In article s.com,
Taylor wrote:

They have tools out there to stop the water from flowing. Check out
www.quickstoptool.com. By the time the fire department gets there,
locates your main water shut off valve and the system drains, you will
have plenty of damage inside that could be avoided if you have a shut off
tool on hand. Since most sprinklers are serviced, a malfunction is
unlikely, its vandalism (whether intentional or not) that a lot of times
causes unnecessary damage. As I say all of this, the benefits to having
sprinklers outweighs the risk of potential damage. But for peace of mind,
there are tools out there that anyone can use. And if I was living on the
bottom floor, I would buy my neighbor one who lives above me incase their
sprinkler head gets damaged.

You might check in with the local fire inspectors. It has been about
30 years since I dealt with residential sprinklers (and even then only
peripherally) but it sticks in my mind that the first responders just
used a wooden shim like you use to level windows. I could be VERY wrong,
though.
--
America is at that awkward stage. It's too late
to work within the system, but too early to shoot
the *******s."-- Claire Wolfe