201 points by tlb 10 months ago
This is playing nonstop on all local news channels in the Boston area, and the footage is terrifying. One house just blew up, and then residents across a wide area said they heard hissing in their home and fires broke out in 70 of them. A news helicopter circled one of them for 40 minutes before firefighters could reach it, there were just too many other fires and not enough local resources. One of the towns (Andover or North Andover) had 38 fires in all, including 18 burning at one time.
They have a good "mutual aid" system here and fire apparatus from the neighboring communities including New Hampshire and all over the Boston area eventually flooded in to these three cities (Lawrence, Andover, North Andover) to help.
Someone mentioned there have been incidents like this before in Lexington, Mass. The news also mentioned another incident in Danvers more than 10 years ago but that wasn't natural gas, it was improperly stored chemicals: http://archive.boston.com/news/specials/local/danvers_explos...
ETA: An 18 year old died - he was sitting in a car in a driveway next to the house that exploded, and a chimney fell on the vehicle.
Andover resident here. The local response has been super impressive. I've never seen so many emergency response vehicles and personnel mobilized so quickly from so many different places.
We drove north to New Hampshire on instinct as soon as we had a sense of what was happening (about an hour before the formal evacuation), and saw police and firetrucks heading south the entire way. After dinner, on our way back south (not home, but to another place to stay tonight), all the highway exits in the affected areas were closed, with police at each exit offering guidance to drivers who weren't sure what to do or where to go.
The affected communities are suburban -- not in the boonies, but not urban either, and definitely not used to having to respond so urgently to a widespread problem like this. They appear to have been very well trained and ready for it.
This is heartwarming to hear, and not surprising from my experience. Although people are great at minding their own matters in the greater Boston metro and beyond in non-crisis situations, when folks need help, this is a great place to get that help.
>Although people are great at minding their own matters in the greater Boston metro and beyond
No. They are very much are not. Massachusetts people are busybodies compared to people farther north. They very much care about things that others do that don't effect them. It's been this way since Boston was founded in the 1600s and it's deeply ingrained in the culture. I didn't notice it until I lived in northern New England for awhile.
What he means, I assume, is that Massachusetts people are very "cold" compared to people in the South or on the West Coast in the sense that strangers are very unlikely to greet you or chat you up. It always weirds me out when people start doing that but visitors to this area complain about the opposite.
I'll agree with that.
Nobody will talk to you on the subway. Everybody will be very interested on whether your replacement garage door "fits the character of the neighborhood" though. If your kid gets off the bus and lets themselves into the house before you show up from work you are going to get really familiar with the local cops.
My favorite two anecdotes:
I once drove ~1/2mi home after getting a flat (in the tires' defense, it was older than me), mid-morning on a weekday. Less than 5min later, while I was in the middle of "screw these used pieces of shit, I'm ordering all new Firestones on Amazon" the cops, knocked on my door. Turns out someone had followed me home and then called me in to the cops as a possible drunk driver, on a weekday morning. And the cops were happy to oblige. They had no problem showing up and playing the questions game with me over a call they would have ignored in NH or ME.
Back when I was in middle school (decades ago) my parents got lectured by the school about how they were raising me because I kept getting in trouble for using pads of sticky notes to make short animations of car crashes, explosions, and other typical action movie stuff.
If those aren't hallmarks of a society that think's it's perfectly fine to get unnecessarily involved in someone else's problems then I don't know what is.
That seems like a phenomenon of upper-class neighborhoods. My neighbor has a roof with a bunch of missing shingles and has put a tarp instead of fixing it; I doubt anyone is that bothered what I do if it's not crazy.
Try letting a kid play in the backyard unsupervised for 15 minutes and get back to us.
You hear these stories all over the country. It's a sickness but I'm not pinning it on Massachusetts specifically.
> Back when I was in middle school (decades ago) my parents got lectured by the school about how they were raising me because I kept getting in trouble for using pads of sticky notes to make short animations of car crashes, explosions, and other typical action movie stuff.
You have to admit they were on to something though, here you are writing stuff on a forum for scary hackers.
I know someone from the area and she says the impression is Columbia Gas willfully ignored the situation in Lawrence, the poorer of the suburbs, than Andover and the more affluent adjacent towns. Accurate assessment?
It's an absolute nightmare scenario. You can be doing everything right and, whoops, your house just gets blown up out of nowhere.
Does anyone know how you could go about installing your own regulator at your house on your gas line?
Would it even be able to mitigate something like this?
You would need a overpressure relief valve, not a regulator. And it's not clear to me what you would do with the overpressure except either (a) block it to protect internal systems, leaving the externals to fend for themselves, or (b) flare it off via a rooftop vent system, which would be quite hazardous and unwieldy to maintain.
but who doesn't want a flamethrower mounted to their roof?
You already have 'your own' regulator. And it will be as good or better than anything that you are likely to install yourself. Also, having two regulators in series will kill your flow, they need a delta to work with.
What do you think someone does "right" to prevent a gas leak? It's an infrastructure disaster.
If you own a house, you quickly become obsessive about all kinds of maintenance tasks to ward off disaster. And then whoops, one day someone over-pressurizes the gas line and there it all goes in a shower of flames anyway.
> You can be doing everything right and, whoops, your house just gets blown up out of nowhere.
