A ladder is a ladder is a ladder . . . right?
Actually, nothing could be farther from the truth, especially when it comes to portable ladders. There are two primary categories of portable ladders on the market, and each category is comprised of two or more specific types of ladders.
Portable ladders are also manufactured from different materials, in various lengths, and with different load capacities. We will cover all of these variables in future toolbox talks. But today we will start by identifying some of the most common types of portable ladders, as well as how to identify their maximum load rating.
The first general category of portable ladders are what’s known as self-supporting ladders (examples below). These portable ladders can hold themselves in an upright position when properly erected, and include regular step ladders (also known as fold-out ladders), plus most types of specialty ladders, such as two-way ladders, articulated ladders, and platform ladders. The other general category of portable ladders is what’s known as non-self-supporting ladders, because they have to be leaned against a wall or other solid surface to stand. These include single ladders and extension ladders.
All of these types of portable ladders have different uses, which we will discuss in upcoming toolbox talks. But portable ladders also have different capacity ratings. Ladder manufacturers communicate the maximum working load limit and duty rating of their portable ladders by attaching a sticker on one, or both, side rails of their ladders (refer to below for examples). Here is an overview of the working load limits that are assigned to various portable ladders:
Type III - Light-Duty Portable Ladder - For users requiring a maximum 200-pound working load or duty rating. For use on an occasional basis, such as general household use. Some state OSHA regulations (like California) actually prohibit the use of a Type III light-duty portable ladder at any work site.
Type II - Medium-Duty Portable Ladder - For users requiring a maximum 225-pound working load or duty rating. Common use by some commercial painters, in office settings, and for light maintenance work. Most medium-duty portable ladders must not be used with ladder jacks or scaffold planks.
Type I - Heavy-Duty Portable Ladder - For users requiring a maximum 250-pound working load or duty rating. Commonly used in factories and industrial settings, for utility work, and at construction sites.
Type IA – Extra Heavy-Duty Portable Ladder - For users requiring a maximum 300-pound working load or duty rating. Commonly used in factories, industrial settings, for utility work, and construction sites.
Type IAA - Special-Duty Portable Ladder - For users requiring a maximum 375-pound working load or duty rating. Also used in factories, industrial settings, for utility work, and at construction sites. It is important to know the working loads stated above includes not just the ladder user’s weight, but also the weight of clothing, PPE, tools, materials, and anything else carried or placed onto the ladder. So take the time to calculate the total weight of everything before you climb onto a portable ladder.
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