IATA Container Requirement for cargo-area airplane crates
The International Air Transport Association (IATA) is an international trade group that represents “some 230 airlines comprising 93% of scheduled international air traffic.” Among other things, it publishes regulations for shipping live animals.
The “Container Requirement” for cargo-area airplane crates describes acceptable crate construction and labeling. It also describes how animals should be prepared for travel, and how they should be handled while they’re en route.
Your crate must meet the IATA requirements or it will not be accepted for shipping (the rules are there for a purpose — you have only to read some of the airline pet incident reports to appreciate how important it is to transport your pet in a really sturdy, well-made crate).