Yes, but this idea of "right" and insulation or exemption from problems is derived from a protestant belief system which is a major part of American culture.
Although the concept can be helpful in navigating life, it is totally unrelated to reality.
I think recognizing how this notion came to be can help with the cognitive dissonance and move you closer to acceptance.
> Yes, but this idea of "right" and insulation or exemption from problems is derived from a protestant belief system which is a major part of American culture.
Yes, who could forget that famous sermon by Luther? I don't know how you figure.
The CSB does great videos after big investigations. They did one on Davers that is worth watching:
I love that youtube channel. I remember coming across a random video once on Youtube then spending a couple hrs over the next week watching them.
All I am going to say is: When those two idiots set off those pressure cooker bombs at the marathon, there was no lack of cops to form an army to shut down the entire city for nearly three days! Screw off, Boston!
I don’t know about the rest of the nation but the natural gas infrastructure in Massachusetts is comically terrible. It isn’t unusual to be walking down the street in Boston (note: a separate utility than tonight’s incident) and to walk into a cloud of natural gas. I had such a cloud on my residential street for years that was strong enough to burn your eyes. National Grid would come by every few months, stick a probe in the ground, and declare it not worth fixing despite our repeated calls. I wonder how much of their product actually makes it from production facilities to end households without leaking out along the way.
You might try looking up your gas company's agent for service of process (Secretary of State site search, probably).
Send a registered snail mail describing the leak in your neighborhood to the agent, copy corporate counsel and at least one local news organization. Major bonus points if you find and copy the gas company's insurance carrier. Emphasize the potential for destruction of property and death of innocents - and the gas company's potential liability. Raise the spectre of California's PG&E and San Bruno.
Management and its insurers care deeply about liability. Old-fashioned paper trails can be surprisingly effective.
> On January 13, 2012, an independent audit from the State of California issued a report stating that PG&E had illegally diverted over $100 million from a fund used for safety operations, and instead used it for executive compensation and bonuses.
That's pretty impressively cynical.
You can now raise the spectre of Andover. :(
Really good suggestion
I had such a cloud on my residential street for years that was strong enough to burn your eyes.
That is the odourant, which fortunately alerts you of its presence and concentration. Pure methane is odourless.
National Grid would come by every few months, stick a probe in the ground, and declare it not worth fixing despite our repeated calls.
To me that just sounds like a huge WTF!?!? If it was lit, would they just come and extinguish it and then leave?
Regardless, I'd consider it a massive hazard to have clouds of flammable gas just lingering everywhere.
There's a 30 year old gas leak here. I've heard there's a group that celebrates it's birthday every year. The op was not exaggerating when he said it was comically terrible.
Im surprised no politician has pushed to get it fixed since climate change is something people care about in the area and methane is much worse for global warming than carbon dioxide
I'll be damned: https://www.bostonglobe.com/metro/2015/09/16/advocates-hold-...
It's like how it's best that some companies or probably even countries are best to stay away from nuclear power: to have even moderate safety requires a certain attitude and ability to organize. If your city or country has a lot of corruption, then it's really hard to have safety because companies get competitive advantage from bribing.
The dark ages are constantly there, just waiting to return.
It's like being a ship on the ocean. You could be lulled into a false sense of safety by the pretty views and the flying fish but death is always right around the corner and waiting mercilessly for you to fuck up every so slightly.
Could barely see the title before being begged for money.
Huh, weird. For me it was the inverse. I barely saw anything but the text of the article, presumably because of uBlock Origin.
It's usually an organosulfur or mercaptan IIRC which humans can detect in PPB.
I think one of the compounds is that which is used in stinkbombs.
PS: Are stinkbombs still a thing in schools? Or has zero-tolerance made that a capital crime too?
There's a story behind why gas is oderised. 295 souls.
This would be considered chemical terrorism nowadays and the perp would get 3 life sentences.
>>> PS: Are stinkbombs still a thing in schools? Or has zero-tolerance made that a capital crime too?
Off topic, but so d.mn right/funny :-)
If this gas supplier thought it could get away with not putting an odourant in the gas supply, I suspect it would do exactly that.
We regularly have the fire department roll up in front of my house to investigate a reported gas leak. One time it scared the crap out of me as I went to let the dog out and there were men on my deck. As it turns out they were from the FD and checking out my grill
At some point I saw a map of all of those mini-leaks which are known and not worth fixing and sure enough one is right in front of my house
I believe there are several efforts, some of them community-driven, to identify and catalogue gas leaks in Massachusetts. Here's one with a fascinating (startling?) map of gas leak locations (scroll down): http://gasleaksclf.org/
I don't call the gas company, I call the fire department. They tend to take paper trails a lot more seriously.
Here in our Seattle bedroom community the gas people are phenomenal, and they deal with every leak, no matter how minor. They will come out in the middle of the night without being asked twice. I am thankful.
In SDG&E territory, I had a plumber notice a leak near the gas meter, and encourage me to call it in. I called it in at 3PM. At 5 there was an initial crew. At 11pm the guys with the real tools came and finished it off, including the use of a jackhammer at 12:30am (you do what you have to do). Then I read about people with gas bubbling up through their lawns in San Bruno before it blew up and I was shocked that the other utility company had such low standards.
