Back in 2014, ABYC made a major improvement to H‑41, Reboarding Means, Ladders, Handholds, Rails, and Lifelines by extending the required ladder depth from 12 inches below the water to 22 inches for reboarding ladders.
Why the shift?
ABYC, with USCG support, tested boats using ladder depths from 12”–32”. The findings were unmistakable:
- Longer ladders give people better ergonomics, leverage, and control
- More control keeps limbs away from the propeller zone
- Increasing ladder length by just 10 inches reduced the chance of limbs entering the propeller area by ~75%
At the end of the day, it’s simple: keeping people away from the propeller is one of the most effective ways to reduce prop injuries. Longer ladders help make that happen.