Massachusetts gas fires: Another technological tragedy • Hacker News Board

Re: Massachusetts gas fires: Another technological tragedy

#91

Post by wmoser » Sun, Oct 21, 2018, 1:06 PM UTC

pedrocr wrote: post #79

wmoser wrote: post #46

Earlier quoted context omitted.

Probably a giant radiator. Lots of equipment that is “air cooled” has an intermediary coolant that is actually cooled by air over a heat exchanger (radiator).

That's confusing. "Air cooled" usually means exactly that there is no "intermediary coolant". At the end of the day almost all equipment cools to the atmosphere after all. The difference between liquid cooled and air cooled cars/bikes is exactly that extra equipment of coolant lines and radiators versus just having airflow directly over the things you want to cool.

I wasn’t very clear, if the NaK is liquid it could flow through a radiator and could still be considered air cooled.

While there are some pure air cooled engines, lawn mowers, motor cycles, etc. A typical car engine is also considered air cooled since it gives off its heat to atmosphere even with assistance of a coolant radiator system.

Most marine engines, some power plants and some industrial equipment is considered liquid cooled since the coolant passes through a fluid to fluid heat exchanger and then that cooling water gets put back into the ocean/river. An example would be some ABB drives come in a LC liquid cooled or AC air cooled package. The motor drive lineups are the same with primary coolant going through all the drive bays the difference is at the end if they put an liquid to air or liquid to liquid heat exchanger.

Re: Massachusetts gas fires: Another technological tragedy

#92

Post by specialist » Sun, Oct 21, 2018, 1:09 PM UTC

edejong wrote: post #67

joe_the_user wrote: post #39

I had believed such a catastrophe was all but impossible. The natural gas industry has many troubles, including chronic leaks that release millions of tons of methane into the atmosphere, but I had thought that pressure regulation was a solved problem. Yeah, natural gas tech is old and over time has been worked into a multi-layer system that is close to "inherently safe". I remember years ago trying to light an old h…

I wish we could just separate technology and human factors like this. In reality, each system is designed to prevent neither technological malfunction nor miscommunication or errors in process. Unfortunately, programmers seem often to be isolated from this really complex part of engineering, so this interplay might not be appreciated properly.

Donald Norman's Design of Everyday Things helped cure my technophilia, maybe even turning me into a humanist. http://a.co/d/dSsOfxJ

Aha, looks like there's a new version (dated 2013).

Re: Massachusetts gas fires: Another technological tragedy

#93

Post by antidesitter » Sun, Oct 21, 2018, 1:47 PM UTC

anovikov wrote: post #70

acidburnNSA wrote: post #2

"All of these events feel like unnecessary disasters—if we were just a little smarter, we could have avoided them—but the fires in Lawrence are particularly tormenting in this respect. With an aircraft 35,000 feet over the ocean, you can’t simply press Pause when things don’t go right. Likewise a nuclear reactor has no safe-harbor state; even after you shut down the fission chain reaction, the core of the reactor gen…

Other kinds of consequences like cost of mitigation, value of lost property (and lost value of property what wasn't destroyed by itself - you can easily see thousands of homes near, but not in evacuation zone deprecating severely), costs of health checks for hundreds of thousands of people etc. - are worse in nuclear accidents.

> are worse in nuclear accidents

Do you have numbers for this comparison?

Re: Massachusetts gas fires: Another technological tragedy

#94

Post by phkahler » Sun, Oct 21, 2018, 2:03 PM UTC

jplayer01 wrote: post #87

chmod775 wrote: post #84

Earlier quoted context omitted.

To put that into perspective, about 120,000 people are displaced every day in the middle east because of a mess ultimately created in the pursuit of oil interests. That's one Fukoshima every day . Apparently the US felt that hundreds of thousands dead, millions displaced, and democratic governments overthrown was an acceptable price for slightly cheaper oil. I fully expect that calculation to come out the same when c…

Not sure why you were downvoted. You're entirely right. Oil is incredibly destructive for the environment and society, yet it's accepted because that's just how things are.

Our entire civilization runs on energy, mostly from coal and oil. Until recently it was not feasible to use alternatives. Change takes time.