Any idea if “National Grid” is related to the British company, or is that merely coincidental?
Yes, I believe it's related. They operate in the northeastern US. They replaced Niagara Mohawk where I live.
Edit: But I don't believe this story is about National Grid.
> Edit: But I don't believe this story is about National Grid.
That is correct - the company that owns the infrastructure where things went horribly wrong is Columbia Gas of Massachusetts, which is owned by NISource (NYSE:NI), which is based in Indiana.
Yep, same company.
Curious how the same company doing the same business can be excellent in the UK and apparently so bad in the US.
Iirc we recently sold the gas part of the national grid to a Chinese company.
Probably different leadership or financials between the branches.
Og regulatory framework European infrastructure operators tend to be regulated to a much higher degree then American standards for business independence allows.
Do a google search for "columbia gas" before today. There's page after page of people being killed and injured in small scale explosions, and reporting severe leaks.
Is this normal for other gas utilities?
> Is this normal for other gas utilities?
I've never heard of "mini gas leaks" that are supposed to be fine until I've seen this thread. Every gas leak that's reported here must be fixed. Gas-related explosions still happen, I'd say it's 50:50 people messing with gas piping and people attempting suicide.
I did a project on this some time ago. Columbia gas was one of the worst offenders for sheer volume of leaks. Not only is it normal to leave leaks unfixed, frequently they disappear from the public record without any recorded nearby fixes.
It'd be interesting to see whether there's a correlation between explosion and leak location.
Overview (just for the Boston Area. I didn't do the analysis for Columbia gas.)
I'm happy to lend a hand for the Columbia 2016-17, and 2017-18 data if others want to join in.
Interesting, what motivated you to do this project?
Some news sites would probably interested in this website/project at the moment...
I'm in Michigan, with DTE Energy gas service. I had an experience a decade ago where they came to the door and informed me that the line needed to be replaced due to a leak. That made me pretty worried, but their nonchalant attitude seemed to indicate that it wasn't a big deal. Turns out (if I understood and remember it properly) that it was a small leak that was known about for some time—it was probably detected by a vehicle that drives around with sensors mapping out leaks.
Both that house and the one I own now are over 100 years old. The water, sewer, and gas lines are, AFAIK, original.
They are subsidiary of NiSource Inc. (NYSE:NI) a huge publicly traded utility. First time I've ever heard of something of this scale that I can remember. Gas explosions aren't unheard of but so many in a small area is perhaps unprecedented.
When i was growing up something similar happened in our town - over pressure caused by connecting a high pressure gas line to the local supply - police closed off the whole town and a few bits and pieces blew up/caught fire.
That was human error rather than failing infrastructure.
My initial thought in this case, before hearing about the underinvestment by the utility company, was SCADA kit tampering/hacking. Running the pressure slightly high would be a very similar approach to the spinning of centrifuges at slightly over speed - not immediately detectable but with serious consequences. Judging by the comments on this thread it looks more like ineptitude/negligence by the utility.
This happened in Lexington Massachusetts a few years back.
It was over pressurization of the gas system as suspected. Any little leaks get magnified.
We forgot how insane it is to pump explosive gas into our houses beacause we’ve gotten so good at it. I was remembering a similar accident near me, and it turned out to be 1982. That’s a lot of unremarkable years in between.
(1982) A state of emergency was in effect today after 28 homes and businesses burst into flames within seconds when the pressure in a natural gas line was kicked up accidentally, causing water heaters and furnaces to spit fire like "blowtorches."
As much as I love my gas stove, part of me can't help but think that we mostly won't be running gas lines into new houses within a few decades. Both gas and electricity can kill you, but a closed pressurized system of flammable gas is just harder (and more expensive) to engineer, install, and maintain than a wire run. But now I'm curious as to what sort of huge increase in power generation capacity it would theoretically take to cover for what gas heating currently provides...
In the process of moving to renewable energy, The Netherlands has banned natural gas connections to new houses starting 1 July 2018. This is even though the country has one of the largest gas fields in the world . Electric (induction) cooktops and district heating are very good alternatives to using gas (and safer, even though the gas infrastructure is very good).
Much like the biggest farm is not necessarily the most profitable, the Netherlands government reporting office claims peak production was a decade ago, and its all downhill until the mid 2020s (lets say, five years away?) when the Netherlands switches over permanently from being a net producer of natgas to being a net importer.
Kind of like how the UK peaked around the turn of the century and has been a net importer for more than a decade, but delayed by maybe 15 years.
In this line of business (IT) its all about scaling. The economic models around natgas are hilarious in that nobody scales beyond one, at least in public. So every country on the planet has a natgas economic model where on a scale factor of one, the permanent transition from exporter to importer is "no biggie" because there's an infinite supply of infinite cheap commodity natgas from world trade, so we'll just have some ... permanent inflation from printing money to import all that natgas. That economic model sounds really good scaled to one country, but doesn't work well when scaled to "pretty much every country on the planet at the same time and the global cheap commodity natgas market disappears".
There's probably a lot of startup opportunity in "residential natgas disappears".
What are we going to do with all those dormant pipes? Could some clever startup use them to route physical packets of stuff? :)
Gas pipes don’t have very large diameters. That being said, they could be used to route fibre optic cables through without digging.
