Anthony Shaw, a security team leader in the airport’s hold baggage screening team, said staff often find devices including vapes, power banks and tablets in checked luggage.
“If the battery gets too hot, or is faulty, it can catch fire without warning,” he said.
Shaw said staff could screen almost 1,000 bags for a large long-haul aircraft and several hundred for a short-haul flight.
“Each bag that fails to pass security checks gets pulled aside, and often needs to be inspected manually,” he said.
“This can create delays, but it also creates a risk that your hold bag might not make it onto the plane at all.”
The CAA said a fire on board could result in an aircraft being diverted or evacuated.
Vapes, power banks and spare batteries must be carried in the cabin rather than placed in checked baggage.
The CAA advised travellers to check their airline’s rules before setting off because additional restrictions may apply.