Mopping the floor set the smoke alarm off

[Katemax82]

I mopped the kitchen floor this evening and the smoke alarm went off. Apparently this is a thing and everyone knows it. No I didn't open a window as it's dark outside. Am I wrong to think wtf?

Yes it’s a thing - to do with mopping vigorously creates water vapour which can let off the smoke alarm

washing my car sometimes sets off the house burglar alarm too

I have evidently never mopped 'vigorously' enough. 😂

I have never heard of this. Also clearly not a vigorous mopper.

scratch's head

Never heard of this I guess I need to pick up my mopping game

Do you use hot water to mop or chemicals? It’s nothing to do with mopping vigorously 🤦‍♀️

It must be coincidence

Is it boiling hot water you're using? A tiny bit of steam from my shower sets mine off

I mop every day. And I steam mop but I’ve never set off the fire alarm!

An excellent reason for women not to put much effort/energy into housecleaning!

Science lesson for the day..... (and I'm fully expecting someone to tell me I'm wrong 🤣)

Smoke alarms work by having a radioctive block, which very gradually decays as all radioactive stuff does. It's only very very slightly radioactive so can't harm you. Next to the radioactive block there's a small gap and sensor which detects the radioactivity across the gap, and completes the circit. As long as the sensor is detecting radioactivity it's happy, and the alarm remains off. If anything gets in the way of that gap, such a smoke particles from a fire, steam from a shower or steam from a floor mopped with boiling water, then the particles stop the detector from sensing the radioactivity, the circuit isn't complete and the alarm sounds.

After about 10 years the radioactive block has decayed so much the sensor can't reliably detect it. And that's why smoke alarms have a ten year life span. Because the radioactive block isn't radioactive enough!

Thank you all for listening to my TED Talk.

I’d get the alarm checked or replace it if it’s old.