Natural gas stoves used to give me the willies. Then one day the big bottom square heating element in my electric stove started making a weird noise. I opened the oven and looked at it for a minute and the thing exploded! In a million years I wouldn’t have thought it was possible.
Fortunately I didn’t get hit by any shrapnel. And I got a new oven out of it, which was nice. But now I’m afraid of both cooking methods.
However, your house was still standing.
We're living in the peak right now of natgas so its no surprise in a couple decades the general public will not be using natgas.
Discoveries peaked in the 70s, normal production peaked a decade ago, strange fracking experiments to squeeze the last blood from the rocks is peaking "around now ish".
Natgas is vastly more useful to make plastics and fertilizer than to run my clothes dryer, and global demand is completely unconstrained, and economic conditions such as income inequality, demographic changes, etc are only getting worse, so its not controversial at all to claim in a couple decades your average house will not have natgas service.
Generally its cheaper to install insulation and better windows than to install more electrical generating capacity. Probably cheaper to install insulation and a heat recovery ventilator than to install natgas fuel-cell cogeneration plants in each basement or triple the number of nuclear reactors.
I would imagine this ties into long term planning such as chopping maintenance budgets. If buried gas lines can't be maintained to any standard other than lasting the next 80 years at great expense, and corporate strategy indicates not enough end user consumers will be able to pay $2000/month inflation adjusted to heat their house in twenty years, then just pencil whip the maintenance until the service shuts down.
You can see the future of residential natgas in the past of dairy milk delivery, ice block delivery, to some extent postal service, land line phones, and cable TV. You can expect a lot of gas-lighting (oh the pun) about how the replacement services are so much better (solar heating, insulation, etc)
Personally I suspect a lot of the diehard adherents to gas cooking haven't had a chance to cook with a modern glass top resistance or induction stove. IMO the difference has shrunk dramatically.
Water heaters too, electrics have improved and the operating cost difference is really not that big. Electric water heaters might also be extremely valuable for demand response.
When it comes to space heating in cold climates though, I don't really know what replaces natural gas. Probably air source heat pumps, but they are still maturing.
Gas infrastructure works when the power is out... It can't survive all natural disasters, but some.
When it's -6 degrees outside and you have hot water, heat, and a fireplace that are all still working you'll get it real quick.
A furnace does require a generator to run the blower, but it can be a pretty small one and it sips fuel.
That's the thing, I've never lived somewhere that gets to -6 and also runs a real chance of multi day power outages.
I'm sure it's a different story in some parts of the world, of course.
FWIW, I don't think we have ever run gas lines to individual homes in large scale here in Finland, and we are obviously in a heating-needed region.
Natural gas is 7% of the total energy consumption here (https://www.stat.fi/til/ehk/2018/01/ehk_2018_01_2018-06-27_t...).
There are 30.000 homes that have gas connection for cooking, but that is a small fraction of the ~2.700.000 households in Finland (
Gas is used for heating, but it is mostly via CHP (Combined Heating and Power) plants that heat water in a district heating network ( https://energia.fi/en/energy_sector_in_finland/energy_produc... ,
For single detached houses, for new houses the most common main heat sources are ground heat (52%) and air heat pumps (18%). with other options being electricity (8%), district heating (9%), water heat pumps (8%) and wood (5%) (Finnish: https://www.suomirakentaa.fi/omakotirakentaja/laemmitys/laem...).
As for existing single detached houses, the most common sources are 44% electricity, 21% wood, 16% oil (Finnish: http://www.stat.fi/tietotrendit/artikkelit/2018/uusiutuva-en...) .
Energy consumption in households by energy source, type of use, type of building, GWh: https://www.stat.fi/til/asen/2016/asen_2016_2017-11-17_tau_0...
Nuclear. Of course big petroleum and hard-left greenies joined forces to kill it before it brought us into the future.
To be clear here, you are saying nuclear generators could have replaced gas stoves and gas water heaters?
I don't follow, surely this is a magnitude more risky than nuclear power plants, and way riskier than gas heaters.
Electric water heaters do exist after all.
I’m pretty sure the poster is saying nuclear power would help provide the additional electricity needed at a plant, and not in individual’s homes, as you seem to suggest.
why not a network of pressurized liquefied nuclear material similar to gas heat? distribute the steam turbine system such that each house uses only the radiation it needs
> We forgot how insane it is to pump explosive gas into our houses
Yet mention that we could have solar panels and batteries for local storage and people will say "we can't have huge banks of batteries in our houses, think of the fire risk!"
Seems like some of the very people affected have embraced solar power.
We forgot how insane it is to pump explosive gas into our houses...
Here in the developing country where I live the locals think Americans are insane for doing this. When I first moved here I thought they were backward because there is no gas piped around. It's all portable refillable tanks that you buy at the corner shop and hook up to your stove. Seems like a recipe for disaster, right? Well yes, there are accidents and an explosion now and then. But it's limited to a single house in most cases. They don't have whole neighborhoods erupting due to failing infrastructure. So maybe I'm changing my mind and being less developed has some very real advantages.
The US is not unique here. I suspect you'd find that an even higher percentage of homes in the UK are connected to gas lines.
But these types of explosions are extremely rare, and most likely you'll find more accidents in less developed countries from people connecting the tanks incorrectly than you'll find from instances in the US, UK, or other countries of massive accidents like this one.
