Rigging loads are always part of a system. There may be many components or just a few but they all must work together.
For most entertainment rigging this will involve a building or at the least some sort of structure. Whatever new loads we put on the building have to have a complete path, through all of the parts, to the ground. This is where the loads will be absorbed.
This means ALL of the components of the system must work together to get the load to the ground. You cannot just make the first part of the system super strong and then not look at what it attaches to or what the next component attaches to.
I see this a lot when people are installing things. They talk about safety factors and load capacities for say the eye bolt and shackle on the gear. Ignoring the mounting of the old unistrut that they are attaching the top of their suspensions to.
This also comes up with consultants specs and safety factors. We have installed equipment with 8-1 or 10-1 safety factors onto wooden roof joists that would never handle even a portion of that load.
A well deigned system is balanced in the loads and capacities that are used throughout it.
The overdesigned system has too much cost, weight and installation time in the suspensions. Although it is unlikely to fail the suspensions these systems can be dangerous as they will inspire more confidence in the rigging than is warranted by the structure. This can cause failures in the structure.
The other extreme is the poorly designed suspension equipment. If the components are not well selected and the load is higher than the suspension capacities you can have failures in the rigging suspension.
The real goal with rigging is to find a collection of parts that will allow the loads to flow securely all the way to the ground. This must be balanced with sizing them so that they will be reasonable for the loads and use.
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