cleaning of Ropes

Ropes should be kept away from heat, corrosive fluids, and dirt. They should be stored at room temperature,
preferably in a bag.

Safety: The life of a rope depends greatly on its use and damage, and, to a lesser extent, on care, cleaning,
and storage.

Cleaning: Ropes should occasionally be hand washed in cold water using a mild soap, then rinsed free of
soap, and spread out or hung up to dry to the air. Avoid direct sunlight, do not use a dryer, and do not place
the rope over a heat source.

Care: Keep your rope off the ground to protect it from dirt which contains sharp small chips and crystals.
Avoid contact with chemicals, acids, alkalis, bleach, oxidising agents (present in concrete), and embers,
sparks or other sources of ignition, e.g., smokers. Avoid treading on your rope as this may work sharp
particles into the core. Use climbing rope only for climbing - not for towing a vehicle.

Storage: Rope should be stored, preferably after drying, at room temperature, ideally in a storage bag.

Life Expectancy: Manufacturers recommend a retirement schedule which errs on the side of caution and
also, presumably, on the side of profit!  How long you decide to use your rope depends on your treatment of
the rope, regular inspection, knowledge of the rope's history, and its continued assessment.

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Noé Robert Circus Rigging Standard ACaPA 2011

Rope Conditions

NEW ROPE AND ROPE HISTORY

A sample of unused rope is required at all times for comparison to other
ropes in use, along with the rope’s inspection record and history.

EXCESSIVE ABRASION
If 25% or more of the fibers are damaged, withdraw the rope from service
and determine the cause.

CUT STRANDS
Rope shows two adjacent cut strands. This rope should be retired or the cut
section should be removed and the remaining rope re-spliced.

MELTING OR GLAZING
Rope showing melting or glazing caused by excessive heat. This area will
be extremely stiff. Unlike fiber compression, the melted area cannot be
mitigated by flexing the rope. The melted area should be cut out and re-
spliced or the rope should be retired from service.

DISCOLORATION
A change in the color of the fibers may be caused by exposure to chemicals.
Determine the source, and, if the rope has been in contact with damaging
chemicals, destroy the rope.

COMPRESSIONS
Rope exhibits fiber-set due to compression. Visible in the area where the
rope is loaded, it often has a slight sheen on the contact area. Do not
confuse with melting or glazing. This condition is often corrected by flexing
the rope.

Even after the first use, a new rope can be damaged irreversibly,
in this case it needs to be replaced!!!

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 Technical Properties of Synthetic Fibres
Noé Robert

High Modulus High Modulus High Modulus

Material PBO Polyester Polyamide Poly- propylene
Polyethylene Polyester Polyamide

Dyneema® Technora®,Twar Dacron®,

Trade Names Vectran® Zylon® Nylon®, Perlon® PP Multifilament
Spectra® on®, Kevlar® Trevira®

Elongation at Break 3.80 % 3.30 % 3.40 % 2.8 % 10-17% 18-24% 17-17%

Carbonisation at
Melting Point in oC 140-150°C 280-330°C 500°C does not 650°C 225-240 215-260°C 165-175°C
burn or melt

Resistance to short-term heat

70°C 200°C 350°C 500°C 170°C 130°C 80°C
in °C
Technical Properties of Synthetic Fibres

UV-Resistance Excellent Limited Limited Limited Excellent Good Sufficient

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Predominantly Good at room Good at low
Resistance to Alkalis Excellent Excellent Excellent Excellent
good temp. concentration

Predominantly Predominantly Predominantly

Circus Rigging Standard

Resistance to Acids Excellent Excellent Good Excellent

good good good

Resistance to Petroleum
Excellent Excellent Excellent Excellent Excellent Good Excellent
Based products

Will bleach.
Degrades in
Excellent
Resistance to bleaches – mineral acids &
Excellent Excellent solvent unknown Excellent Excellent
solvents oxidizing agents.
resistance
Insoluble in
organic solvents

