If it 'was' ethanol, this fire-fighters article about ethanol fires (and explosions) make it clear the rain falling made it more explosive, not less, and that ethanol fires, though they burn clean and are heavier-than-air and so fall out of the air quickly, also
burn invisibly (I didn't know that) so I would think that would make it even more dangerous for fire-fighters and anyone around when it blew (if that's what it was):
Is Pure Ethanol Flammable?
Yes, pure ethanol is highly flammable with a flashpoint of just 12.7 degrees Celsius or 54.86 degrees Fahrenheit. (
According to OSHA.)
This means that pure ethanol will catch fire easily at room temperature and needs to be stored carefully away from naked flames or sources of sparks.
However, this doesn’t mean you need to panic about the alcohol you keep at home.
As you add water to ethanol, the flashpoint increases, and the vast majority of spirits (excluding those of the highest proof) and almost all wines and beers, have flashpoints above room temperature, though not so much higher that it would be a good idea to put them in a fire or near an open flame.
The good news is that ethanol is not likely to spontaneously combust and as it has an auto-ignition temperature of 793 degrees Fahrenheit (422.78 degrees Celsius), that is substantially hotter than found in most situations in real life.
Also read: Is Methanol Flammable?
Is It Explosive?
Ethanol is flammable and can also be explosive.
It weighs more than air, so it drops out of the air fairly quickly, but if it is aerosolized then as little as 3.3% concentration in air can be easily ignited and then explode.
There have been, quite literally, dozens of ethanol explosions at ethanol manufacturing plants around the United States.
For example, on the 24th of April
2009, there was an ethanol tank explosion in Bartow, Florida that saw flames shooting up to 40 feet in the air!
And a distillery explosion in Atchison, Kansas in September 2002, saw an entire plant blown up with debris thrown across the Main Street and which rocked many nearby buildings.
Can It Be Used to Start a Fire?
Ethanol, to some extent, makes an excellent fire starter, given its highly flammable nature it can be lit using heat, flame, or even just a spark and if poured on dry wood, for example, it will burn more easily than gasoline would.
As with all liquid fire starters, the liquid should not be added to a naked flame, or the flame may be drawn inside the container and cause an explosion.
A very sobering statistic, (excuse the pun), is that 100,000 people a year are admitted to hospitals in the United States and that nearly 50% of burn victims have been exposed to ethanol (including drinking it) beforehand.
Someone who has been consuming ethanol is 6 times more likely to die of burn injuries than someone who has not!
Do These Fires Smell?
Ethanol fires smell rather like vodka, there’s a distinct alcohol scent, but it’s not very strong and if the smell becomes strong, it means that the ethanol isn’t burning properly and that there’s an obstruction around the flame.
Is Burning Ethanol Dangerous?
Fire is always dangerous, and an ethanol flame is hot enough to harm, however, assuming you are burning ethanol in an appropriate vessel then it is not particularly dangerous to burn ethanol.
This is because it is a clean-burning fuel.
The formula of ethanol is C2H6O and when it burns in air, the components react with oxygen to form water (H2O) and carbon dioxide (CO2) and assuming that there is adequate ventilation, neither of these substances poses any risk to human health.
Does Water Put Out Ethanol Fires?
Water is not a good choice for trying to extinguish an ethanol fire and it is far more likely to spread it around than it is to extinguish the fire.
A small ethanol fire is best extinguished by cutting off the oxygen supply with a fire blanket or similar.
And if an extinguisher is needed, a foam extinguisher is ideal for smothering the blaze without spreading the burning ethanol around.
This is a big issue for fire departments that are involved with putting out ethanol blazes on highways and in industry as the foam used in these cases needs to be specially formulated with long hydrocarbon chains so that they can properly coat the flames without plunging into the burning liquid.
Is Ethanol Fire Invisible?
Yes, ethanol fires are invisible, and this makes them particularly dangerous as they may go unnoticed for several minutes until they spread to something which burns with a more visible flame.
Even on an industrial scale, ethanol flames can be invisible, and this presents a huge challenge for firefighters called to incidents at distilleries because they need to be certain that the flames have been fully extinguished throughout the site.
Are These Fires Good for Home Heating?
In many respects using an ethanol (or technically speaking in industry jargon – bioethanol) fire at home is an excellent idea.
Firstly, because it’s clean-burning you won’t need to install a chimney or a flue and you can rely on ordinary ventilation to clear out any fumes.
Secondly, “clean” burning is a literal thing, and you’re not creating any pollution with a bioethanol fire though, it’s not a perfectly green solution as carbon dioxide is a greenhouse gas.
However, given that all burning processes for generating heat involve producing carbon dioxide, this isn’t as big a downside as it could be.
Also read: Is Kerosene Flammable?
Do Bioethanol Fires Need Ventilation?
As we’ve already noted, bioethanol fires should not need any special ventilation.
However, if they are installed in a very small room with no windows or airflow, they might cause carbon dioxide build-up which could be problematic in long periods of operation.
In this instance, improving local ventilation would be a good idea.
What Happens If You Breathe In Ethanol?
You’re not too likely to inhale ethanol most of the time because ethanol is heavier than air.
However, it is possible to aerosolize ethanol and if you were to breathe in an ethanol mist, it might cause irritation to your nose and throat and even potentially make you choke or cough.
If you were to breathe in a lot of ethanol, you would feel drunk (mood changes, slurred speech, delayed reactions, etc.) and in very extreme cases, it could lead to alcohol poisoning and death.
We couldn’t find a single incidence of death by alcohol inhalation though, so if it happens, it is a real rarity.
firefighterinsider.com
