Review of Ventilation Principles & Practices

This in-depth, monthly MFRI firefighter drill helps readers understand the principles of ventilation, including the various types and tools needed.

  4. Tactic used to save rest of structure by cutting firebreak in roof.

D. Hydraulic Ventilation

  1. Use of interior fog stream to move smoke and gases through window or door

  2. Wide fog pattern utilized approximately two foot from opening.

  3. Fog pattern must cover 90% of opening for maximum effect.

  4. Will move more air than smoke ejector

  5. Quick way for attack crew to start ventilation process

  6. Will increase water damage

E. Mechanical Ventilation

  1. Negative Pressure (Use of smoke ejectors)

      a. Placement of ejector for maximum effect (highest point in opening)

      b. Reduce “churning”

      c. Remove items such as drapes, blind, screens, etc. which might block air flow.

      d. Provide and maintain unobstructed replacement air opening

  2. Positive Pressure (Use of PPV fans)

      a. Placement of PPV fan for maximum effect (outside -ground level)

      b. Cone of air to completely cover door opening

      c. Eject smoke from opening on opposite side of building

      d. May pressurize one room at a time by closing interior doors



Student Performance Objective (SPO):

The student will demonstrate a basic understanding of the principles of ventilation, the safety precautions to be taken when ventilating a structure and how to use the various types of ventilation through class discussion and participation.


Review of Ventilation Principles & Practices

   • Review of Ventilation Principles

   • Safety Precautions during Ventilation

   • Review of the various types of Ventilation