Which pair correctly lists the two main spray gun classes used for applying coatings?

• A. Airless and air-assisted spray guns
• B. HVLP and electrostatic spray guns
• C. Suction feed and pressure-feed spray guns
• D. Gravity feed and siphon feed spray guns

Answer: (C)

Coatings are applied using spray guns based on how the coating is delivered to the nozzle. The two broad classes are suction feed (also called siphon/gravity feed) and pressure-feed.

In suction feed, the coating comes from a cup or pot positioned below the gun; the atomizing air draws the coating into the air stream. This setup is simple and cost-effective, and works well for lighter to medium viscosity coatings with quick cleanup. However, it can struggle with thicker materials and high-production speeds because the supply to the gun is limited by gravity and suction.

In pressure-feed, the coating is pushed to the gun under pressure from a pressurized pot or line. This allows thicker, more viscous coatings to be sprayed and provides steadier, more controllable flow—ideal for higher build coatings and production work. The trade-off is more complex equipment and maintenance.

Other pairings in the options mix categories such as how the coating is atomized (airless, HVLP) or describe different feed arrangements that are not the primary two feed-based classes. Gravity feed is a type of suction feed, so it isn’t the distinct two-class contrast.