Fog master streams are generally operated at what nozzle pressure?

Fog master streams are generally operated at what nozzle pressure?

• A. 80
• B. 100
• C. 150
• D. 200

Answer: (B)

Fog master streams are designed to deliver large volumes with a broad, cooling pattern, and they perform best when the nozzle pressure is around 100 psi. This pressure gives a stable, wide fog that reaches effectively and provides the cooling needed for interior fires without overwhelming the operator with force. If the pressure drops to about 80 psi, the pattern can become coarser and the reach and cooling capability diminish. Pressures much higher, like 150 or 200 psi, increase nozzle reaction and tend to narrow the spray, reducing the wide fog effect the master stream is designed to produce. So, 100 psi is the standard, optimal setting for fog master streams.

Fog master streams are designed to deliver large volumes with a broad, cooling pattern, and they perform best when the nozzle pressure is around 100 psi. This pressure gives a stable, wide fog that reaches effectively and provides the cooling needed for interior fires without overwhelming the operator with force. If the pressure drops to about 80 psi, the pattern can become coarser and the reach and cooling capability diminish. Pressures much higher, like 150 or 200 psi, increase nozzle reaction and tend to narrow the spray, reducing the wide fog effect the master stream is designed to produce. So, 100 psi is the standard, optimal setting for fog master streams.