Creeps at high Hardly Hardly Slight creep

Creep Immeasurable Immeasurable At high loads
loads measurable measurable und. Load

Residual Knot Strength ~ 50% ~ 50% ~ 30% ~ 50% ~ 50% ~ 50% ~ 50%
ACaPA 2011
Noé Robert Circus Rigging Standard ACaPA 2011

Knots
Knots allow us to expand the use of our ropes. With them we can make loops to tie into, join two ropes
together, holding and safety structures and much more. To realise these benefits you need to know which
knot to use when and how to tie it properly. You need to become familiar enough with the knots to tie them
with gloves on, in the dark, during a show. That means lots of practice and periodic revision to ensure you
haven’t forgotten.

The bends a knot makes in a rope reduce its strength. Some knots reduce strength more than
others. I try to choose the strongest knots that will do the job we need.

Bowline

One of the most useful knots to know.

The Bowline is most commonly used for forming a fixed loop, large or small at the end of a line. Even after
severe tension is applied it is easy to untie. However, because it does untie so easily it should not be trusted in
a life or death situation such as a lunge system.

Form an eye in the rope with the standing part of the rope
running underneath. Run the free end up through the eye
making a loop below the end.

Take a turn around the standing part and feed the free end
back down into the eye end there. Pull standing part to tighten
down the knot.

Strength : It is said to retain 60% of the strength of the line in which it is tied.

Figure Eight

Figure Eight is the most widely used tie-in knot by mountain climbers.
It is generally considered to be 10-15% stronger than the basic Bowline. It is easy to tie and is generally
considered to be strong and secure, which makes it a good choice when holding human charge. However, it is
difficult to untie after applying heavy load.

Fold the rope back on itself to make a bight.

Form a loop, with the working end on top of the standing part.
Bring the working end underneath the standing part.
Pass the working end through the loop.
Pull the working end to tighten.

Strength : It is said to retain 70-75% of the strength of the line in which it is tied.

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Noé Robert Circus Rigging Standard ACaPA 2011

Figure Nine

The figure nine is a variation on the classic figure eight. With all major benefits of a figure eight, it has the added
advantage of being easier to untie. It has both greater strength and bulk than a figure-of-eight loop, so is
normally used only in thin rope

It is tied as a figure-of-eight loop but with an extra turn before

finishing the knot

Strength : It is said to retain 75% of the strength of the line in which it is tied.

Double Fisherman’s

The Double Fisherman’s securely ties two ropes together and can also be used to tie the ends of a rope
together to form loops

Strength : It is said to retain 75% of the strength of the line in which it is tied.

Directional figure eight

The directional figure eight knot forms a single, fixed loop in the middle of the rope that lays back along the
standing part of the rope.

Face the far side anchor so that when the knot is tied, it lays
inward.
Lay the rope from the far side anchor over the left palm. Make
one wrap around the palm.
With the wrap thus formed, tie a figure eight knot around the
standing part that leads to the far side anchor.
When dressing the knot down, the tail and the bight must be
together.

Strength : It is said to retain 70-75% of the strength of the line in which it is tied.

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Noé Robert Circus Rigging Standard ACaPA 2011

Butterfly

The Butterfly knot provides a secure loop in the middle of a piece of rope. Load can be safely applied: from
the loop to either end of the rope; between the two ends with the loop hanging free; or, to the loop with the
load spread between the two ends.

Strength : The breaking strength of the butterfly knot is 53% with both ropes loaded, and 67% with the loop loaded.

Hunter

The Hunter's bend (or Rigger's bend) is a knot used to join two lines. It is very useful to join two bungee
ropes.

Strength : It is said to retain 75% of the strength of the line in which it is tied.

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Noé Robert Circus Rigging Standard ACaPA 2011

Clove Hitch

The clove hitch is a type of knot. Along with the bowline and the sheet bend, it is often considered one of the
most essential knots.

To tie a clove hitch, first place a loop around the pole, with the
working end of the rope on top. Run the working end round the
pole once more until you meet the place where the ropes
cross, then pass the working end under the cross. Pull to
tighten.

