Ask the Expert Question-and-Answer Archive

by Ron Joseph

October, 2006

Spray Painting Without a Spray Booth

Q: What are some other methods, beside spray (gun) painting Best Practices, to reduce the level of overspray in a localized area?

The spray area is open..no booth, no true vetilation system (just some large blowers that exhaust to atmosphere).  At times, the volume of the spray overwhelms the area.

I have been told the system is "Grandfathered", and there is no requirement to rig the area properly... once one change is made, the entire ventilation system would have to be redone.

What are some methods to reduce the overspray exposure to non-protected personel?

A: Your email does not say how much paint you spray, but in my opinion you are playing with fire, literally and figuratively. Moreover, your employees are inhaling the vapors some of which might be carcinogenic or fall into what the EPA calls "hazardous air pollutants".   The most effective methods for reducing overspray is to properly set up the spray guns using the lowest usable fluid pressures and consequently also the lowest usable air pressures. Also, your painters need to be trained to follow proper painting techniques. The type of spray gun also makes a difference, with HVLP and electrostatic being more efficient than conventional.   Again, I strongly suggest that you provide your facility with a spray booth according to the provisions of National Fire Protection Association (NFPA) Bulletin 33.

Best wishes,

Ron Joseph