Generally there are two issues that determine if scaffolds are compatible; the first issue applies to the same type of scaffold of different designs or manufactured by different manufacturers. For example, a tubular welded frame scaffold manufactured by company A has a leg diameter of 1 inch while the tubular welded frame scaffold manufactured by company B has a leg diameter of 3 inches. Obviously, the 1 inch diameter tube would not fit onto the 3 inch diameter leg. This would make it incompatible. The second issue applies to different types of scaffolds. For example, can a tube & coupler scaffold, typically using tubes that are a nominal 2 inch diameter tube, be used with a systems scaffold that has the same diameter tube? Can this same scaffold be used with a tubular welded frame scaffold that has a tube diameter of 1-5/8”? These are legitimate questions for the scaffold inspector.
The Scaffold, Shoring & Forming Institute, SSFI, and manufacturers have guidelines about the matter. So does the Scaffold Industry Association, (SIA). The guidelines typically agree with the OSHA standards which succinctly sum it up: “Scaffold components manufactured by different manufacturers shall not be modified in order to intermix them unless a competent person determines that the resulting scaffold is structurally sound.” This means that scaffold components from different manufacturers can indeed by intermixed as long as the scaffold integrity is not compromised.
Here are factors that determine if seemingly different types of scaffolds are really compatible:
For tubular welded frame scaffolds, consider this:
For systems scaffolds, consider this:
For tube & coupler scaffolds, consider this:
This isn’t meant to be a complete list since there are many manufacturers with many products. The OSHA standards exist to ensure that intermixed equipment performs as anticipated. By requiring an evaluation by a competent person, the scaffold user will have a safe scaffold to use. If you are not comfortable determining the compatibility between scaffold components, manufacturers, materials, and scaffold types, don’t guess – contact a competent person and/or a competent/qualified manufacturer.