I mean if you prefer that look for a house with oil heating, but it costs a fortune.
I made a terrible oversight. Where I live there is no need for heating. Gas is only used for cooking. So my previous comment does not apply to a huge portion of the population. My bad.
Oh. Well... if you have oil heating (or no heating) you probably have an electric stove. I don't think I've ever seen a house with a gas stove that didn't have gas heat.
If you don't have gas heat, you can get a (large) propane tank for use with a gas stovetop. My first house had such a setup (oil heat).
Hm. That's new to me. Seems like more trouble than it's worth.
Some people are really attached to their gas stoves. I have seen this setup in western Massachusettes where gas-lines are not available.
Where I live [not the US] gas cooking is very common but heating is most commonly done by either heat pump (air conditioner set to reverse) or kerosene.
I think the same about electric car batteries: people fear the volatility of those only because we’ve gotten used to driving around with tanks of the most explosive liquid we have.
The previous state of the art was open flame.
Maybe this is a dumb question ... but shouldn't the regulator on the side of my house prevent a system over-pressurization from affecting me?
Yes it would, but part of that is that above a set pressure they can start venting.
The idea is that an increase in pressure relative to ambient will cause a needle (low flow) or disc (high flow) valve to open or close, pressure in the pipe higher than the desired delta will cause the valve to close and vice-versa.
The venting is a safety measure to protect downstream equipment in case of regulator failure (for instance, if it seizes too far open, or the seals are porous and the consumers are all not using gas which would slowly cause the pressure in the house side to rise to the same pressure as the feeder line), and normally this would be to let little bits of gas escape, but if the line pressure were high enough it would allow a constant stream of gas to escape from regulators that were 'borderline' or seized up. It could also cause the membrane under the spring to break, and that would let even more gas out through the seal between the tap stem and the regulator housing, and any consumers that were 'on' at the time would have to deal with the overpressure directly which they would not be designed for. They can handle a bit of overpressure but not for ever and not beyond certain set limits. Especially aluminum burner housings would simply burn up after some time.
In some lines there are burst plates as the final safety, those really should never go but when they do it is definitely a spectacle if there is an ignition source nearby. A burst place is a purposefully weakened structure that is bolted (with a seal) on top of a gasline so that when the pressure increases above the burst plate's rating the plate will rupture. This does not self reset for obvious reasons and will need an on-site technician to repair and would come with a serious investigation into what went wrong upstream.
There is also the opposite device, an emergency shutdown valve that automatically closes when the flow gets either too high or goes negative. The former to ensure that a ruptured pipe will not vent enormous quantities of explosive gas in to the atmosphere, the latter to avoid having an air/gas mixture in the lines.
Gas infrastructure is quite interesting, and very expensive to install and maintain.
Up to a point, yes. But fundamentally a regulator consists of a pipe in and a pipe out with a valve in the middle controlled by the downstream pressure. A high enough pressure in the input pipe can rupture the valve seals (which are rubber). Then the full pressure goes into the downstream pipe (which isn't rated for high pressure) and it leaks.
The system should have safety overpressure relief valves, but obviously something went wrong.
> The system should have safety overpressure relief valves
It does, but those will vent to the atmosphere, if there is enough overpressure and it lasts for long enough the amount of gas released would be considerable.
The whole thing sounds as if that is what happened, an overpressure situation lasting longer than a few moments allowed weak spots in lines and homes to fail leading to fires and explosions.
What? How come the over-pressure safety equipment is not simply locks down the pipe, building backpressure to let the other side know about the problem? Or no such passive device is possible?
The over-pressure protection sits on the far side of the pressure reducer.
Imagine a tube that should be at 1.2 atm, and a feeder line that is at 5 atm. The equipment and the lines on the far side of the regulator may be able to deal with 3 but no more than that. If all the consumers are off and you do not bleed excess gas from the bypass leakage into the atmosphere the pressure on the far side will slowly increase until it is 5 atm, the pressure of the feeder line (no seal is perfect). So you need some way to get rid of that, and normally that is what the vent does, so it will allow miniscule amounts of gas to pass out in order to not let the far side go overpressure.
But if the feederline suddenly jumps to 10 atm, ruptures the seal or if the regulator sticks 'open' when that spike happens then the only thing that stops your internal line to go to that pressure is the bleeder (and in extreme cases, a burst plate that will break). This would allow a lot of gas to be released.
This is also why in some countries regulators are installed outside of the house rather than inside.
Another avenue for gas to escape if the seal breaks is the atmospheric port that allows the pressure of the chamber on the atmospheric side to be the same as ambient, in a sealed housing that would not be the case. Gas pressure regulation is not just about reduction, it is also to output a fixed delta relative to ambient otherwise your stove would make much larger flames if the atmospheric pressure was low!
Those regulators are works of art, totally passive and yet with a whole raft of features.
I am surprised that only some countries require the regulator to be outside. Just seems like a relatively simple thing to do. Does having the regulator outside require more maintenance or something?
You have to remember that natgas is extremely old, like mid industrial revolution era. Homes had natgas before they had electricity, usually.
In the early days they billed on the number of gas jets for illumination but once gas stoves and furnaces became a thing they needed some way to measure, and there's some weird technology out there involving something like an archimedes screw sitting in a couple inches of anti-freeze driving low friction clockwork. Now a days its probably optical sensors instead of clockwork but whatever.
