A: Hey there! Have you heard the news about that explosion in Tokyo?

B: Nope, I haven't. What happened?

A: It was this morning, at a housing construction site in Edogawa Ward. There was an explosion from a construction vehicle that was parked on a parking lot, and it damaged nearly 40 buildings around it!

B: Whoa, that sounds serious! Was anyone hurt?

A: Ten people got injured, but thankfully their injuries were minor. They complained of throat and ear pain.

B: I see... So what caused the explosion?

A: The police think it was a cylinder filled with highly flammable acetylene gas that was buried about 60 centimeters deep, and they suspect it got damaged during construction work.

B: Oh, I remember learning about acetylene gas in school. It burns really hot, right?

A: Exactly! Acetylene gas is used to weld or cut metals at temperatures over 3,000 degrees Celsius. And there are many of these cylinders found each year in Tokyo alone!

B: That's a bit scary... Are they safe if handled properly?

A: According to Toya Akihiro, an official from an association that handles high-pressure gas containers, they are generally safe as long as they're disposed of correctly in accordance with the law on high-pressure gas safety.

B: So if something like this happens again, it might be because the cylinder was improperly discarded?

A: That's what Toya thinks too. He says construction companies or others may abandon these cylinders when they're no longer needed or because disposal is too much trouble. But he assured that there's a low risk of buried acetylene gas cylinders exploding unless they're subject to extraordinary conditions.

B: I'm glad to hear it's not a common occurrence then! Thanks for sharing, buddy!

A: Of course! It's always good to stay informed. Take care!
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Police in Tokyo are investigating an explosion in a residential area that injured 10 people and damaged nearly 40 buildings.



The blast occurred on Tuesday morning at a housing construction site in Edogawa Ward. A construction vehicle was badly burned, and 38 homes and stores incurred damage to walls and windows.



Tokyo police say 10 people, including construction workers and residents, complained of throat and ear pain, but their injuries were minor.



Police and firefighters suspect a buried cylinder containing highly flammable acetylene gas was damaged, and that leaked gas was ignited.



The site is said to have been a parking lot. Workers were trying to drive piles into the ground there to build a home.



The cylinder was reportedly buried at a depth of about 60 centimeters.



Toya Akihiro, an official from an association of businesses that handle high-pressure gas containers, says acetylene gas burns at temperatures over 3,000 degrees Celsius, and is used to weld or cut metals.



He says several buried acetylene gas cylinders are found in any given year in Tokyo Prefecture alone, and his group receives inquiries about disposal from construction companies and others.



Gas cylinders must be properly disposed of in accordance with a law on high-pressure gas safety.



Toya said whoever uses such cylinders should take them away or return them if they are rented.



He added that although he does not know why the cylinder at the Edogawa site was left, it may be assumed that a firm abandoned it there because it was no longer needed, or its disposal was too troublesome.



Toya offered assurance that there is a low risk of buried acetylene gas cylinders exploding unless they are subject to extraordinary conditions, such as a huge shock.



He said his group has never experienced a blast during a recovery or disposal process, or found cylinders more likely to explode because they had gotten old.