Static Pressure (SP) is best described as

Static Pressure (SP) is best described as

• A. The potential energy of the ventilation system
• B. The pressure exerted by air in motion, always positive
• C. The sum of VP and SP
• D. The amount of air flowing through the duct

Answer: (A)

Static pressure is the energy per unit volume that air has due to its position inside the duct; it’s the pressure that could do work on surroundings if the air weren’t moving. In other words, it’s the potential energy of the air in the ventilation system. This is different from the pressure caused by the air moving (dynamic or velocity pressure) and different from total pressure, which is the sum of static and velocity pressure. The amount of air flowing through the duct is determined by flow rate, not static pressure.

Static pressure is the energy per unit volume that air has due to its position inside the duct; it’s the pressure that could do work on surroundings if the air weren’t moving. In other words, it’s the potential energy of the air in the ventilation system. This is different from the pressure caused by the air moving (dynamic or velocity pressure) and different from total pressure, which is the sum of static and velocity pressure. The amount of air flowing through the duct is determined by flow rate, not static pressure.