Final answer:
The application for a certificate of waiver must be submitted either 48 hours before travel or at the departure gate, depending on the airline's regulations.
Step-by-step explanation:
When preparing to travel with an assistance animal such as a Seeing Eye-certified or other officially trained dog, it is important to be aware of the specific documentation that may be required by the Department of Transportation (DOT) and the airlines. The DOT has established regulations that require forms to attest to the animal's health, behavior, and training. While some airlines may request these forms to be submitted 48 hours before travel, others may require them at the departure gate. It is typically straightforward for a passenger to provide these forms when their animal is officially trained and certified.