If a smoke detector in one's home goes off for no reason on Shabbos, making a tremendous noise, how should one act? Could one for example turn it off by throwing it off the balcony? Does the fact that it could make the fire service react for no reason create some license to at least break it to silence it?
Answer:
If it is movable [as it sounds from the question] it should be wrapped up in many blankets and put in a place where the noise will not be heard. Another possibility would to have a non Jew turn it off, preferably without directly asking him to do so, rather by hinting to him. If these are both impossible, and the noise is bothering a child, that child may be allowed to turn off the device which is for his own benefit.
Assuming the fire department are non Jews there would be no leniency to violate Shabbos to prevent their reaction.