2. Warm-up: Listening

In Unit 7a, you read about a security incident at the airport. Basically, there were three parts who played a key role in it: the inspector disguised as a passenger, the security official and the walk-through metal detector. Surprisingly, it was the official, not the airport metal detector, that caused the incident. Very often, some incidents and even accidents do not happen due to a technology failure, but due to a human error. This time, the walk-through metal detector (WTMD) was fault-free. By reading a technical text, you have even had a chance to find out how it works, so now it should not be so difficult for you to watch the video at… and complete this listening comprehension task.