Before Christmas I had prepared two pieces of cotton fabric with two different fire-resistant solutions: one was a mix of borax and boric acid, the other had a high concentration of alum. Today, I finally tested them. I expected the alum fabric to perform better under fire — the fabric was very stiff, it just seemed more heavy duty. Neither fabric burned, but the alum solution singed quickly. Although I nearly burned my own fingers the borax treated fabric just smoldered a little, smoked a little, then went out. Borax is the winner!
Here’s the borax recipe:
Dissolve 1/4 cup borax and 1/4 cup boric acid in 4 cups of warm water. Soak fabric to be treated, squeeze off excess water and line dry. Repeat procedure each time the fabric is washed. If the fabric cannot be soaked, apply this solution with a spray bottle. Left over liquid can be stored at room temperature.