Two engineering topics are being missed; flow rate thru an orifice is strongly non-linear, and there are no hermetically sealed large scale transport technologies. Its staggeringly impressive that like 99% of electricity pumped into the grid makes it out the other end. Its not practical from an engineering standpoint to operate a leak free material transport pipeline. There's plenty of engineering guidelines such that a leak rate ten times lower than could theoretically cause an explosion is quite acceptable, until some idiot accidentally applies a 10x overpressure forcing open orifices permanently and increasing the leakage flow rate 200x and then kaboom.
Its kind of like automobile gas stations... it would be nice to never have a leak and LARP that we'll be very serious and studious about never having a petroleum leak, but that mindset leads to design and operations decisions which become environmental disasters when the inevitable happens. Better to build everything with the assumption the underground tank will leak one liter per month than to plan the leak rate will be zero. Also no level of idiot proofing is perfect; that leak-tolerant station design will still fail if some truck driver pumps 2000 gallons into a 1000 gallon tank while not paying attention.
There's also safety tolerance / clickbait issues. Natgas averages about ten customers dead per year in the USA. Its very difficult to get stats for in-house mis-adventure but it seems about three hundred die per year from in-home electrocution, so its kinda a rounding error. Food related illness (food poisoning leading to dehydration leading to death) kills about 5000 per year in the usa per google (which seems high?) so you're about 30 times more likely to electrocute yourself at home than die in a natgas explosion, and 500 times more likely to be killed by whats in your cooking pot than whats heating your cooking pot. Given that, more investment to prevent natgas deaths would likely result in more deaths from other causes; taking money away from "stop drinking corn syrup" or "cook meat to 165F" will kill more people than a 10% improvement in long term natgas death stats would save.
It seems one solution might be to have a small constantly-burning flame (the other posts here that say small gas leaks are basically being ignored suggest that it wouldn't really cost much more) at the relief valve exits, so that if they vent, the excess gas just gets burnt. Obviously the relief valve exits should be located away from flammables, and preferably visible so that extended overpressure events are immediately noticeable from the flames coming out:
The goal is to not silently create an explosive mixture, but to burn vented gas to make it harmless and create a visible indicator of extended venting.
> It seems one solution might be to have a small constantly-burning flame (the other posts here that say small gas leaks are basically being ignored suggest that it wouldn't really cost much more) at the relief valve exits, so that if they vent, the excess gas just gets burnt.
When the amounts are larger that is exactly how it is done. But for trace amounts the mixture would not reach a concentration level where it is combustible and then you need a whole setup around that to batch it to the point where it is.
Hard to do that passively, also, you could no longer do that indoors.
In legacy “low pressure” systems, regulators aren’t used at the residential end at all. Our neighborhood was recently upgraded to a “high pressure” system, and regulators were introduced, along with vents cut through the foundation to the outdoors.
Our neighborhood was built in 1950. This system upgrade included replacing all the mains in the road as well.
I don't know exactly how the safety systems on gas work, but its a good question.
I saw it mentioned elsewhere in this thread, but it may be worth noting that there has been a lockout of National Grid workers since June 25th. These workers serviced "700,000 gas customers in 85 communities in eastern Massachusetts", NGrid has replaced them with contract workers to continue service.
A site representing the union states that those locked out "do the critical work of maintaining natural gas lines for homes, schools, and businesses across Massachusetts"
Unsure if this is related to the current incident & Columbia Gas
edit: Press conferences seem to indicate that Columbia Gas is responsible for this region and not National Grid. Seems Unrelated
This wasn't National Grid's gas line. It belonged to Columbia Gas.
I don't think its related.
Not just Massachusetts -- a similar incident happened in the SF Bay Area a while back: https://en.wikipedia.org/wiki/San_Bruno_pipeline_explosion
The pipeline dated back to 1956.
If you think about it: highly flammable/explosive substance transported under high pressure 24/7 in decades-old infrastructure -- it's amazing there hasn't been more accidents.
I am wondering if Watch_Dogs-style cellphone-controlled terror might become reality soon if hackers manage to control gas companies' pressure systems; they could truly cause devastating blows to arbitrary cities with very little defense against and limited tracking back to perpetrators.
Stuxnet is the same idea. But really hackers are unnecessary when you have shoddy workmanship and lax regulation.
MA is not exactly the first state that comes to mind when one say "lax regulation."
We share a border with a state that prides itself on not over-regulating things and their houses aren't blowing up.
This is just the product of good, old fashioned incompetence and apathy from top to bottom.
I mean, Massachusetts is better than others. But that doesn't necessarily mean all the regulation is robust.
I hope this isn't an obvious question: Why aren't there safeties in the system to control these kinds of problems?
For example, I have a giant gas meter outside my home. How come it can't turn the gas off when the line is over pressure? Massachusetts state law requires that the gas company change it every few years. (I'm a MA resident)
My breaker box will turn off if there is a fault.
Couple of thoughts about gas and electricity and the similarities and differences:
- an overpressure situation is specifically trying to blow through whatever "off" means (e.g. a ball valve or whatever the valves are). If the pressure rises too much, that valve is going to fail. That's true of circuit breakers too, but the "overvoltage fault voltage" of a circuit breaker is likely going to be way way way higher than anything you could reasonably expect from the grid, although lightning could probably flash over it.
