Container Requirement 1 (CR1)
The IATA container specification for dogs and cats in the hold: rigid materials, metal door, bolted halves, ventilation, and room to stand, turn and lie down. No crate is pre-approved: the airline checks yours at the counter.
This is the standard airlines apply to a crate for the hold, and its parts are specific: rigid crate in hard plastic, wood or metal, solid roof, metal door, ventilation on at least three sides, and four on many international routes, the two halves closed with nuts and bolts rather than clips, wheels removed or blocked, and enough room for the dog to stand upright, turn around and lie down naturally. The label matters less than it looks: no crate is pre-approved, so 'IATA-approved' printed on the box is marketing. The airline checks the crate against the rules at the counter, with your dog inside it.
Guides that use this term
Gear & stores
Airline-approved dog crates: what the IATA rules actually require
Before buying a hold crate, what IATA Container Requirement 1 demands: rigid materials, ventilation, and sizing measured on your dog, not the label.