Now that's one hell of a story
For one thing, I never would have thought that the lacquer overspray dust would self ignite. I just sweep it up and never give it a thought. It makes sense, but I never gave it a thought.
When I first started woodworking, ny shop was less than a week old in a warehouse building. We were closing up later than normal and and my eyes started to burn. So did my girlfriends. We searched all over and could not find the source. Then I kicked a pile of old stain rags and it started to smoke. I quickly kicked it more to spread the rags out on the concrete floor. and problem was found and safely taken care of. I simply poured water on the rags and put them outside on top of the concrete.
Not even a year later, one day I heard this whoosh sound. I looked around and barely able to see a very light colored flame slowly creeping up a wall and then disappeared at about 4 or 5 feet from the ground. For a few seconds I was in a panic. I had 55 gal drums of nitrocellulous lacquer, lacquer thinner and Methyline Chloride. I wasn't even concerned about the lumber at that point. Anyway, there was no damage.
I always swept the floors everyday, just didn't give much thought to the dust on the walls. Now when I start cleaning up, I start blowing down with a leaf blower. I blow down the shelves, walls, overhead and finally the floors.
All of the above comments are greatly appreciated. It's been about 7 years since my last shop and when I get a new shop, I want to be prepared. When not doing something for a long while you tend to forget. At age 73 you tend to forget a lot more than when you were in your 30's.
Also note that the little wall mounted fire extinguishers are a lot better than nothing but not much to depend on once a fire gets going. I would suggest that when one of this gets past its expiration point, rather than just chuck it, actually use it to get the feel of one. You will be surprised at how fast it empties out. Its OK for a trash can fire, but if its lumber or chemicals, use it to head for the door and get out.
Hope we get some more first hand stories.