He was reborn and became a firefighter again?

Chapter 462 Everything starts from the smoke curtain

"A comrade died as a result."

This sentence was shocking enough and won Fang Huai the silence of the religious officials and the solemnity of everyone.

Therefore, no one interrupted, and Fang Huai's voice continued.

"In modern building fires, the buildings are taller and more compact, and there are fewer bungalows with ventilation on all sides. Many buildings are not open around and have few ventilation doors and windows to the outside. Most of them are fire scenes with restricted ventilation, and the building materials and decoration materials contain The burning energy is far greater than before.

From the perspective of this development, it is time for our previous fire-fighting methods to change.

How to control the inflow of oxygen and control the air flow to change combustion conditions has become an increasingly important issue. "

As Fang Huai said, the scene of Xiao Hei's sacrifice kept flashing in his mind.

A small building with three floors and a mezzanine has a large interior space, but there are partitions and a total of three windows, which have not been fully opened.

Typical fire scene with restricted ventilation.

Thinking about it now, if the door is closed and the conditions for oxygen inflow are reduced, the fire will definitely burn smaller and smaller. Although the people inside will be in danger, a short period of hypoxia is not enough to cause death.

At least not more dangerous than a rapid rise in temperature.

But what were everyone doing that day?

When he arrived, the door was wide open, Xiao Hei was attacking from inside, and Hao Chengbin and Zhao Jincheng were standing at the door to control the temperature, with water guns firing.

Maintaining a cooling doorway for internal attackers is currently known as "gating."

No one thought it was wrong at the time, because everyone was taught that water cannons were used to cool people down and create safe passages.

But everyone, including Fang Huai, ignored why a fire with limited ventilation and obviously insufficient oxygen could burn more and more intensely without any signs of weakening.

It is precisely because of the open door and the two multi-functional water guns that they are constantly firing wildly at the big flowers, sending air in through water pressure!

They felt that it was leaving a door for Zhou Yong to escape, and they became the king of hell who wanted his life.

“In addition, in the past understanding, we thought that internal attack means breaking the door, and ventilation means opening the window.

In fact, any number of openings in a fire building structure will increase the heat release rate. Doors are also vents. The existence of a vent will change the path of smoke.

Especially when air with a certain pressure enters, the flow speed of the air will suddenly increase more than ten times!

The smoke surges out towards the door, and the firefighters enter through the door. What kind of high temperature and poisonous gas environment will the firefighters be in? How many degrees of baking will the combustible materials along the entire path experience?

Therefore, when ventilating and exhausting smoke, we must consider the strength of the first response force and cooperate with fire extinguishing instructions. Once ventilation is carried out without authorization, the fire will soon get out of control and people will be put in danger.

The door must be controllable. It needs to be opened briefly when entering and exiting, and then closed immediately. When smoke needs to be exhausted, only by opening the window to exhaust smoke in one direction can a stable one-way ventilation path be created. Otherwise, smoke cannot be controlled, and similarly, fire cannot be controlled.

This is true gated knowledge.

It's not a simple gate control, but a control of high-temperature flue gas and oxygen! "

Fang Huai said, almost wanting to slap himself twice.

Everyone said that after Zhou Yong entered, the cover team continued to spray water for cover, and the fire started to become fierce again, as if it was coming towards him.

This is probably because air is forced into the fire through the door again, causing internal pressure and causing the smoke to become disordered again.

In fact, I didn't have to fight hard to get in that day. I just had to get to the scene and close the door during Zhou Yong's first internal attack, leaving only the door crack where the water gun entered, and then cool down the entire second floor floor. Although the water vapor might briefly burn Zhou Yong. Brave, but with reduced oxygen and continued cooling, the fire will definitely develop in the other direction!

With this approach, when Zhou Yong enters the fire scene for the second time, the survival situation inside will have undergone a qualitative change. Maybe it will no longer be dangerous. Maybe, he does not need to retreat in a hurry at all, and can completely wait for his comrades to come to save him.

This obvious mistake caused by lack of knowledge made Fang Huai regretful.

Zhou Yong was very brave, but he did not die from bravery, but from ignorance.

The ignorance of comrades.

But comrades don't want to be ignorant, they lack correct knowledge and learning methods.

What Fang Huai said today was intended to be heard by the 46 commanders present, and even more so, by the commanders in the entire school.

The flow path of smoke has not yet been formulated in detail in any corner of the world. The religious officials naturally have no way to refute and can only be listeners, but the future commanders next to them are obviously more interested.

A curious student broke the silence.

"Then you mean you can't shoot flowers at the door?"

Fang Huai came to his senses after hearing the question and said:

"It's not that you can't shoot, it's that you can't use too much pressure, and you sweep the goal. The water pressure is high, the shooting area is wide, and you sweep the door. Is it pushing the air inside quickly?"

"But what we learn as recruits is to use two guns when entering the fire scene. The front one is blooming, and the rear one is direct current. The bloom covers the attack, prevents flame impact, and direct current ignites the fire source. It is like a hundred-meter ladder attack drill. After so long, It’s also very useful. If we don’t allow shooting at the door in the future, who will cover the internal attack?”

Everyone's thirst for knowledge brought a smile back to Fang Huai's face:

"When covering, you should use the door control method to tentatively enter. After the water gun enters the door and shoots water to cool down, you can go inside to operate. The door control method and the water injection method for transitional attacks should be based on the specific situation, and the religious instructor should be able to explain it.

All I can say is that with an unobstructed entrance, the nozzle should be as close to the inside of the fire scene as possible, and the water should be continuously adjusted at an angle to the ceiling. This is a method that can limit the entrainment of air by the jet and quickly cool down.

Moreover, the previous pattern of a group of guns covering and a group of guns attacking is not immutable. As long as a multi-functional water gun is designed that can spray flowers and spray simultaneously, it can bloom and spray directly. You can also set the nozzle to bloom on the edge and spray directly in the middle. , you can cover your own attack and enhance your mobility. "

"Well…"

It’s a great idea to add a DC belt to the multifunctional water gun.

If there is one more gun like this, if it is easy to use and has stable firing pressure, it will undoubtedly be good news for the under-strength squadron. Not to mention whether it will save people, whether it will be more flexible, and there will be one less cover gun to deal with a battle. After the fire, the hose can be saved by several dishes, right?

The discussion started to get louder and the thinking gradually became more active. Before the religious officials could control the situation, someone asked another question.

"If the door needs to be opened or closed, do we need a person to assist in opening and closing the door? We don't have enough manpower to begin with, so we have to add a security officer to close the door? And if the door is closed, what can we do if we can't see the inside?"

"You don't have to add people." Fang Huai shook his head and said:

"In Europe, there is a kind of smoke curtain, which is mounted on the door frame with a wide top pole. It is easy to hang and is fire-resistant. As long as it is hung, there is no need to repeat the operation of opening and closing the door.

After people pass by, the curtains will naturally hang down, and such blocking can give people the greatest sense of security and will not affect entry and exit.