Repair to extractor fan??

Spookily extractor fan kept on running an hour or so after switching off at switch, is there something I should do to ensure this doesn't happen again?
Sandra, October 2008


done
I KNEW THAT THIS CAME ON ITSELF AND DID NOT GO OFF FOR HOURS, PROBLEM HAS NOT HAPPENED AGAIN FINGERS X'D!!! THANKS ANYWAY

SANDRA, November 2008
Extractor fans in bathrooms often have a built in timer so that fan runs on, usually for 15 mins.

J, October 2008