Which term describes an undiscovered performance problem whose adverse consequences only become evident when combined with other factors?

• A. Latent error
• B. Active error
• C. Near miss
• D. Hazard

Answer: (A)

This describes a latent error. A latent error is a hidden problem in the system—such as a weak procedure, flawed equipment design, or organizational gap—that isn’t apparent as harm on its own. Its adverse consequences surface only when other factors line up, like human error, high workload, or equipment failure, triggering an incident. This idea fits Reason’s model of how accidents occur, where latent conditions lay dormant like holes in Swiss cheese until an active failure aligns with them.

Active error, by contrast, is the direct mistake or unsafe action by a person that causes harm at the moment. A near miss is an event that could have caused harm but didn’t, often due to luck or timely intervention. A hazard is a potential source of harm that could cause injury or damage, not an undiscovered problem that requires a combination of factors to manifest.