wow I think there are a lot of factors at work here - how old? Personality? When was the last time they ate etc. I've kept my buddy out for 30 - 45 minutes at one time but I'm not sure of the standard or anything. I've read of people watching a movie with their snakes so I'm assuming you can keep your snake out for an hour or so but again it depends on how old, or rather how easliy stressed the snake is .. If it starts to get stressed, best just to put them back home.