- Your breaker box will turn off during certain forms of fault, but not all. A line overvoltage probably wouldn't trip a breaker until the line voltage gets high enough to cause a fault in some piece of equipment connected downstream of the breaker (e.g. it blows up a switching power supply in your house and that fault current trips the breaker)
- In the gas overpressure case, if all of the houses had gas meters that automatically turned off... the pressure in the community gas line would rise higher and higher. This is going to sound a bit cold, but it's likely better to have some houses blow up due to overpressure than to have a gas main explode after all of the houses have already shut off the gas.
Bad situation all around :(. While acknowledging that I'm not a Mech E, my guess would be that the best solution would be to have periodically-placed blow-off valves on the gas main that could flare the gas if there were an overpressure situation. You don't really want to just release it, because then you've got a cloud of gas floating around that could get ignited by... whatever random ignition source.
This is probably a stupid idea, (I know absolutely nothing about natural gas) but why can't we emergency vent the gas outside?
My gas meter is already outside the house, more than 30 feet away from anything flammable. In an emergency overpressure like this, shouldn't I be able to pull some sort of emergency lever to vent the gas outside.
Yeah, that gas is flammable, which is risky. But that has to be less risky than just sitting around waiting for my house to blow up, which seems to be my only option today.
If your gas installation is anything like mine, you could go outside and shut off the feed into your house. There's a valve that you could turn with a crescent wrench. Mine, at least, has a hole in it that the gas company can put a lock through when the valve is shut (which is what they do when they cut off your gas service).
That way you're at least not going to have the inside of your house fill with gas.
The trick with an overpressure gas main is that pulling that lever isn't going to be a "gas vents off for a few seconds and then things are good again" event. You won't be just reducing the pressure for your house, you'll be reducing the pressure for your entire neighbourhood, and there's going to be a pretty significant amount of gas that needs to vent.
Also, I'm not sure if this is the case with methane, but propane has a really fun property... Going from compressed/liquified propane to gas propane has a high enough latent heat of vaporization that it can cool the surrounding liquid enough to freeze it (!!!). There was a court case around here a few years ago with a propane truck that blew a valve and started venting propane to the atmosphere. The liquid->gas transition cooled off the valve so much that a solid propane plug formed and stopped the leak (-188 degC!). Temporarily, of course... the plug eventually thawed, the gas continued escaping, and things got bad again. Having devices that could experience similar behaviour installed at peoples' homes seems pretty dangerous to me.
It's all a shitty situation. Really, this is on the gas company. Their pumps should have never gotten the lines pressurized like this, and they should have had mechanisms in place to vent it in a controlled and safe fashion.
There are lots of such safeties in the system, it's just that unlike electricity an 'open' connection in a gas line is called a leak... So the problem is much harder, and there is no safe configuration where you can force a valve to shut down in a passive way if the other side is not playing nice. Above a certain pressure anything will go and to design for even higher pressures would be cost prohibitive. So burst plates and other non-resettable safety devices are deployed in strategic locations, and their default mode is to vent.
What exactly went wrong here is still unknown but the smart money is on an uncontained overpressure and a failure of one or more safeties. All it takes i the right set of circumstances. For instance: a very short pulse of very high pressure followed by a lower pressure not high enough to cause venting to occur. That would do nicely: every membrane in the line that was at or near the end of their service life would break causing high pressure to end up on the low pressure side but it would not cause the main safeties to trip.
Keep in mind that all this stuff is passive, mostly mechanical and in many cases decades old.
Something similar can happen to circuit breakers: there is an effect that causes the breaker to weld itself into position rather than to break the circuit, and there are plenty of examples of the breakers themselves catching fire due to high resistance between the breaker contacts. Then there is lightning, which can zap your house to the point that your electronics gear is nicely plated on the inside of empty casings and the breakers are all still sitting there as if everything is fine.
It is super hard to create a safety system that will always work under every circumstance, especially if you want to do this maintenance free. More so, if you did not design it maintenance free but someone decided to skip on the maintenance.
Or ya know put the gas meters outside so they don't vent into a confined space when the regulator seal fails
The gas meters are outside. (MA resident here)
> My breaker box will turn off if there is a fault.
If this was infallible there wouldn't be a market for surge protectors
The US really need to get their shit together with how the taxes are used. Dams, roads, bridges, pipelines, water cleansing... All that needs maintenance and it is not being done.
Tell me about it. In 2007, there has been a bridge collapse that was mostly caused by inadequate maintenance. Two others (more recently) were accidents. And these weren't some little bridges in the middle of nowhere. They were heavily used interstates (sometimes crossing rivers). You can't miss them.
I live in a city that has three major rivers in it, and more bridges than any other. Things like these give me the willies.
Look, it's not like all those countries are going to bomb themselves.
You're comparing apples to oranges. Gas lines, electric lines, and telecom infrastructure is usually privately owned (or through a limited public utility), so your taxes don't fund maintenance for them.
It sounds like you're making an argument against private utility companies
Infrastructure in the US is really old and very dangerous. 100+ years old and ready to fall apart. Sadly, not really surprised.
