Ladders are built from one of three basic materials; wood, fiberglass, and metal (aluminum).
The environment of your work site is the first factor in choosing the material from which your ladder is constructed. For example, if you are working near sources of electricity, a metal ladder should be rejected since aluminum is an electrical conductor. Your body can complete an electrical circuit between the electrical power source, the ladder, and then to the ground in the event of a live wire contact incident. An electrical shock while working from a ladder can trigger a fall or cause your heart to stop leading to serious injury or death. On the other hand, if there are no electrical power sources in your work area, the aluminum ladder is the lightest weight when compared to fiberglass or wood.
There are also several kinds of ladders manufactured for a variety of uses. Again, evaluation of your work environment and knowledge of what ladders are available will allow you to choose the right ladder for the job. Each of the following considerations addresses safety issues in your work environment:
- Will the ladder be resting on an uneven surface?
- Is the work area crowded with people and/or materials?
- What obstructions are in the path of the climb?
Next, the proper ladder length must be selected. It is unsafe to use a ladder that is too long or too short. When using a Step Ladder, for example, standing on the top cap or the step below the top cap is not permitted due to the increased likelihood of losing your balance. Likewise, when using an Extension Ladder, the top three rungs are not to be used for climbing. A Straight Ladder is too long, for example, if ceiling height prohibits the ladder from being set-up at the proper angle. Likewise, an Extension Ladder is too long if the ladder extends more than 3 feet beyond the upper support point. In this case, the portion of the ladder that extends above the upper support point can act like a lever and cause the base of the ladder to move or slide out. Safety standards require a label on the ladder to indicate the highest standing level.
Next, consider the Duty Rating of the ladder. This is an indication of the maximum weight capacity the ladder can safely carry. To figure out the total amount of weight your ladder will be supporting, add:
- Your Weight; plus
- The Weight of Your Clothing and Protective Equipment; plus
- The Weight of Tools and Supplies You Are Carrying; plus
- The Weight of Tools and Supplies Stored on the Ladder
There are five categories of ladder Duty Ratings:
- Type IAA (Extra Heavy Duty) 375 pounds
- Type IA (Extra Heavy Duty) 300 pounds
- Type I (Heavy Duty) 250 pounds
- Type II (Medium Duty) 225 pounds
- Type III (Light Duty) 200 pounds
The Duty Rating of your ladder can be found on the specifications label. Safety standards require a Duty Rating sticker to be placed on the side of every ladder. Do not assume that a longer ladder has a higher weight capacity. There is no relationship between ladder length and weight capacity.
Types of Ladders
Your work environment, including the physical size restrictions, is probably the most important factor in determining the type of ladder to use for a given job. The versatility of the ladder, however, is a major consideration, especially for domestic use. Otherwise, the number of ladders that one would need to have available for the wide variety of tasks around the home that require elevation from the ground would be prohibitive.
In an effort to assist in familiarizing yourself with the standard ladder types that are available, consider the following:
A description of the Proper Care & Use, Proper Set-Up, Safety Labeling, and the identification of the governing ANSI safety standard for each type of ladder follows.