They don't have sprinklers anywhere at Bullworth. I think Rockstar made water come out of the lights to make it look that way. If you ask me, it was a really lame attempt. If they wanted to, they could have installed sprinklers in the gym. Ceiling height isn't really a factor.
By the way Mercury, I have a sprinkler from France sitting on a shelf in my house. It's made by "Rolland Arroseurs"