Baltimore Gas & Electric building explosion

[Eufalconimorph]

https://baltimore.cbslocal.com/2020...ured-21-rescued-partial-roof-collapse-latest/

Given the reports of burn injuries, that BGE states it was NOT a gas explosion, and that it was an explosion I'd guess steam. Safety systems should prevent that, so I'd say there's a failure involved somewhere, whether engineering or maintenance I can't say. The building seems to have handled things well, and directed the energy out the roof instead of shattering all the windows and dropping glass onto the sidewalk, so that part is an engineering success.

 

[SnTMan]

Quoting from the article, "The building’s gas service was not active due to the construction work...".

Hmmm, wonder where the steam could have come from? Electric boilers?

The problem with sloppy work is that the supply FAR EXCEEDS the demand

 

[davidbeach]

Central (district) steam?

I’ll see your silver lining and raise you two black clouds. - Protection Operations

 

[bimr]

The incident at BGE’s offices was related to construction, said Stephanie Anne Weaver, the company spokeswoman, in a statement. Work on the building’s “air handling and boiler system,” which is housed on the 16th floor, likely was the culprit, she said. She said the natural gas in the building was cut off due to the construction.

 

[SnTMan]

Yeah, you know how common air handler explosions are

District steam may make sense. I have no idea..

The problem with sloppy work is that the supply FAR EXCEEDS the demand

 

[miningman]

propane

 

[MJCronin]

Condensate water hammer in the ancient building or district steam system..

The "Buttahollei Brothers Mechanical Contractors" (of East Baltimore) recently announced to the media... "Never in our four years of business have we ever seen anything like this !!! ... Must be an act of God ... act of God "

Except, of course for the many, many competent Engineers and consultants who have seen this kind of carnage before ...

Wayne Kirsner has been here before ...

http://www.kirsner.org/pages/articlesAlt.html

My question..

Was there any kind of written startup procedure, stamped by a Professional Engineer developed for this steam system work ?

If not, why not ???




MJCronin
Sr. Process Engineer

 

[waross]

On a construction site, a welder had done some cutting above a scaffold.
It was tight quarters and he had to climb above the scaffold.
He finished cutting and dropped his torch onto the top of the scaffold.
He was going to start grinding.
To get into a better position, he took off his leather jacket and dropped it on top of his torch.
He started grinding.
His acetylene valve was leaking and acetylene was accumulating under his jacket.
Sparks from the grinding ignited the acetylene.
We were on the other side of a concrete block wall when we heard a very loud explosion.
The jacket was shredded.
I'll vote for the ignition of leaking acetylene or propane or other combustible gas.
Steam or condensate do not often start fires.
Bill
--------------------
"Why not the best?"
Jimmy Carter

 

[JStephen]

Since gas was cut off, it shouldn't be a gas explosion. But then again, there's nothing else that SHOULD be exploding up there, either, so obviously something exploded that shouldn't have. Meaning, it's just as likely a natural gas explosion due to thinking it was cut off and it really wasn't or something like that.

 

[bimr]

The incident is likely construction related and not from natural gas, and occurred while crews were working on the building's air handling and boiler system, a release from BGE said.

"Twelve of the contractors who were injured have been treated and released from the hospital. A number are still in the hospital receiving treatment," Koos said.

The building was mainly empty at the time because of the coronavirus pandemic and the holidays.

Could have been a propane space heater. May also have been acetylene or oxygen cylinders. Acetylene is particularly hazardous with a "Lower Explosive or Flammable Limit" of 2.5% (% by volume of air)

 

[FacEngrPE]

I would put my guess with a flammable gas explosion. I am not going to guess the source of the gas as all of the suggestions above are reasonable guesses.
A water hammer event is also reasonable but would be more likely to release energy in the basement. A possible scenario would be that the building riser between the basement and the roof fills with water, then someone opens a valve and suddenly drains the riser into the supply main. The cold water will create a sudden drop in pressure, which can then launch a water slug at ~ 5000 fpm. That becomes a very hard hitting hammer.

Another unusual scenario that is a plausible cause of the observed roof damage is an improperly handled acetylene cylinder.

If an acetylene cylinder is placed on it's side, it can become very dangerous to handle or use. Linde has published that as many as 1/3 of the available cylinders distributed at what they call the retail level are handled incorrectly. This clip is a bit basic, but it does present the most important point

https://youtu.be/lEVBoc4tLoI.

An improperly transported or stored acetylene cylinder could cause similar damage if it exploded.

Fred

 

[bimr]

Fred, agree with your comments.

Acetylene cylinders aren't supposed to be stored in confined spaces as the "Lower Explosive or Flammable Limit" is just 2.5% (% by volume of air). Where I worked, the unskilled staff kept cylinders in the back of a transit van and one of the vans exploded while being driven.

This image shows what happens when acetylene cylinders are housed in a enclosed van. The electric clock in the vehicle is enough to ignite the acetylene.

There a number of safety bulletins on this.

safety bulletin

 

[Eufalconimorph]

Yeah, acetylene cylinder explosions are definitely a possibility, especially now that the article mentions burn-related injuries. Any compressed gas cylinder exploding can be devastating, flammable gases even more so. Even non-flammable gas cylinders are dangerous, EG this incident where an argon cylinder explosion killed one and injured 6, and caused extensive damage to the internal structure of the building.

 

[MacGyverS2000]

Unfortunately, not signing up for a subscription to the Telegraph just to read an article...

Dan - Owner

http://www.Hi-TecDesigns.com

 

[Eufalconimorph]

Fire services, police and paramedics were called to the Mundells, an area near Welwyn Garden City, Hertfordshire, shortly after 3pm.

Six wounded men were taken to the Queen Elizabeth II Hospital in Howlands, Herts. where one remains in a critical condition and one is seriously injured.

Following a subsequent search of the building a body was discovered.

A Hertfordshire Police spokesman said: "I can now confirm that one man has tragically died as a result of the incident.

"His family has now been made aware and a trained officer is providing them with some support at this time."

It is believed the blast happened after an argon cylinder exploded inside a building still under construction.

Following the incident around 150 builders were evacuated from the site and all surrounding roads were closed.

Jon Smith, Group Commander of Hertfordshire Fire and Rescue, said that the explosion had caused extensive damage to the inside of the building.

He said: "A cylinder of gas depressurised, there was no actual fire, the gas is inert, which acted like a missile and set off the other cylinders.

"Each cylinder weighs about 50kg and is about 5ft tall, they've made a real mess of the inside of the building, they've taken down walls and floors."

The argon cylinders were being used as a fire suppressant in the building, which is being built by construction firm Laing O'Rourke.

He said that the external structure was intact but that 50% of the internal structure had been affected.

The Health and Safety Executive are aware of the incident and are monitoring the situation.

A spokesman said: "The operation at the scene has now reduced and the area is returning back to normality.

"This includes the local road network which is operating as normally as possible."

They have advised workers that they should be able to return to work.

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