Sunday, April 30, 2017

Why You Can’t Believe Everything You Read on the Internet

This morning’s foray around the Internet uncovered this handy little survival hack:

“If you're caught in a burning building, remember to stay low.” 

(Photo by R. Widmar - Copyright 2016-2017)
Good advice. Firefighters preparing to enter a burning building will crouch in the doorway to stay below heat and smoke. They often crawl on hands and knees to advance the hoseline into the structure and conduct searches for victims. They also teach kids to “crawl low in smoke” during fire safety presentations.

However, the following explanation that accompanied the survival tip is hit-and-miss in the facts department:

“Most fatalities in a house fire start with smoke inhalation. The fire is rapidly consuming all the oxygen at the top of the room. All the breathable air will be collected near the floor. Crawl on your belly to make your escape.”

Let’s break down these assertions one by one.

1. Smoke inhalation. Statistics show that more fire deaths occur from smoke inhalation, or a combination of smoke inhalation and burns, than from burns alone. (See Fatal Effects of Fire, National Fire Protection Association, 2011).

Smoke is a byproduct of combustion (the burning process). It is composed of particles and toxic gases such as carbon monoxide, hydrogen cyanide, and phosgene – all nasty stuff that’s not conducive to survival.

A person or animal doesn’t have to be in the same room as a fire to fall victim to the toxins it produces. Out of 85 fatalities in the 1980 MGM Grand Hotel fire in Las Vegas, 80 died from carbon monoxide circulated by the building’s ventilation system. The majority of these victims were found on upper floors of the hotel, well away from the casino where the fire originated. (“Lessons from the Past: MGM Grand Fire,” Firehouse.com, Nov. 18, 2010)

The superheated air in a fire can also be deadly. If it’s hot enough, one breath can fatally sear the lungs. Damage to the respiratory system can occur at temperatures of just 302 degrees Fahrenheit (150 degrees Celsius) or above. (Demling, R. H. (2008). Smoke Inhalation Lung Injury: An Update. Eplasty, 8, e27.)

2. Oxygen. Fire consumes all oxygen in a space, not just the oxygen “at the top of the room.”

3. Good air near the floor. Any breathable air will, indeed, be at floor level, but not because of oxygen depletion. Heat rises, so cooler air is found lower in the space. Smoke and other toxins also rise to ceiling level, either carried by heat or because some components are lighter than air. Smoke and heat will accumulate at the ceiling and then bank down to the floor.

A video created by the New Zealand Fire Service shows the progression of an “average” room and contents fire. At about two minutes and thirty seconds into the fire, the room temperature measured 1,491 degrees Fahrenheit at the ceiling and 282 degrees at the floor. (Check out the “virtual reality” fire experience at http://www.escapemyhouse.co.nz/.)

4. Crawl low to get out. Crawling low will help a person stay out of the worst of smoke, toxins, and superheated air when trying to escape a burning building.

While the basic advice to hit the deck if you are caught in a fire is sound, the reasoning given in this article isn’t quite accurate. Once again, it all comes down to doing a little fact-checking. Thanks to Google, it took me a lot longer to write this post than it did to find sources to back it up. “I don't have time for research!” is no excuse.

A great resource for writers of all kinds is the National Fire Protection Association (NFPA). Here’s the link to “A Reporter’s Guide to Fire and the NFPA”: http://www.nfpa.org/news-and-research/news-and-media/press-room/reporters-guide-to-fire-and-nfpa

Research. It’s a good thing.

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