Air France-KLM, British Airways and Lufthansa are the safest airlines in Europe, according to a study ranking the "ten safest airlines" by the Air Transport Rating Agency (ATRA) released Monday.

The safest U.S.-based airlines are AMR Corporation, Continental Airlines, Delta Airlines, Southwest Airlines, United Airlines and US Airways, while the safest from Asia is Japan Airlines, it said, without giving a ranking within the top ten.

To obtain this classification, the first of its kind, ATRA examined publicly available information on 15 criteria, such as the average age of the aircraft used or the homogeneity of the fleet, it said.

The agency explained that to understand airline safety, one needed not only to look at accident figures, but also "technical, human, organisational and external" elements.

"Even though the European Union publishes a 'blacklist' of dangerous airlines, there exists a real difference in safety between the other airline companies," ATRA added.

World's 10 Safest Airlines (in alphabetical order):

Air France-KLM

AMR Corporation (American Airlines, American Eagles)

British Airways

Continental Airlines

Delta Airlines

Japan Airlines

Lufthansa

Southwest Airlines

United Airlines

US Airways