Ventilation Calculators

Each calculator solves for whichever value you leave blank.

Basics

• Volumetric Flow Rate
• Velocity and Velocity Pressure
• Total Pressure
• Continuity (Conservation of Mass)

Hoods

• Hood Flow from SPh
• Hood Static Pressure
• Hood Entry Loss
• Coefficient of Entry

Ducts

• Energy Balance (Bernoulli)
• Resultant Velocity Pressure at a Junction
• Balancing a Junction (Corrected Flow)

Fans

• Fan Law 1 (Flow)
• Fan Law 2 (Pressure)
• Fan Law 3 (Power)
• Fan Total Pressure
• Fan Static Pressure

Concentrations

• Effective Ventilation Rate
• Air Changes per Hour
• Dilution Air for an Evaporating Liquid
• Concentration Buildup from Zero
• Concentration Buildup or Decay with Generation
• Purge (No Generation)
• Steady-State Concentration
• Hummel Evaporation (Generation) Rate

Hood types

• Slot Hood
• Flanged Slot Hood
• Plain Opening Hood
• Flanged Opening Hood
• Booth
• Canopy Hood
• Plain Multiple-Slot Hood
• Flanged Multiple-Slot Hood

For estimation only. Not a substitute for a qualified engineering design.