Fire still spreads in underground labs

So I started I fire by one of (what I think is?) the swimming pools to clean off some of the filthy zombie gear and while I was doing the laundry the fire ended up spreading. Suddenly the entire floor of the lab was an inferno.
I thought that basements were considered fireproof according to the wiki, especially since the entire floor is concrete? The only thing that should’ve been flammable in the environment should have been possibly the railings, but other than that there was no furniture around…
This some sort of oversight in the coding?

i think that the only basements safe from that kind of situation, are the house basements

This is confusing, because almost all the rooms in Science labs are fireproof from my experience so far, with some exceptions like the restrooms with TV’s, fridges and so on, there was carpet I think and a lot of other stuff where the fire could spread throughout the room. But otherwise, for example, I always burn all the fungal stuff when I encounter it and I don’t even close the door for that particular room, all fungal burns down and no fire spreading anyway.

What kind of underground labs are you talking about where you are doing laundry?

Give some screenshots if you can, it would help to clear what’s up.

I’m talking about the areas with the large water tiles surrounded by rails in the lab escape scenario. The concrete floors and metal walls should be inflammable…
I don’t remember there being any fungi in the underground labs…