"Under the table?" Su Ping sighed: "No, it can cause this level of fire and explosion, and the average indoor gas concentration should reach more than 1% at the time of fire...... Don't know, gas is a mixture of gases, so let's look at all the gases it contains as a whole for easy calculation.

The area of that conference room is not small, twenty-eight square meters, three meters high, close to ninety cubic meters, 1% concentration, almost one cubic meter.

Not to mention, you have to consider that the windows have been smashed, and there must be a lot of gas spilled outside. It seems that the gas canister is definitely not that small, even if there are multiple canisters.

If it is a portable small oxygen cylinder, it can still be hung under the table, but that kind of small oxygen cylinder can't release much gas even if it is plastered under the table, and the gas tank used by the murderer must be much larger than that kind of small bottle, and it can't be pasted.

So it's unlikely to be under the table, it must be hidden somewhere else. ”

Fang Chang was stunned for two seconds, hesitated for a while, then shook his head and said, "Then I can't figure out where they can hide the gas canister." ”

When Qi Yuan heard this, he couldn't help but scratch his head and asked, "Team Su, is there any point in guessing where they hid the gas canister?" When the brother from the fire department finishes surveying the scene, he should tell us where the fire started, so ......"

"In the case of a fire caused by a flammable gas, the ignition point is not necessarily the gas 'leak' point." Su Ping glanced at him and said: "For example, if there is an indoor gas leak, someone plugs in and unplugs at this time, and an electric spark is formed at this moment and then detonates the gas, then the ignition point is the plug, not the gas canister."

On the other hand, the gas is so spilling out that it doesn't take a few seconds after the fire to ignite the whole room, and it is not easy to determine the ignition point. ”

Speaking of this, Su Ping sighed twice, lowered his voice and said, "Besides...... The county has limited funds, and it is difficult to train and hire experts, so unlike the fire brigade in the city, it can conduct quite professional surveys of the fire scene in addition to extinguishing fires.

I estimate that if the brigade can extinguish the fire and prevent it from rekindling, it will already be over, and we will have to come to investigate the scene. However, although we all know a little about the investigation of the fire scene, it is not professional.

So there is no way, it is difficult for us to conduct an effective survey of the fire scene where most of the clues have been destroyed by the flames, and the shock wave generated by a few explosions may also displace many things and become unrecognizable, so we can only rely on the method of logical reasoning to guess.

As for what you say, what's the use of guessing these...... You regard the fire as a homicide, do you think that the murderer's modus operandi in the murder is not an inconsequential matter? ”

Qi Yuan didn't seem to understand.

But Su Ping didn't explain anymore, but you and I were discussing something with Fang Chang and Su Ping, and Qi Yuan was listening on the side.

In the end, there was no definite outcome from the discussion.

After another fifteen minutes, Lao Wei, who had received Su Ping's notice earlier, finally arrived at the county bureau with the trace inspectors dispatched. As for Lao Wei himself, he still needs to continue to rely on those handicrafts to sort out the hidden clues one by one.

This matter is more critical, and he does not dare to hand it over to others. Su Ping didn't dare to let him hand it over to others, judging from this fire, this criminal gang was not only much more vicious than he had previously estimated at this moment, but also infiltrated them more than he imagined, and could even penetrate into the brigade to commit murder......

Of course, it is more likely that the guys behind the gang did something to protect themselves, and it has nothing to do with the gang. It's just that I have to guard against it, after all, this matter is too big and very critical.

As soon as they arrived, before they could chat with Su Ping, the instructor and captain of the fire squadron came to Su Ping, saluted, and told them that the fire had been completely extinguished, and the scene had been cooled down and a layer of flame retardant had been extinguished, and the risk had been removed, and they could enter the scene for investigation.

As for the investigation of the fire scene, such as the ignition point and the like, he didn't say it, and Su Ping tacitly didn't ask, knowing that this matter was beyond the scope of the squadron's ability.

"At the grassroots level, the degree of specialization is still not enough." Seeing the firefighters go to the side to rest, Su Ping sighed softly.

But there was no way, he couldn't solve it, and he couldn't solve it.

The specialization of the grassroots contingent involves too many aspects, and the most important thing is that neither money nor education can be missing, and neither economic construction nor education is in a hurry, and it is impossible to achieve results in a short period of time, so it can only rely on the current major policy to evolve slowly.

After packing up the thoughts in his heart, Su Ping led a group of people into the fire.

The firefighters didn't leave, although they had no problem packing tickets, but there was still a little bit of risk, stay a little longer, in case of a fire, they could put it out as soon as possible.

They squatted on the sidelines, smoked, rested, and applied some burn cream to each other's burned colleagues.

The three trace inspectors quickly got into work, and Su Ping couldn't help, so he could only look around.

But there was one thing they determined as soon as they entered the fire - the location of the gas canister.

It's really the location that Fang Chang first proposed, but thought it was unlikely, in the big cabinet of multimedia equipment.

At this moment, the cabinet has been directly deformed by the explosion, and it is almost impossible to see the original appearance. After analyzing it for a long time, the trace inspector speculated that a lot of the hardware in the multimedia equipment had been removed, and the vacated space was used to put gas canisters.

After careful analysis, it is estimated that there are a total of five gas canisters hidden inside, which are five kilograms.

The trace inspector looked at it a few more times, opened the notebook and took a look, took out his mobile phone and opened the calculator to calculate for a long time, writing and drawing in the notebook while calculating, and finally said: "This kind of 5-kilogram gas tank, as the name suggests, is allowed to fill up to 5 kilograms of liquefied gas in the tank."

The density of liquefied gas is about 580 kilograms per cubic meter, and if the gas is full, it is almost 8.6 liters. Liquefied coal gas is converted into gas gas, which expands by a volume of about 240 times, that is, a tank can release a maximum of about two cubic meters of gas.

There are a total of five gas canisters hidden in it, which means that the maximum amount of gas can be released is 10 cubic meters...... Of course, if the gas tank is not satisfied, or cutting corners or something, it is difficult to say. ”

Su Ping immediately asked, "Can you see how the valve of this gas tank is opened?" ”

"Huh?"

Fang Chang took over and explained: "We speculate that when we first came in, the valve of the gas tank was closed, and it was only opened by remote control after we came in. Can you see exactly what method was used? ”

"This ......," the trace examiner hesitated for a moment, then said, "I'll take another look." ”