The three main parts that make up the scaffold structure include the standards, the ledgers, and the transoms. These are the pipes that make up the skeleton of the scaffold, though many other scaffolding parts are necessary to make the structure sound and usable. Platforms, for example, are used to allow workers to stand or walk while on the scaffold structure; clamps are used to connect the piping together, and casters may be installed at the base of smaller scaffolding structures to allow workers to move the structure when necessary.
Standards are the vertical pipes to which other horizontal pieces will be attached. Many standards can be stacked to create a taller structure, and they are connected with scaffolding clamps. Other scaffolding parts can be connected with the clamps as well; ledgers are horizontal cross-pieces that run between standards, and transoms are smaller pipes that run perpendicular to the ledgers to create structural rigidity and stability. The platforms, or flat pieces of wood or metal on which workers can stand, will often be laid on top of the ledgers. Some special types of clamps allow for diagonal stabilizing ledgers that form an X shape between standards. The clamp used for such purposes is known as a swivel clamp, and it is one of the most versatile scaffolding parts available.
Some of the moist important scaffolding parts are ladders and stairways. These allow workers to move from one level of the scaffolding structure to another safely. Stairways are generally safer than ladders, and workers can carry materials up stairs but usually not up ladders. Stairways do tend to be more expensive, however, and they take up a significant amount of space in comparison to ladders. The ladders often run up the side of the scaffolding, and in some cases, holes may be present in the platforms to allow a worker to move from one level to another. This poses a safety risk, so stairs are usually preferred.
Accessories can be used on scaffolds to make them far more convenient. Hoists, for example, can be mounted to the side of a scaffolding structure and used to haul materials from the ground level up to any of the platforms. This hoist mounts to the scaffolding structure and is often motorized; a pulley wheel turns to feed out cable or retract it as necessary, and the cable features a hook at one end so items can be secured to the line.