JERROLD J. SCHARNINGHAUSEN, Ph.D.
Directorate of Assessments and Prevention
Workplace Safety Division
U.S. Army Combat Readiness Center
Fort Rucker, Alabama
Falls are a leading cause of accidents in the workplace, and ladders are involved in a high percentage of these incidents. The Occupational Safety and Health Administration reports that each year nearly 300 people die from ladder-related injuries. The estimated annual cost of these injuries in the U.S. is $11 billion, including work loss, medical, legal, liability, and pain and suffering expenses. Among workers who missed work due to occupational ladder accidents, the average case involved 11 days of lost time. Almost one-third of those cases involved missing 31 or more days of work. Like other types of accidents, fall and ladder-related accidents are preventable by following basic guidelines.
Choosing the right ladder
The first rule of choosing the right ladder is to use a ladder. Too often, people just grab the closest thing to them and end up standing on buckets, boxes or chairs instead of taking a few minutes to get a ladder. So which ladder do you need? When selecting a ladder, you need to ensure it is tall enough for the job. According to the American National Standards Institute (ANSI), ladders are marketed and sold by the total height, or the total section length, not the usable height. You should be no more than 4 feet off the ground if you are using a 6-foot ladder. You will need the top 2 feet of the ladder to hold onto to maintain three points of contact (discussed later in this article). Never stand on the top rung or use the top step of a stepladder (or A-frame).
Extension ladders are sold by the total length of the sections. It will only mention the 3 feet of overlap in the fine print. A 20-foot extension ladder is two 10-foot sections, but because of the needed overlap, it is only 17 feet tall. If you are using it to climb onto a roof, you should have 3 feet of ladder above the roofline to give you something to hold onto as you transition on and off the ladder. This means that a “20-foot” extension ladder is only good to safely gain access to a roof 14 feet in height. Given all these factors, you almost always need a ladder taller than you think is required. Make sure the weight rating of the ladder you choose is greater than your weight and all of the clothes, tools and equipment you will be wearing/carrying. A duty rating of I, IA or IAA should be more than adequate for most projects. See Table 1 below for ladder weight ratings.
When using any ladder, be aware of your surroundings and never use an aluminum ladder when working on or near electricity. Use a fiberglass ladder if there's any chance you could be working with electrical wiring or near power lines. Remember that metal and dirty or waterlogged wood can also conduct electricity. Aluminum is lighter, while fiberglass is stronger but heavier.
Standing on the top rungs or overreaching can create an unsteady platform, leading to an accident. Stay off the top two rungs of a stepladder, and the top three rungs of an extension ladder. If you're deciding between two ladder heights, opt for the taller one to give yourself some leeway.
Using a ladder
Before using a ladder, inspect it to confirm it is in good working condition. Ladders with loose or missing parts must not be used. Rickety ladders that sway or lean to the side should also be rejected. If the ladder is damaged, do not use it. Ladders are built with a 4-to-1 safety ratio, meaning a ladder rated for 250 pounds was tested to hold 1,000 pounds. Don’t assume that your ladder will support that weight, as the ladder is tested to specific parameters but not under every possible condition and angle. If the rungs or side rails are bent, broken, cracked or split, there is no way to determine what that ladder is still capable of supporting.
One step many people miss during the inspection is to check the feet of the ladder. The feet are made of soft material and have tread like the tires on your vehicle. If the tread is worn, the ladder should not be used until it is replaced. Care also needs to be used when positioning your ladder. Put the base of a ladder too close to a building and it could tip over backward; too far away and it could slip out from under you. When positioning the ladder, follow the 4-to-1 rule: For every 4 feet of ladder height, the base should be 1 foot from the wall. Ensure that extension ladder rung locks are secure and the fly section (the top portion) is slid in front of the base (the lower section) before climbing. For stepladders, fully extend the rail spreaders.
Ladders should be set on firm, level ground. Never use rocks, bricks or boards to level a ladder. Instead of building up the low side, dig out the high side for proper setup. Always face the ladder when using it and never carry any tool or equipment that might cause you to lose your balance. Heavy tools and equipment should be raised using a rope or lift. These rules are to help the climber safely ascend and descend the ladder.
If you are working from a ladder, make sure you lean your leg or hip into it to maintain balance. The most important rule of ladder use is to keep your body between the side rails. Never overreach. If you can't reach something without leaning outside of the side rails, climb down and move the ladder. Losing balance while overreaching causes almost all disabling or fatal accidents.
Do not use ladders in high winds or storms. One strong gust could send you crashing to the ground. Also, wear clean, slip-resistant footwear. Shoes with leather soles are not appropriate for ladder use since they are not considered sufficiently slip resistant. Never place a ladder in front of closed doors that can open toward the ladder. The door must be blocked open, locked or guarded.
Factors contributing to falls from ladders include haste, sudden movement, lack of attention, the condition of the ladder (worn or damaged), the user's age and/or physical condition and the user's footwear. Although the user's weight or size typically does not increase the likelihood of a fall, improper climbing posture creates an imbalance and may cause a fall. Reduce your chances of falling during the climb by climbing slowly and deliberately while avoiding sudden movements; never attempting to move a ladder while standing on it; and keeping the center of your belt buckle (stomach) between the ladder side rails when climbing and while working. Do not overreach or lean so that you don't fall off the ladder sideways or pull the ladder over sideways while standing on it.
The three-point-of-contact climb
The safest way to climb a ladder is to utilize three points of contact because it minimizes the chances of slipping and falling from the ladder. At all times during ascent, descent and while working on the ladder, the climber must face the ladder and have two hands and one foot, or two feet and one hand, in contact with the steps, rungs and/or side rails. Using this method, the user is not likely to become unbalanced in the event one limb slips during the climb. Never carry any objects in either hand that can interfere with a firm grip on the ladder or it will increase the chance of falling in the event a hand or foot slip occurs.
Accidents can happen for many reasons, but most can be prevented. Some of the major causes common in almost all accidents are not using the right tool for the job, failing to inspect the tool for damage and not following the basic safety guideline(s) for that tool. Follow this simple guidance when working with a ladder and most problems can be avoided.