Safe Home Rigging
Welcome to a series of articles on aerial rigging, supported by videos from Circus Rigging & Safety, sponsored by Firetoys.
When it comes to rigging at home safety is the highest priority. In this article we'll be talking specifically about static setups, for things like aerial hoops, silk, and trapeze. By static we're referring to setups that do not involve swinging, which increases the forces on the rigging considerably.
The article will go over all the points raised by the embedded video for easy reference.
Essentials aspects of rigging at home:
- Knowledge of the forces to be exerted on the rigging and surrounding structure;
- Load bearing capacity of the structure being rigged to.
Skipping these aspects is dangerous and could result in falls and injury to the user or anyone in the room with them.
Often, the best place to start is with an external consultation - get a professional in to check everything over. In the long-run it's cheaper than the repair and liability costs being risked.
We're not looking at more complex rigging solutions in this video, like pulleys. We're sticking to fixed rigging points that are most common and appropriate at home.
Misconceptions within aerial arts often revolve around how strong equipment looks to be but also how strong the forces are during training and performance. Aerial equipment is built to be incredibly strong, but the forces during even seemingly gentle movements can be far higher than you might expect.
Working Load Limit (WLL) Also known as Safe Working Load (SWL) - The maximum amount of force (not weight) that can be applied to that part of the rigging equipment.
Every piece of equipment you purchase should have a WLL. These limits will vary between pieces of equipment in a setup, it's important to know them all. That means the hoop, silk, or trapeze, but also any hooks, carabiners, strops, and wall mountings - everything.
The amount of force being applied to that equipment will then depend on the user's weight and the moves they are performing on it. The moves will multiply the user's weight producing the force applied to the equipment.
Example: The Firetoys 2-point aerial hoop has a WLL of 190kg as externally tested by a professional team.
Factor of Safety (FOS) Also known as the Design Factor or Safety Factor - A ratio used to modify the WLL down to a weight limit according to the types of material the apparatus is made from. For example, we use the lifting industry standards of 5:1 for steel, 7:1 for artificial fibres, or 10:1 for natural fibres.
This then transforms the WLL into something easily digestible - but it's still important to know the working behind it.
Dynamic Forces - The actual force placed upon apparatus during use, typically a multiple of all the weight on the equipment. Also known as Dynamic Loading or G-Force.
It's important to understand the forces you actually place on the apparatus yourself, and to keep up with changes in your style and confidence by repeatedly checking the forces. You can do this with a load cell that is placed at the top of a rigging setup and measures forces being imparted onto it.
The Firetoys 2-point Aerial Hoops are rated 190kg WLL with a 5:1 Factor of Safety.
Firetoys use permanent deformation (not destruction) for the WLL. That means that at 950kg, the 2-point Aerial Hoop was a little bit bent, and not able to return to its original shape. A WLL should not be based on destruction, but instead on an earlier "failure" in testing.
Often it's impossible to tell with the naked eye whether your chosen room can support aerial training.
If you're lucky, you may have a beam that a trained structural engineer can easily look at and make a safety declaration about. In that case, you may be able to use something as simple as a strop/spanset to get going.
Otherwise, if your setup isn't strong enough, you can reinforce your ceiling with the engineer's guidance.
Reinforcements can vary in cost, but if you're serious about training at home, it's important to invest properly and follow all professional advice. We recommend the folks over at High Performance Productions for their rigging services and safety inspections.
For any work you have done you'll also need a Completion Certificate from a surveyor for insurance purposes and to sell in the future.
Physical marking to look out for on products:
- A WLL
- An MBS
- A CE or UKCA mark
All high-quality parts should have a CE or UKCA standards mark.
On to specific pieces of rigging equipment with the eye bolt. This is a metal bolt that is sunk into concrete either in a ceiling or floor. Then it's either mechanically or chemically bonded to that surface. Very strong, and very secure, but definitely one for professionals to install.
An I-beam or Rolled Steel Joint can also be installed, and from that, an I-beam clamp designed for one will make for another type of secure rigging point.
If you have an exposed roof beam, and that beam has been inspected and deemed strong enough, then you can go the simpler route of a round sling. Whilst this is the least expensive method, it's still necessary to follow all other steps in having the beam properly surveyed.
If none of the above options are realistic for you, then you may wish to think about buying a pre-built frame, or aerial rig. These will come fully rated with a WLL from the manufacturer and are easy to set up. They do have limitations to movement that come with the angle of the legs of the rig though.
Tree rigging may be an option, but it's very difficult to recommend, and Firetoys don't recommend it. If you ever wish to rig to a tree then seek out a professional arborist, as well as a rigger. Rigging from trees can damage trees, you can't properly assess the health of the tree, and it's far harder to tell if a tree is going to handle all the forces at work.