Strength : Depending on the situation.

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Noé Robert Circus Rigging Standard ACaPA 2011

Straps
Installation

This picture shows the amount of strength of the straps, depending on how they are wrapped around the
pipe.

75% 200% 35% 75% 200%

Example:
We have a strap with a breaking strength of 2200 KN.
We attach it to a pipe as shown in the following picture:
What is the «New» Breaking strength?

Answer:

When the straps is attached around a pipe like this, the straps break at 35% of the «Normal Breaking
Load».

If the «Normal Breaking Load» is 2200 KN, attached like this, the straps will break at 2200/100*35 =
770 KN
35 %

More details about the Care and Cleaning of Straps

... Refer to Rope care ...

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Noé Robert Circus Rigging Standard ACaPA 2011

Wire Rope
Wire rope end terminations

There is only one correct way to attach U-bolt clips to wire rope ends. The base of the clip bears on the live
end of the rope; the “U” of the bolt bears on the dead end with a thimble installed in the eye (see Fig.1).

Fig. 1 Fig. 2

YES ! NO !

Clip Spacing:

D= 6 times rope diameter

Diameter of Rope (mm) No. Clips for each Rope End

3 - 12,9 mm 3

13 - 16,9 mm 4

17 - 25,9 mm 5

26 - 35,9 mm 6

In accordance with good rigging and maintenance practices the wire rope end termination should be
inspected periodically.

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Noé Robert Circus Rigging Standard ACaPA 2011

Handling wire rope

Storage
Wire rope should be stored indoors, off the ground and covered to protect it from moisture, dirt, dust,
sunlight, etc.

Unreeling
Wire rope must be unreeled or uncoiled as shown. When unreeling, a helper can use a board as a brake to
control the spin. Do not pull wire rope sideways off the reel.

YES !

NO !

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Noé Robert Circus Rigging Standard ACaPA 2011

3. Working at height
Ascending
Backed-up ascend using a Y-shaped energy absorbing lanyard.
This kind of safety system is really useful when climbing on king pole or lighting structures

Ascending a short distance Ascending a long distance

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Noé Robert Circus Rigging Standard ACaPA 2011

Fall Factor
The Fall Factor is a rating used to evaluate the danger of specific
scenarios when working at height. The Fall Factor is calculated
using the following equation:
Fall Factor = Height of Fall / Length of Lanyard
In situations where the Fall Factor will be 0 (e.g. the worker is
positioned under the anchor point on a tensioned lanyard) or in
situations where the Fall Factor is 1 or less and the freedom of
movement is limited to 0.6 m or less, positioning equipment is
adequate.

Fall arrest equipment must be used for other situations, where

the Fall Factor is greater than 1 or more freedom of movement is
required.
Systems involving Fall Factors include:

Restraint: a technique used to prevent a worker from entering a

fall risk area (e.g. positioning harness and lanyard EN 358).

Positioning: a technique used to position a worker securely in a

fall risk area without creating a Fall Factor scenario (e.g. hanging
beneath an anchor point in a positioning harness on a tensioned
lanyard EN 358).

Fall Arrest: a technique used to catch and reduce the force of a

fall from heights (e.g. use of a Fall Arrest Lanyard EN 361 and
Shock Absorbing Lanyard EN 355)

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Noé Robert Circus Rigging Standard ACaPA 2011

4. Manufacture of circus equipment

Breaking Strength

Breaking strength (BLL) is the most essential information needed concerning materials used for circus
rigging. Minimum breaking strength (Mbs) is the lowest result gathered in a series of tests to find the ultimate
breaking strength of a material. The circus rigging standard recommends the use of minimum breaking
strength values when they are available. The minimum breaking strength of the weakest part of the
rigging system is the minimum breaking strength of the system.

Working load limit (WLL), Safe working load (SWL)

The term safe working load (SWL) has for many years been the cornerstone of engineering to load carrying
equipment. The SWL was generally considered to be the breaking load of a component divided by an
appropriate factor of safety, thus providing a ‘safe’ load to be lifted. About 20 years ago, however, the USA
ceased using this term because of legal implications.

