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Good to know


Welcome to a tour of a house fire

Fire can destroy your house and all of your possessions in minutes, and it can reduce an entire forest to a pile of ash and charred wood. It's a terrifying weapon, with nearly unlimited destructive power that kills more people every year than any other force of nature.
In as little as 30 seconds a small flame at home can become a major fire and threaten the lives of the people inside. And even if individuals are spared, fire can cost plenty money to rebuild your possessions engulfed in flames.
Thirty years ago, you had on average about 14 to 17 minutes to escape a house but nowadays fires have become more dangerous and devastating because of the flammability of the materials in the house. Occupants have roughly 2 to 3 minutes to get out… According to various tests home with mostly synthetic-based furnishings can be entirely engulfed in less than 4 minutes.
So what happens in those first few minutes of a fire that allows it to go from manageable to out-of-control? If You’d like to learn how you can protect your home, your loved ones, and your own life read on…

1st stage - Ignition
For almost half of all home fires starts on the stovetop since cooking fires account A few seconds is all it takes for a pot or pan to boil over the rim, spilling flammable oil-laden contents directly onto the cooking flame or red hot electric burner. In a few hundredths of a second grease or oils ignite into flames. The flashpoint of many common cooking oils is around 315°C, but when gas or electric burners are placed on high, temperatures it can approach 540°C.
First 30 Seconds
Within seconds of a flame-up, fire easily spreads. Spattered grease or oil residue on a dirty stovetop will ignite, causing flames to travel across the range. Oil residue on cooking utensils also ignite, and other combustibles like paper towels, paper or cardboard packaging, and dry dish towels nearby will begin to smolder or burn. Smokes are deadly combination of hot gases (carbon dioxide, carbon monoxide, water vapor, hydrogen sulfide and unburned hydrocarbons) rises up off the flames with the heated air. Extinguishing the fire at this point is crucial! Do not attempt to move the pot or pan. You risk burning yourself and spreading the fire around the room. And never throw water on a cooking fire; that will just spread the greasy flames. Instead, cover the pan with a lid or inflammable sheet to deprive the fire of oxygen and put out the flames.

30 Seconds to 1 minute
As the fire grows higher and hotter, more flammable objects and furnishings will ignite from spreading flames, including wooden cabinets and countertops, wallpaper, hanging baskets, and curtains. With the fire moving beyond the stovetop and other areas beginning to burn, a denser plume of hot air and smoke rises and spreads across the ceiling. If you're still in the room, this hot, smoky air can instantly burn the inside of your breathing passages, fire generate highly poisonous gases, including hydrogen cyanide (created when insulation, carpets, clothing, and plastics burn). Just two or three breaths of it and you could pass out.

1 minute to 2 minutes
As the flames intensify, the smoke and hot air rising off the fire are more than 90°C. Heat from the fire radiates to other parts of the kitchen, heating up tables, chairs, shelves, and cookbooks. The hot cloud of smoke thickens and deepens below the ceiling. While cyanide and carbon monoxide levels steadily increase, survival time is cut to less than one minute. Carbon monoxide poisoning causes more fire related deaths than any other toxic product of combustion. When the smoky layer reaches a doorway, an open window or a vent, it quickly streams out of the room. Then poisonous smoke and heated air travels through hallways and up to the second floor.

2 minutes to 3 minutes
The fire consumes kitchen cabinets, wood countertops and shelves stocked with plastic storage containers and dry goods like cardboard boxes of cereal, crackers, and cookies. More and more heat is generated. The temperature in the upper layer of hot gases rises to 200°C it is hot enough to kill people. Compounding the heat is a very dense smoke cloud hovering just a half meter above the floor. It may also include more toxic components like arsenic (used as a wood preservative) and lead (from old paint), as well as irritants like ammonia, oxides of nitrogen, hydrogen chloride and isocyanates. The fire can now spread by two paths: direct flame contact or by auto-ignition, the temperature at which objects will spontaneously burst into flames without being touched by flames. The auto-ignition temperatures of hard and soft wood used in furnishings and home construction fall between 315°C to 390°C.

3 minutes to 4 minutes: Flashover!
In just 3 and a half minutes, the heat from a room fire can reach almost 600°C. As this happens, flashover occurs. Everything in the room bursts into flames… Dining table, wood and upholstered chairs, cookbooks, curtains and wall decorations. The oxygen in the room is virtually sucked out glass windows are shattering. Balls of fire and flames shoot out windows and doorways. Rooms are filled with thick, hot, noxious smoke. When you have flashover in a room, temperatures can reach up to 760°C now, all of the other rooms in the house are severely at risk.
Flames poor through the doorway into the neighboring living room, setting the carpet and upholstered furniture on fire. Synthetics like polyurethane and polyester foam in sofas, pillows and carpets release tremendous amounts of heat. The temperature above the sofa quickly rises to 260°C. Back in the kitchen, the blaze has penetrated the wall and ceiling and flames travel quickly through structural shafts in interior walls and between floors. Fire spreads to other floors.

House Fire: 4 to 5 minutes
Flames are now visible from the street: they travel outside the house through the door and broken windows and into open second story windows. Rescuing anyone still trapped on the second floor now may be impossible. As the blaze in the living room intensifies, the room flashes over. The type of construction materials used to build your home will influence the severity of damage. Synthetics like polyurethane, polystyrene, and PVC used in glues, insulation, and plumbing will auto-ignite at temps between 450°C and 580°C. At 540°C steel plates used in engineered roof trusses will start to buckle and they lose almost half of their load-carrying capacity. Newer homes built with engineered wood can experience floor collapse in as little as 6 minutes. Roof collapse can follow very soon after in an out-of-control blaze.
Firefighter Action
If flames are visible from the outside when firefighters arrive, they immediately go into an aggressive attack strategy trying to ascertain if they can still save lives. Next they direct water to extinguish the blaze at the heart of the fire. Water simultaneously cools the burning debris (lower temps mean fewer flammable gases being generated) and can limit oxygen's ability to fuel the fire. Firefighters, on average, use nearly 3,000 gallons of water on a house fire. Firefighters may also vent off hot smoke and gases either by breaking open upstairs windows or cutting a hole in the roof. They may also use dry chemicals to retard fire spread and extinguish flames.
The Aftermath
Extensive property damage extends to the entire house. Even in rooms untouched by flames, high heat has softened window glass, melted plastic, caused paint to blister and charred wood. Most appliances are a combination of metal and plastic, so even if they are still standing, chances are they are ruined, with innards melted and destroyed beyond repair. And after flames are extinguished danger still lurks: many of the burned or melted plastics and synthetic materials in your home will continue to off-gas toxins. It is unsafe for anyone to enter the structure. Likewise, unseen weaknesses in the structure may still cause collapse.
Whether or not your house will be livable after a major fire will depend on many factors, and you will need to obtain permission from the Fire department to re-enter your home. Burned or unstable wood in the structure need to be replaced. After a major fire walls are left dehydrated and crumbling and also must be replaced. Given the high temperatures of large fires, most if not all of the home furnishings may be unusable. Expect weeks, if not months, to do cleanup and repair before you can bring your family home.

After reading this do you still think you don’t need a fire extinguishing spray or a fire extinguisher at your house?

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