What is the recommended ladder setup angle for portable ladders?

• A. Approximately 60 degrees
• B. Approximately 90 degrees
• C. Approximately 75 degrees (4:1 rule: for every 4 feet of height, place base 1 foot out)
• D. Approximately 30 degrees

Answer: (C)

A safe portable ladder setup uses about a 75-degree angle, which comes from the 4:1 rule: for every 4 feet of ladder height, place the base about 1 foot away from the wall. This angle keeps the ladder’s weight and center of gravity over its feet, maximizing friction at the feet and reducing the risk of the ladder slipping or tipping. It’s a practical compromise between a ladder that’s too vertical (which can topple backward and be hard to maintain) and one that’s too shallow (which places the climber too far from the wall and makes it unstable). The options of a near-vertical (90 degrees), or far too shallow (60 or 30 degrees), do not provide that stable balance and increase fall risk.