Scaffold tubes must be regularly checked to ensure that that they are straight, clean at both ends, free from cracks, dents, splits and excessive corrosion.

A scaffold ability to carry its required load will depend on the condition and strength of the tubes used for its construction.

Lightly corroded aluminium tubes should be cleaned with a wire brush. Bent aluminium tube should be discarded, however bent steel tubes can be straightened using a rolling machine.

Aluminium scaffold tubes have an outside diameter of 48.3mm, a nominal wall thickness of 4.5mm and a weight of 1.7kg/m.

Aluminium scaffold tube shares the same outside diameter as steel tubes but are slightly thicker and much lighter. Aluminium tubes are more flexible than steel tubes are more flexible then steel tubes but not as strong, for this reason aluminium tubes should not be used with steel tubes on the same lift. However the lighter aluminium tubes can be placed on top of the steel tubes for tall scaffold structures.

Type-4 steel scaffold tubes have an outside diameter of of 48.3mm, a nominal wall thickness of 4.0mm and a weight of 4.4kg/m. Type-3 steel scaffold tubes are slightly thinner with a wall thickness 3.2mm.

Black steel and galvanised steel scaffold tubes share the same dimensions, however galvanised tubes are more resistant to corrosion.

There are three main types of scaffold tubes commonly used , black steel tubes, galvanised steel tubes and aluminium alloy tubes. Scaffold tubes are manufactured to BS EN39:2001 (Loose Steel Tube for Tube and Fitting Scaffolds).

Sleeve couplers often just called sleeves can be used to connect scaffold tubes end to end. Unlike joint pins this fitting has a resistance to bending and has a safe working tension of 315kg.

A base plate which is usually made form steel, will have a central shank for locating the scaffold tube. In some cases the base plate may be fixed to a sole board to help prevent lateral movement, especially if a foot tie or kicker lift isn't used.

Standards, also known as uprights, are the vertical tubes which holds the full load of the scaffold to the ground. Every standard must have a base plate which stops the end of the scaffold sinking into the ground.

To connect scaffold tubes end to end a joint pin (or expanding spigot can be used). The joint pin or spigot is inserted into the end of the scaffold tubes and a centre bolt is tightened. This tightening causes the two parts of the joint pin to expand gripping the ends of the scaffold tubes. It is essential not to use this fitting in situations where it will be subject to tension or bending.

Ledgers are the horizontal tubes which connect with and support the standards. Ledgers also act as supports for transoms and will usually run in the direction of the larger dimension of the scaffold. Depending on the intended use of the scaffold will determine the vertical spaces or distances between the ledgers.