Sign Language interpreters typically work no more than two hours alone.
An increase in repetitive stress injuries among interpreters as well as deteriorating quality of translation after one hour's work resulted in a nation-wide standard of 2-hour maximums for interpreters. In most postsecondary programs an interpreter can work alone for an hour to an hour and a half. For any class longer than an hour and a half, two interpreters working as a team is typically required. They sometimes work in twenty-minute or thirty-minute turns. Team interpreting also provides a backup for when one interpreter misunderstands, misses, or needs an immediate break.