Ask the Expert Question-and-Answer Archive

by Ron Joseph

September, 2003

Applying Nitrocellulose Lacquers - Spray Booth Fires

Q. Fire safety: Is there any danger in applying nitrocellulose lacquers and oil alkyd enamels in the same spray booth. I thought I read some where that this could cause a fire hazard in relation to the lacquer sealing over the surface of the enamel stopping it drying properly and this may lead to spontaneous combustion.

A. In the days when nitrocellulose lacquers were the backbone of the painting industry, many spray booth fires were reported. As I understood it, an exothermic reaction took place while heavy buildups of the nitrocellulose were drying on spray booth filters. Eventually the temperature reached the autoignition point of the paper filters and fires started. The use of nitrocellulose paints together with other synthetic solvent-based paints also apparenrtly contributed to the problem.

I'm not sure how much of what I understood is true and scientific, nor did I pursue it since most of the industry was converting to other resin technologies. Essentially, the problem went away.

If you need to get more information on this, I suggest that you write to the manufacturers of nitrocellulose resins or refer to some of the older text books. If you do find an answer please let me know as I would like to be able to share the information with others.