If you see fire

And don't take the batteries out of the smoke detector so that you can have a crafty fag in the back room at work despite it being illegal.

This is good because with the poem you've also created characters. I can just see a little old lady reading the instructions in front of the alarm glass and getting very confused, or a polish immigrant, or a college professor who'd want to 'correct' it and make order of it rather than breaking the glass and raising the alarm. Yep, like this.