Mechanical Support for Ceiling Fans

I think your looking at the symptom not the root cause of the problem. If, you have to bear with me for a minute here, the bolt can support the weight of the fan, why should it come loose? What is different about a ceiling fan that we don't see, say on a car tire?

OK, everybody jump in here. I think it's the vibration of an unbalanced fan. If the fan was indeed truly balanced, there would be little or no vibration working on the bolts to loosen them. If we can't balance the fan, why not locking nuts?

I just don't think we need to go out and change all the bolts in the world to great big huge things as the almighty fix.

Right size the bolts, fix the vibration, and they'll stop falling off the ceiling.

Do you know of any instances of a ceiling fan falling off of a ceiling?

Change the bolts, add locking nuts and washers, but also add a chain(s) or cable(s) to support the thing above peoples heads just in case it does get free, with a microswitch to remove power instantly when it does that also puts a short across the power connection to the fan, to stop it dead in its tracks.....!

Its called Dynamic Braking if I remember correctly, works fantastically on practically any motor, AC, DC or Universal.