"Ahem, ahem!" Chen Xin was choked up.

Today is the third day that Chen Xin has entered the shelter, and after two days of adaptation and adjustment, Chen Xin feels that he has also adapted to the life of the shelter.

It's just that I don't know why today, the entire shelter is filled with the smell of choking smoke, which makes Chen Xin wake up directly from his sleep.

While coughing and covering his mouth and nose, Chen Xin got up from the bed and turned on the light in the room.

He shivered and got dressed, but he still felt dizzy, and even his breathing was a little unsmooth.

Chen Xin knew that it was not because he hadn't woken up yet, but because there were harmful gases in the choking smell of smoke in the air, and he inhaled a lot of smoke in his sleep, which affected his breathing.

If he hadn't been woken up by choking and continued to sleep like this, it was very likely that he would have died of hypoxia or harmful gas poisoning in his sleep.

Chen Xin, who reacted, hurriedly took out a gas mask and an oxygen cylinder from the cabinet on the side, and after inhaling a few breaths of oxygen for himself, he put the gas mask on.

After taking a few breaths of oxygen, Chen Xin finally eased up, and only then did he have the strength to think about what was going on.

There should have been no fire in the shelter, as he had not used any open flames at all, and even the induction cooker used to boil water for the past two days.

But at this moment, Chen Xin didn't think much about it, ran to the garage and picked up the small fire extinguisher in the trunk of the car, and then he checked the various places in the shelter.

However, what made Chen Xin very strange was that the shelter was not on fire, and there was no place for smoke.

Where does the choking smell of smoke in the air come from? These choking gases obviously smell after something burns, and if nothing burns up, Chen Xin absolutely doesn't believe it.

However, when Chen Xin started to check again, he finally found that the smoke came in from the vent of the shelter, and the smell of smoke entered the shelter from the outside.

This discovery made Chen Xin react, this is a fire outside!

After two days, did the fire caused by the meteorite impact finally reach here?

But this discovery made Chen Xin feel extremely helpless, because even if he knew the reason, he couldn't solve the problem.

It was a fire that spread to the whole world, and most of the vegetation would be ignited, although Chen Xin did not go out, he believed that the mountain where his refuge was located should have been burned, otherwise he would not have let his refuge have such a strong smell of smoke.

It is important to know that the ventilation system of the shelter is specially designed to filter smoke and toxic and harmful gases under normal circumstances.

But now the situation ...... It is clear that the smoke concentration from the outside has exceeded the limits of the ventilation system's filtration and tolerance.

Chen Xindun felt helpless and desperate, was he going to be smoked to death like this?

Although he prepared a gas mask and an oxygen cylinder, there was a limit to how long these things could be used.

In this environment where the smoke is gradually thickening, even if the quality of the gas mask Chen Xin bought is good enough, it can only last for a few hours at most, and the filter element on it needs to be replaced to ensure the filtration effect, while the oxygen cylinder can only be used for two hours.

Although the wildfires outside do not last long according to Chen Xin's estimation and will be extinguished by the drop in temperature caused by the sky being obscured by dust clouds, they will still last for several days or even more than a week.

Originally, Chen Xin thought that his shelter ventilation system was enough to ensure his survival for such a long time, but now reality gave him a merciless slap in the face.

If Chen Xin couldn't come up with a solution, after the gas mask and oxygen cylinder were ineffective, he would probably be smoked to death in this shelter like those who were smoked to death in the fire.

Get out? This is obviously impossible.

The smoke has smoked into the shelter, but it is conceivable that the outside has been surrounded by mountain fires, even if Chen Xin opens the door of the shelter and runs out, it will only change from bacon to roast duck in the oven.

And even if he could get out, where would he go?

This fire is not burning his mountain, but a super fire all over the world.

At this moment, more than 90% of the vegetation of the entire Blue Star has been ignited by the heat released by the meteorite impact, and the surface of the Blue Star is full of flames burning, and there is no place to escape.

There may be no flames at sea, but how can Chen Xin run from the inland to the coast?

Now that all the transportation systems have been suspended due to the impact of the meteorite, the state may still have secret routes, but how can this kind of thing be open to Chen Xin, an ordinary person?

And to be able to use this kind of secret line, Chen Xin still runs a hammer and stays in the secret bunker of the state.

As for official refuge, that's really an option.

It's just that there is a core issue here, that is, how can Chen Xin let the official shelter that has been closed open for him in such a situation of fire.

You must know that even Chen Xin's own shelter door is a 12-centimeter-thick solid metal explosion-proof door, let alone knocking on it with your hands, you just use a hammer to smash it outside, and you may not be able to hear it inside, not to mention that for safety reasons, Chen Xin also installed two doors.

One can imagine what the doors of the official shelter must have been.

So the option of escaping was not considered by Chen Xin from the beginning.

But if you don't run away, what can you do to survive?

The ventilation system has now reached its limit, and unless you change to a new and stronger ventilation system, you will end up being smoked to death in this shelter that you have built!

Wait a minute! Chen Xin suddenly had a stirring and thought of a key point that he had overlooked.

He could have changed to a stronger ventilation system, because he had the system!

Chen Xin, who thought of the system, hurriedly called out the system interface, and then looked at the ventilation duct of his own shelter.

Sure enough, the ventilation ducts in the line of sight lit up, and an upgrade plan was given.

"Natural Ventilation System"

"Upgrade plan 1: upgrade the filter material, improve the air filtration level, increase the forced mechanical ventilation function, and upgrade the required survival point 100"

"Upgrade plan 2: upgrade the pipe material, improve the insulation level, increase the temperature regulation function, and upgrade the required survival point 100"

Chen Xin didn't think about it, so he directly chose the first upgrade plan.

As he confirmed, the same grid of light appeared in the implementation as it had been when the system was first activated, but this time only on the ventilation ducts.

Soon, the brilliance dissipated, and the ventilation ducts of Chen Xin's shelter had been renovated and upgraded.