What is the ladder rule regarding how far you need to place the ladder from the wall should be?

• A. 4:1 ex. 16' ladder 4' from wall
• B. 3:1 ex. 20' ladder 6.7' from wall
• C. 2:1 ex. 12' ladder 6' from wall
• D. 5:1 ex. 20' ladder 4' from wall

Answer: (A)

The ladder safety rule to remember is the 4:1 rule: for every four feet of ladder height, place the base one foot away from the wall. This angle tends to put the ladder around a 75-degree lean, which is the commonly recommended safe stance.

Applied to the example, a 16-foot ladder should have its base about 4 feet from the wall. That fits the 4:1 guideline exactly, making it the best choice.

The other options don’t follow that 4:1 proportion. A 20-foot ladder with the base about 6.7 feet from the wall uses a 3:1 ratio, which changes the lean angle away from the recommended safe range. A 12-foot ladder with the base 6 feet out is a 2:1 ratio, making the ladder much too shallow and unstable. A 20-foot ladder with the base only 4 feet out misses the 4:1 ratio as well, yielding an angle that isn’t the standard safe lean.