Over the past two or three years, both the Americans and Europeans have agreed that the term working load
limit (WLL) should replace the term safe working load (SWL). A general definition of WLL is: The maximum
mass or force which a product is authorized to support.

Safety Factor

The safety factor is calculated as a ratio between the static weight that will load the equipment and the
breaking strength of the equipment. This ratio must cover unidentified risk factors such as incalculable forces
induced by movement, changing climatic conditions, age of the material, variations during the production of
the material, and more.

All apparatuses, used for aerial rigging must take into account the following design factor:

SAFETY FACTOR

SAFETY
Material
FACTOR

Steel 4

Aluminium 4

Steel Cable 5

Textiles 7

Mixed Material 7

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Noé Robert Circus Rigging Standard ACaPA 2011

Dynamic Factor

The dynamic factor takes into account the effect of movements of the artist during work: including
amplification of the load through swinging, spinning, lifting, use of mechanical advantages, and changes
caused by hanging the load from lines at various angles, as well as shock loading.

DYNAMIC FACTOR

DYNAMIC
CIRCUS APPARATUS
FACTOR

Fixed apparatus
2
(Vertical rope, silk, aerial hoop, static trapeze)

Swinging apparatus
5
(Swinging trapeze, Cloud swing, Flying trapeze, …)

Climbing gear is marked with a load rating that indicates it's Breaking Load Limit (BLL)
Construction rigging is often marked in Safe Working Load (SWL)
Yachting rigging is marked in Safe Working Load (SWL) or Breaking Load Limit (BLL)

Calculation of the resistance of circus apparatus

( WEIGHT OF
THE
APPARATUS
+ WEIGHT OF
THE USER
) x DYNAMIC
FACTOR
= ACTIONS

Analysis of forces
depending on the position
of the masses and
geometry of the rigging

BREAKING LOAD

≤
COEFFICIENT OF USE
STRESS IN THE ELEMENT

or

≤ WORKING LOAD LIMIT

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Noé Robert Circus Rigging Standard ACaPA 2011

5. Conversion Chart
RIGGING GLOSSARY

ENGLISH FRENCH DEFINITION

BLL CR Breaking Load Limit

SWL CMU Safe Working Load

WLL CMU Working Load Limit

RWL Recommended Working Load

Mbs CmR Minimum breaking strength

Millimetres Inches Millimetres Inches

1 1/32" 13 1/2

2 1/16" 14.5 9/16

3 1/8" 16 5/8

5 3/16 19 3/4

6.5 1/4 22 7/8

8 5/16 26 1

9.5 3/8 29 1 1/8

11.5 7/16 32 1 1/4

kN lb kg kN lb kg

1 225 102 9 2023 918

2 450 204 10 2248 1020

3 674 306 15 3372 1530

4 899 408 20 4496 2039

5 1124 510 25 5620 2549

6 1349 612 30 6744 3059

7 1574 714 35 7868 2569

8 1798 816 40 8992 4079

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Noé Robert Circus Rigging Standard ACaPA 2011

6. More...
Sources
www.petzl.com
www.horslesmurs.fr/plugins/.../Memento%20agres.pdf
http://www.machinerie-spectacle.org/accroche-levage
www.barry.ca
www.toprockadventures.com
www.mesnoeuds.free.fr
www.animatedknots.com
Circus Rigging Stardart, Second edition October 2006 by Cris Clark
The Complete Book of Knots (Jul 1, 1997) by Geoffrey Budworth
The Ultimate Encyclopedia of Knots and Ropework: Over 200 Tying Techniques with Step-by-Step
Photographs (Jan 16, 2010) by Geoffrey Budworth

Rigging Shops

www.barry.ca
www.hauteurshop.com
www.hisseo.net
www.mbta.fr
www.showbiz-france.com
www.freeworker.de
www.usrigging.com
www.stageriggingonline.com

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