In the United States non-passengers were once allowed on the concourses to meet arriving friends or relatives at their gates , but this is now greatly restricted due to the terrorist attacks . Non-passengers must obtain a gate pass to enter the secure area of the airport . The most common reasons that a non-passenger may obtain a gate pass is to assist children and the elderly as well as for attending business meetings that take place in the secure area of the airport . In the United States , at least 24 hours notice is generally required for those planning to attend a business meeting inside the secure area of the airport . Other countries , such as Australia do not restrict non-travellers from accessing the airside area , however non-travellers are typically subject to the same security scans as travellers
terrorist attacks
September 11 attacks
Airport security