The Learned Hand Formula

The Learned Hand Formula is a way to evaluate safety and negligence by balancing risk, precaution, and potential harm. It suggests that negligence exists if the cost of taking safety measures (B) is less than the chance of an accident (P) multiplied by the potential damage (L). Mathematically, it's B < P × L. If protecting against a hazard costs less than the expected loss from an accident, safety measures should be taken. This helps courts and engineers decide when precautions are reasonable and necessary.