Fsmt475 week 4 forum responses

#1

It is crazy to think that we have hit the half way point in class. Firefighting is all about asking questions and trying to find new things to make it safer or put the fire out quicker. The first question that I have is why is it taking firefighters getting trapped or killed for departments change the way they fight fires? There are so many classes out there that firefighters can take to understand modern fire behavior. I think it has a lot to do with the mind set of it will not  happen here or to us. Another question I have is what needs to happen to get builders to start using real materials when building modern homes that is not light weight? I ask this question because modern building construction is a big part of modern fire behavior and how fires spread. One more question I have is will firefighters be able to keep up with modern fire behavior or will firefighting as we know it just be get on scene and put water on the fire from the outside? A lot of departments are thinking of going this route to help protect their firefighters , there is the chance that someone could be inside and we as firefighters did take an oath to protect life and property. All of these questions deal with modern fire behavior and modern firefighting. good luck to everyone on everything due this week in class. 

#2

“Fire departments use ventilation blowers or fans to pressurize a structure prior to suppressing a fire. This pressurization or positive pressure ventilation (PPV) tactic has not been characterized carefully enough to establish specific guidelines for optimum use of PPV. PPV can assist in the venting of smoke and high temperature combustion products and make attacking the fire easier than without PPV. However, this tactic also provides additional oxygen to the fire and can increase the rate of heat and energy being released” (Kerber, Walton, 2005).  The result of adding extra oxygen to a fire at the wrong time or in an uncontrolled fashion could result in an extremely dangerous fire event.

Further evaluation, study, and experimentation needs to be had to fully understand the positive and negative effects of positive pressure ventilation.  First, at which time is it appropriate to apply positive pressure ventilation as opposed to standard ventilation?  Should positive pressure ventilation be used on very large structures such as hospitals or malls?  It could be assumed that the flowing of air in such a large structure could enable extreme fire extension that could go undetected thus spreading embers making the situation worse.  Lastly, what is the appropriate size of fans to be used for positive pressure ventilation, and does the NFPA have a standard that address the minimum requirements of such fans?  A scientific approach seems to be the best method to find the resolution to these questions.

Reference:

Kerber, S., & Walton, W. D. (2005). Effect of positive pressure ventilation on a room fire. doi:10.6028/nist.ir.7213