How often is is safe to shampoo your carpets?

I was wondering if you can damage your carpets and/or floor by shampooing too much. If so how much is too much? Is once a month too much?How often is is safe to shampoo your carpets?
I work at a kids playbarn type thing and we shampoo the carpets once a month. As it is a children's environment, obviously we need to be super careful about everything, but it's fine and we've been doing it for about 3 years!How often is is safe to shampoo your carpets?
no, that is ok....as long as you dont have a hardwood floor underneath.....and you suck out as much water as you can!
you can't shampoo your carpet to much once a month is fine