Health,
What do you do if your smoke detector went off at 3 am due to a fire???
Heaven forbid this should ever happen. In my mind, what would need to be done first is a rapid assessment of the situation. If there was a lot of smoke in the house, or the fire was R”L obviously large, I would not bother with trying to extinguish the fire at all – just get everyone out as fast as possible, keeping low to the ground while moving inside the house. No smoke, I think everyone should be woken up and get out while I run and get a fire extinguisher. If the fire is small, I’d try the extinguisher on it. If it was large (bigger than what I’d make in a backyard fire pit), I would get out.