What type of nozzle is required to properly apply foam?

• A. Aerojet Nozzle
• B. Flat Fan Nozzle
• C. Fog Nozzle
• D. Solid Stream Nozzle

Answer: (C)

Foam works best when the water–foam solution is broken into a broad, fine spray so air can mix with it and form a stable foam blanket. A fog nozzle creates that many-branch, fine droplet pattern and entrains air as it discharges, which distributes the foam evenly over the surface and lets the foam expand and cling to the fuel or area being cooled. This wide coverage reduces runoff and helps the foam blanket form quickly, improving cooling and fire suppression.

Other nozzle types produce fatter streams or sheets that don’t entrain air as effectively, leading to poorer foam formation, uneven coverage, and less stable foam. That’s why the fog nozzle is the best choice for proper foam application.