Which of the following is a valid set of spray gun classes used in coatings application?

• A. Brush and roller
• B. Dip and spray
• C. Roller and mastic gun
• D. Suction feed and pressure-feed spray guns

Answer: (D)

The key idea is how spray guns are categorized by how the coating is delivered to the nozzle. The two main spray gun classes in coatings application are suction (siphon) feed and pressure-feed spray guns. In suction feed, the fluid is drawn up into the gun by air flow from a cup below or attached to the gun. In pressure-feed, a pressurized container pushes the coating into the gun for delivery. These two are valid spray gun classes because they describe the actual methods used to feed the coating to the nozzle.

The other options mix tools or methods that aren’t spray gun classes—brush and roller are hand-applied tools, dip is a immersion process, and a mastic gun is a caulking-type tool, not a spray gun class.