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Education and training are absolutely vital to the safe and successful use of Positive Pressure Ventilation and Positive Pressure Attack.

“Positive Pressure Attack for Ventilation & Firefighting” by Garcia, Kauffman and Schelble

Book Offer:

We now offer a complimentary copy of the book “Positive Pressure Attack for Ventilation & Firefighting” by Garcia, Kauffman and Schelble to customers who order VENTRY Fans for fire/rescue applications. Limit one per department.

Ventilation Resources, Articles and Responses

Published materials on ventilation are mentioned below. Further down this page, we also list additional Resources and link to Articles.

Positive pressure ventilation and attack (PPV and PPA) are regularly addressed in the media and we highlight and respond to some of the points here in hopes of minimizing misinformation and encouraging proper education.

1. Evaluating Positive Pressure Ventilation In Large Structures: School Pressure and Fire Experiments
(National Institute of Standards and Technology, Fire Research Division, July 2008)

VENTRY Fans were included in these experiments involving large PPV blowers. The NIST has made DVDs regarding their ventilation research available upon request. Visit www.fire.gov for these and other great research resources.

2. Interior Attack Needs New Thinking
(National Fire & Rescue magazine, July/August 2008, retrieved 8-26-2008 from nfrmag.com)

Kudos to Chief Dan Jones of the Chapel Hill (NC) FD for his recent editorial in National Fire & Rescue magazine. He wrote,

“Recognizing the containment capacity of building materials and the high heat and toxic smoke produced by today’s contents makes ventilation as high a priority as getting an attack crew inside. Aggressive interior attacks must be linked with equally aggressive ventilation tactics to reduce danger and increase the potential for a successful outcome. If you don’t have the means to ventilate, then you don’t have the means to conduct interior operations either.” [emphasis added]

3. Carbon Monoxide Levels
(Fire Engineering magazine, Nov 26, 2007, retrieved 11-28-2007 from www.fireengineering.com)

In the Fire Engineering article “PPA: Questions and Answers,” Garcia and Kauffman address carbon monoxide concerns during PPA and PPV and adeptly point out...

“During a structure fire, the CO level is already more than 1,000 ppm in most interior fires. The blower will reduce this level almost immediately and, during most operations, will continue to operate with a CO level near 100 ppm, which, although not good, is much better than 1,000 ppm. When the fire attack is over, taking the time to deploy electric blowers can be done.” (Retrieved November 28, 2007)

We must add, however, that if you use a VENTRY Fan, CO levels will drop to less than 35ppm -- well below OSHA warning levels! With adequate exit for the air, equilibrium levels of all VENTRY Fans are between 17 and 35 ppm. After the initial attack, instead of grabbing the elctric blower, just turn the VENTRY around and use negative pressure to remove any last remaining CO. (Click for more on CO)

4. Wheels and Shrouds on PPV Fans
(Fire Chief magazine, Sept 2007, retrieved 8-26-2008 from firechief.com)

In the September 2007 Fire Chief article “The Power of Positive Pressure,” we would like to address the section, “What to look for," in which specific features to look for in PPA and PPV blowers are listed. Most of these are valid considerations when choosing a blower, including:

  • Blowers should be gasoline-powered for a rapid deployment
  • Blowers should be able to tilt up and down to increase their ability to cover an opening if the optimum distance (8-10 feet) between the blower and opening can't be achieved.
  • The power plant of the blower should be as simple to operate as possible. The fewer switches the better.

It is not accurate to say, however, that “blowers should have pneumatic tires to facilitate one firefighter being able to maneuver it to the objective.” Our larger fans benefit from pneumatic tires but our most popular 20-inch VENTRY Fan is built light enough for one person to carry without the need for bulky, expensive pneumatics. Solid rubber wheels, standard on several of our larger fans, are also convenient because they are not subject to flats.

With all due respect, the recommendation that blowers should be shrouded is definitely not true. Contrary to this advice, shrouds on blowers do not “...increase the amount of air entrained and therefore the amount of exiting CFMs.” This is easily observed.

The outer quarter of a propeller does three quarters of the work. (Consider how far the tips travel in one rotation versus the center of the prop!) Blocking the air at the tips with a shroud starves the prop tips of air and dramatically increases noise. To see for yourself, hold your hand flat near the outer edge of a running VENTRY Fan’s free-flow guard. As you move your hand closer to the prop, the noise level will increase, because you starve the prop of air. If your hand makes that big a difference, imagine what a 360-degree shroud does!

Click here to see more on shrouds, including a true story that illustrates this point.

RESOURCES

All the points we have made here are minor. Thanks to the article authors and their sponsor for the educational advances they have made regarding positive pressure’s benefits. Detailed sources are below. Additional Resources are available on our links page. Please click here.

University of Texas, Austin (UT) and the Austin Fire Department (AFD). "Positive Pressure Ventilation, Training and Research.” <http://fireventstudy.com/> February-15-2008 (Date of access). Also available at <http://www.me.utexas.edu/~ezekoye/rsch.dir/PPV.html>

Kerber and Madrzykowski. "Evaluating Positive Pressure Ventilation In Large Structures: School Pressure and Fire Experiments.” PDF File (PDF file) <http://fire.nist.gov/nfrlpubs/fire08/art016.html> August-26-2008 (Date of access).

Ezekoye, Svensson & Nicks. “Investigating Positive Pressure Ventilation.” (<http://www.me.utexas.edu/~ezekoye/rsch.dir/documents/TravisHouseStudy.pdf>
March-3-2008 (Date of access).
Click here for some highlights we pulled from this paper.

Nicks, Watson, and Ezekoye. “Testing Tactics Scientifically: PPV in Residential Structures.” <http://www.me.utexas.edu/~ezekoye/rsch.dir/PPV.html> Presented April 2005 at FDIC 2005. October-6-2005 (Date of access).

City of Phoenix. “Positive Pressure Ventilation.” Last modified 7/10/2002. <http://phoenix.gov/FIRE/20212d.html> October-6-2005 (Date of Access). This is part of the “Phoenix Fire Department Operations Manual, Volume 2,” which is available in total at <http://phoenix.gov/FIRE/start_here.html>

Kerber and Walton. “Effect of Positive Pressure Ventilation on a Room Fire.” (PDF file) March 2005. <http://fire.nist.gov/bfrlpubs/fire05/PDF/f05018.pdf> Sponsored by the US Department of Commerce, US Department of Homeland Security, and the Federal Emergency Management Agency (FEMA). October-6-2005 (Date of Access).

The Building and Fire Research Laboratory section of NIST (National Institute of Standards and Technology) has conducted quite a few studies on PPV. Recent tests included VENTRY Fans. Please see www.bfrl.nist.gov and search for Positive Pressure Ventilation. DVDs of the research are also available through fire.gov

Garcia, Kauffman and Schelble, fire fighters from Utah who study, train, and publish a great deal on positive pressure attack and ventilation. They maintain the website positivepressureattack.com.

ARTICLES LISTED

Here are links to articles on PPA and PPV:

Additional Resources are available on our links page. Please click here.


Good, bad, or otherwise, we appreciate your feedback on this website! J. Neils Enterprises, Inc. - Home of All-Terrain Air, Power and Light. 888-257-8967. J. Neils Enterprises is located on Hauser Lake in Hauser, Idaho Copyright 2007 J. Neils Enterprises, Inc. All Rights Reserved