Re: Massachusetts gas fires: Another technological tragedy

#95

Post by amluto » Sun, Oct 21, 2018, 2:17 PM UTC

I find it bizarre that it’s not required by code for a pressure regulation station to have a sensor in that station.

I also wonder if the utiliy’s connection between the sensor and controller is on the internet.

Re: Massachusetts gas fires: Another technological tragedy

#96

Post by donavanm » Sun, Oct 21, 2018, 2:46 PM UTC

hyperion2010 wrote: post #44

Oh man. My PhD work is focused on helping people communicate clearly about the measurements they are making and how to interpret them and where the pitfalls are in a research setting. Every time I read about something like this I wonder if I can use what I am working on to help people automatically detect when the assumptions of their measurement model could be violated. For example, if you can explicitly model the f…

If you havent yet you should check out Sidney Dekkers writing. He does a lot of work around human factors and perception in the area of safety & operations management.

Re: Massachusetts gas fires: Another technological tragedy

#97

Post by EamonnMR » Sun, Oct 21, 2018, 3:00 PM UTC

acidburnNSA wrote: post #2

"All of these events feel like unnecessary disasters—if we were just a little smarter, we could have avoided them—but the fires in Lawrence are particularly tormenting in this respect. With an aircraft 35,000 feet over the ocean, you can’t simply press Pause when things don’t go right. Likewise a nuclear reactor has no safe-harbor state; even after you shut down the fission chain reaction, the core of the reactor gen…

Regionally this was covered extensively with pictures of devastated houses and graphic detail about the fatality.

Re: Massachusetts gas fires: Another technological tragedy

#98

Post by Piskvorrr » Sun, Oct 21, 2018, 3:01 PM UTC

phkahler wrote: post #94

jplayer01 wrote: post #87

Earlier quoted context omitted.

Not sure why you were downvoted. You're entirely right. Oil is incredibly destructive for the environment and society, yet it's accepted because that's just how things are.

Our entire civilization runs on energy, mostly from coal and oil. Until recently it was not feasible to use alternatives. Change takes time.

Time which we might not have, especially given the political pushback.

Re: Massachusetts gas fires: Another technological tragedy

#99

Post by dsfyu404ed » Sun, Oct 21, 2018, 3:13 PM UTC

Properly installed residential gas piping should be able to handle triple digit pressures. Appliances should be able to handle double digit pressures because almost all appliances that can run on NG also can be equipped to run on propane which outputs at up to 30psi depending on the regulator. Manufacturers slap a safety factor on top because it's a consumer product and you don't want someone to blow up their house and sue you because they used the wrong regulator.

There's a reason some houses went bang and some houses didn't.

I know it's fashionable to blame the megacorp (and it sure looks like they have plenty of blame in this case) but there's plenty of blame to go around here. There's a reason some houses went bang and others didn't. I've worked residential construction in MA and plumbers as a group have a pretty bad reputation (well earned, at least based on my experience, you should see some of the corners these guys will cut). I would wager that the houses that went bang weren't the ones that had their gas pipes done by the apprentice who still does everything by the book but the "seasoned professional" who knows exactly what you can get away with when your work only needs to hold 1/2psi.

Like any large accident there are many dominoes that need to be lined up before they can all be knocked down at once. I think it's foolish to act like some contractor dutifully carrying out Colombia Gas's faulty work order is the only cause of this.

Re: Massachusetts gas fires: Another technological tragedy

#100

Post by Piskvorrr » Sun, Oct 21, 2018, 3:13 PM UTC

Scoundreller wrote: post #64

jefftk wrote: post #21

Earlier quoted context omitted.

There are pressure relief valves, but they (a) can't handle that much overpressure and (b) many of them are located inside the houses (at the gas meter, which on many houses around here is still indoors).

The usualy idea of the valves is for them to open before the overpressure exceeds their design capacity. A blow-out disk isn't going to fail to operate. My pressure-cooker has one. It's just a piece of material that will catastrophically open the vessel to the atmosphere before massive overpressurization.

Well...that's a very unfortunate example. Pressure cookers' blowout disks can get clogged by whatever you're cooking (beans specifically) and the whole lid blows out (embedding itself in the ceiling and painting the kitchen). Scary stuff.