Why do airport security screeners sometimes fail in covert tests?

This paper discusses covert testing data and key human factors. First, different reasons why airport security screeners sometimes fail to detect threats when covert tests are conducted at airports are discussed. Key human factors are identified and analyzed with regard to covert test results. It is explained that pre-employment selection and training are indispensable prerequisites for good operational performance of airport security screeners. However, they alone cannot guarantee that screeners react appropriately when tested with real threat items at a security checkpoint. Humans often fail if something happens that they do not expect. Therefore, it is recommended to conduct covert tests on a regular basis so that screeners become prepared and get trained to react appropriately. A recently conducted study on covert tests provides empirical evidence in favor of this view.