Emergency Service Myths

Comment

Comment by Michael Bricault (ret) on May 7, 2010 at 2:15pm

-Mark, it is about time someone finally addressed the foolish myth of fog nozzles being used to "protect" firefighters. The best way to protect firefighters is two fold; put water right on the material that is burning and aggressive ventilation.
-The ventilation operations usually do not include roof venting as it is to time and manpower intensive and therefore never accomplished in a timely enough fashion as to be definitive and/or beneficial to the attack and search teams.

Comment by Mark J. Cotter on June 7, 2009 at 9:52pm

Ian,
Interesting where the discussion of Water Curtains has taken us. The way I understand it, the basic premise of your department's "Left for Life" myth is that a water spray from a combination nozzle opened to full fog will provide a barrier to the heat from a flashover. Unfortunately, water is a poor barrier to radiated heat, as discussed in my columns at some length, and would be no more effective indoors than outside. Further, a flashover by definition is the nearly simultaneous ignition of every surface in a compartment - over, around, and under any firefighters within - so, where would the nozzle be directed? Even using a wide stream pattern to "push back" a fire blowing down a corrider or out of a room has been proven to be a poor practice indoors due to the significant blow back and churning of the entrained air. The great protection fog nozzles provide a hose team approaching a fire outdoors is, unfortunately, not the same effect when they are used indoors.
Now, I am not necessarily a diehard fan of solid nozzles over combination - they both work fine when used correctly. Solid streams have an edge with handling in that they have a lower nozzle reaction (by being operated at 50 psi), though there are now low-pressure combination nozzles available. On the other hand, combination nozzles set on a wide pattern can move a lot of air and assist with ventilation, though this is also a big problem if they do so inappropriately (like, while aimed at a fire indoors). Solid and straight (combination nozzles set on the narrowest pattern) streams are equivalent in extinguishing effect. Bottom line, in my opinion, is that there is no advantage to a combination nozzle in protecting a team from flashover. Truly, there is probably NO defense once it occurs - everybody will likely be dead in a few seconds if they are not already headed for an exit - so prevention is the way to go: put out the fire before it flashes, or stay out of its way if you can't. Hope this helps you to keep your brother firefighters out of harm's way.
By the way, I have belonged to several volunteer fire companies in my career that had bars in the stations - one even had a beer dispenser in the apparatus bay. Fortunately, for most of the fire service, times have changed for the better, but I still like to shock some of the younger members with such stories.

Comment by Mark J. Cotter on April 15, 2009 at 12:32pm

Brad,
Good one, and the first I recall considering that comes from outside the emergency services community (we're usually our own worst critics). The best evidence against this comes from the ISO (Insurance Services Office) rating system that is utilized by many fire insurance companies in setting policy rates. The equipment, personnel, policy, and infrastructure (water supply, etc) requirements can be directly tied to the cost of obtaining insurance coverage, an amount fixed for several years at a time. Mulitply the savings (or loss) for all of the residences and businesses in your district creates a powerful high dollar figure. For EMS, calculating the response time for each area of the district, after allowing for unit activity, when coupled with the recommended 8-minute maximum (based on cardiac arrest requirements) provides an easy-to-convey argument for adequate units and staffing. One final tool in confronting this myth is to turn it back on the accuser by asking how much risk they wish to allow with their reductions in training, staffing, unit deployment or replacement, or services available? Describing a scenario that is possible for your jurisdiction (haz mat spill, wildfire conflagration, etc) and your current ability (or inability) to address it in a timely manner can be a powerful argument. Finally, we need to be good stewards of the monies we are charged with spending, but the "black h***" myth often rears its head to even fiscally prudent departments. Thanks for the input.
Mark