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 Ladders: Type and Use

A ladder is a device for reaching high places. The simplest and most common type of ladder is a wooden construction consisting of two sides that rest on the ground, called the rungs, and support at least one intermediate horizontal section called the top or batten.

The basic types of ladders are:

• Extension ladder: an A-frame structure with no end supports (with or without a platform).

• Platform ladder: a scissor-type structure with two fixed supports, no end supports (with or without a platform).

• Extension ladder ("murphy" type): A-frame structure with end supports only (without a platform).

• Extension ladder ("coffin" type): A-frame structure with end supports only (without a platform).

A "scaffold" is usually an extension ladder or a platform, or in some cases an A-frame and top. The term "scaffolds" can also refer to structures used for other purposes. For example, on building sites they may be stands for scaffolding poles to support window washing materials.

A ladder may have only two rungs, termed "single ladder" or "double ladder", or more. As a general rule, the more rungs there are, the longer and sturdier the ladder. It would be a dangerous mistake to purchase a residential type extension ladder for use in an industrial environment. The following guide can help you choose the right kind of ladder for your needs:

• For home use on low heights, a single-ladder model (non-folding) is usually sufficient.

• For construction sites and other types of industrial use, apart from using scaffolds, skilled workers will often use double ladders (folding) with three or four sections.

• In general, the maximum allowable load for a ladder is determined by its type, material and length. As a rule of thumb, the safe working load is approximately 100 kg per rung. The number of workers who can safely work on a scaffold at any given time depends on the type of scaffold, type and weight of materials used and other factors such as wind speed and direction.

"Ladder safety" is concerned with how to erect, use and dismantle ladders safely.

Situational training, in particular to learn how to use ladders in certain situations, is beneficial. You should train your ladder-using co-workers and anyone else who may need to use the same type of ladder, so they can correctly follow instructions when using the ladder.

There are three main ways of erecting a ladder; these are: 'up the side', 'on end' and 'ready formed'.

Safety instructions for various types of ladders:

A fall with a ladder under which you have been working can cause serious injury with broken bones, sprained or crushed limbs, severe bruising and so forth. A fall on the ladder will also cause damage to the bottom of the ladder.

The following are some useful rules:

When you work at heights, it is extremely important to keep yourself and your tools in good working order and safe from injury – always wear engineering-style 'safety boots' or similar footwear, when necessary.

• When using a ladder always follow the instructions for its use that came with it.

• Always ensure no flammable materials are on a working platform. 

• Always ensure that you have sufficient grip with all of your ladder feet.

• Always use a ladder in good condition, and never paint it without first checking that the paint is suitable for application to metals.

• When loading or unloading goods, never lean a ladder against these goods. Place the goods or yourself as close as possible to the ladder's base instead.

• Always check a ladder before you place any part of your weight on it.

• Never walk under a ladder that is being used to work from and always make sure it is secured at the base when not in use.

• When descending a ladder, you should hold the side rails with both hands and move down the rungs facing them, not sideways.

• Only use a ladder under the supervision of an experienced person.

A "two-point set-up" is when there are two points of contact with the ground or other firm supports, such as trees or poles. This is accomplished by placing two supports at equal distance from each other on the ground, such as a tent pole and a stake. One end of the ladder rests on each support. A variation of this setup is to add an additional support on one side only so that the ladder itself acts both as its own side rail and bring up one rung from the floor for stability when using it in this manner (the 'cheater' method).

A "three-point set-up" is when there are three points of contact with the ground or other firm supports, such as trees or poles. This is accomplished by placing two supports at equal distance from each other on the ground, and then anchoring a third support to the structure to be worked on and approximately halfway up the exposed side. This anchors the ladder and prevents it from swinging sideways under lateral forces.

It is possible to climb a ladder in various ways which differ according to its shape and construction. Some of these methods are more secure than others; some, e.g. ascending a vertical ladder, could result in a fallen climber, while others, e.g. ascending a polycarbonate or extruded aluminium ladder, are inherently more secure since they allow the climber to maintain contact with the ladder (and the ground) throughout their entire ascent.

These methods of climbing ladders are:

The following techniques for ascending by hand may be used to cross a gap between feet or steps.

Care should be taken when using these techniques, as if there are insufficient handholds at the top of a ladder you may find yourself falling off and injuring yourself.

Conclusion: Always use a safety belt, and be sure to use the correct method for crossing an extension ladder gap.

A ladder may be used by more than one worker at once, if it can safely support them all. To do this, you must adjust the size of both the ladder and the distance between rungs to suit the number of workers, their weight, and any load being carried on the ladder.

Two workers side by side must have adequate room to work comfortably; each should be able to secure himself with his hands while doing work. If working on a roof or other area where you might lose your balance or fall off, you may need a restraining device such as scaffold clamps or safety belts.