Blue Flower

One more thing that needs to be understood by those who want to search safer and more efficiently is that the modern fires are more dangerous than those we fought 30 years ago. Without this understanding you are prone to either using obsolete and unsafe methods or failing to learn the new ones.

So in what ways exactly have the modern fires become more dangerous and why did that happen? The answer consists of two parts: synthetic fuel loads and lightweight construction. Let’s discuss them one by one.

First of all, 30 years ago when the house was on fire, it was mostly wood and other natural materials that were burning. From furniture to decorations to construction materials, natural materials were dominating the scene. Walk inside any modern premises – residential or commercial – and you will see a dramatically different picture. Appliances are made out of plastic, furniture is both made of and stuffed with synthetics, carpets and floors are synthetic, and even if something looks like wood, look closer – in most of the cases it will be some form of engineered wood held together by synthetic glue.

The problem with synthetics is that they burn faster, hotter and yield a black dense smoke and much more toxic products of combustion than wood.

Take ABS plastic as an example – it yields around 38 megajoules of thermal energy per kilogram of fuel burnt. Your good old wood yields between 9 and 18 megajoules per kilogram. You know what yields almost the same amount of energy as ABS plastic? That’s right, gasoline, with 43 megajoules. So when you fight a modern apartment fire, you should expect an equivalent of a burning barrel of gasoline, and not an equivalent of a couple of wooden logs like it was decades ago. A modern fire will spread faster and will deal more damage in the process.

Thick black smoke produced by burning synthetics dramatically reduces visibility and this makes the searches more dangerous. This is a reason why we can no longer rely on “c’mon, I will likely see something inside” and always train in zero visibility. Oh, and this black smoke is full of incompletely combusted fuel particles, so it will re-ignite together with the rest of the room and burn you to death. Wonder why flashovers and smoke explosions became such a big problem recently?

Finally, synthetics produce much wider array of toxic substances when burning. We all are familiar with the carbon monoxide, but it is not the only issue. Hydrogen cyanide came to be a problem only when synthetic materials became prevalent. And it is 35 times more toxic than carbon monoxide in the same concentration. Add to this all sorts of carcinogens that are produced too and you are facing chronic health issues in addition to the possibility of acute poisoning.

Now to the second reason why modern fires are more dangerous than ever – lightweight construction. Gone are the days of solid building materials, the construction industry has switched to trusses, engineered wood, glue and other synthetic materials. Both wooden and metal trusses fail under fire loading much quicker and without any advanced warning compared to good old solid beams. Both floors and roofs are no longer safe to be on during the fires, and especially roofs.

Trusses also form opportunities for voids that serve as excellent channels for spreading of both fire and products of combustion.

If you fail to recognize all these new dangers, if you are stuck with the ways that worked years ago, if you are searching inside randomly or with a hope to see something, if you are not breathing from SCBA while being anywhere in the burning building during the fire and 24 hours after it too, you are dramatically increasing your chances of getting killed in the modern fire.

Next: Fireground priorities