What is the difference between leading and lagging safety indicators in an airport SMS?

• A. Lagging indicators reflect past safety performance.
• B. Leading indicators measure financial performance.
• C. Leading indicators assess past safety performance.
• D. Leading indicators predict and prevent incidents; lagging indicators reflect past safety performance.

Answer: (D)

Leading indicators are proactive measures that help prevent incidents by signaling where the safety system may be challenged before anything occurs. In an airport SMS, they focus on activities and conditions that reduce risk, such as hazard identifications, completed risk assessments, timely corrective actions, quality safety training, near-miss reporting, and the frequency of safety observations. The aim is to predict potential failures and take action to stop them from becoming events.

Lagging indicators, on the other hand, look backward at what already happened. They reflect the outcomes of safety performance, like injury or illness rates, actual incidents, property damage, or regulatory findings. They tell you the results of past safety efforts rather than forecasting future risk.

So the best statement is that leading indicators predict and prevent incidents while lagging indicators reflect past safety performance.