From what I understand, some repair work was being performed. Apparently the gas infrastructure there is some of the oldest in the nation.
I used to live in Andover, MA in a prior existence, and while the town is very rich it is also as they say, very historic. I wouldn’t be shocked if the infrastructure was ancient. As for Lawrence (disclaimer: it may have changed) it was a seriously poor former mill town, and I wouldn’t be shocked if their infrastructure and services were in awful shape.
Not knowing any better, I could only guess something similar to the San Bruno gas explosions a couple of years ago which were caused by aging and poorly maintained mains gas pipes.
Can only hope the damage is contained quick.
From 2016: Methane Hazard Lurks in Boston's Aging, Leaking Gas Pipes, Study Says https://insideclimatenews.org/news/30032016/boston-natural-g...
Something similar happened in Chicago in 1992.
This is just bad infrastructure design. The gas line grid should have a safety vent that blows open in an abandoned field at some pressure between the operating pressure of the line and the maximum pressure the houses can handle.
Natural gas infrastructure in New England and MA in particular is horrible. A big part of the reason why prices remain high (3-4x vs New York) in the region despite the recent fracking boom. Incidents such as this do not help.
As I recall the biggest thing was that the pipelines are insufficient and so in the winter it has to be shipped by sea.
Security people, any chance at all this was caused by hacking some utilities SCADA somewhere? Tell me the Russians or the Chinese can't turn our houses into bombs...
Is there any possibility that this was caused by hackers?
That idea has been floating around a lot. It's definitely not outside the realm of possibility, though what makes me think is was human error is the fact that Columbia Gas (company responsible for those lines) publicly announced work on the lines about a week before this happened.
I could also be that a week before the hack started. I know that my line of thinking is very "Mr Robot". Let's hope it's not a hack and it's just human error.
Hasn't there been a lockout of employees for a while, and folks were getting replaced by scabs?
All I can find is lockouts of National Grid workers and replacing them with scabs. They news is reporting that these are Columbia Gas lines.
Different company. You're talking about National Grid, this is Columbia Gas of Massachusetts.
This is just FUD and conjecture - this isn't reddit, it's ycombinator.
Reading some of the FUD and conjecture I thought maybe I was on reddit for a second...
terrorism hacked gate system?
It was the Russians!!!
They're clever, to hack the utility with the worst safety record and crappiest infrastructure...
Terrorism? Hacked gate system Stuxnet virus?
We've missed you Kaczynski.
By close of business Friday the plumbing lobby will be saying this is because people did their own gas lines and requesting laws to drive them even more business. They'll probably get it too. By Monday everyone will have forgotten. Maybe there's be some hand wringing and an investigation. Not an extra cent will be allocated to fixing the infrastructure or processes that failed and led to this. That's how things work in this state, but hey, at least there's a few high paying jobs in Boston and we have progressive politics so we'll just keep patting ourselves on the back about how great it is to live here.
We don't know if the cause is hacking, but it's likely that gas main pressure is controlled by a computer. It'd be shocking if a software failure could cause dozens of fires.
> We don't know if the cause is hacking
> but it's likely that gas main pressure is controlled by a computer.
But the failsafes are not. Overpressure is something the system is designed to handle, and those gas substations that you see every now and then in fields are the places where the overpressure regulation devices are located, and they are purely mechanical.
> It'd be shocking if a software failure could cause dozens of fires.
It would be, but this isn't that. The actuators on these systems are made with the express purpose that line fluctuations will always be slow enough to catch up with. But if a regulator fails in a bad way that might cause a prolonged overpressure with the initial change arriving as a spike, which may expose further weaknesses downstream.
So the signature of an upstream regulator failure (a big one, and a sudden one too), is fairly consistent with what you are seeing here. The software actuators would not cause a pressure rise fast enough for that initial spike and the limit settings on those actuators (which are mechanical) would not allow those actuators to move beyond certain minimum and maximum set points for each line that they service.
The people that designed these systems were anything but stupid and it is failsafes layered on more failsafes, the big killer for systems like this is a very simple one: back maintenance.
I'm curious why you seem to be speculating/implying that this was a deliberate "attack"/act of terrorism, when the linked article doesn't mention anything of the sort.
Your comment seems to be implying that there is some sort of evidence of hacking here, which, unless I'm missing something, does not seem to be the case.
I'd speculate that the simplest root cause might be an system overpressure. Any hookup to a valve that couldn't contain a pressure of some level could be susceptible to leaking gas onto an ignition source which could then start a fire.
It's surely overpressure, beyond what the regulators at each house can hold back. The question is why, and whether such a thing could be caused by hacking a SCADA system.
A gas explosion (claimed to be among the biggest non-nuclear explosions) was caused by the CIA hacking a soviet pipeline:
It’s peculiar to me that you have repeatedly attempted to create a rumor that it was hackers even though there is no evidence to support that. Are you playing at something or just enjoy spreading misinformation?
What seems strange is IF someone had root on a enemy nation's natgas distribution plant, a short spike resulting in a handful of explosions is the third least effective attack I can think of (the least being doing nothing, second least effective being some kind of blackmail attempt). Performing almost any other conscious action would be more destructive to life and property and economy. Therefore unless its literally accidental (like the SQL slammer attack decades ago causing DOS via flooding) there almost certainly can not be hacking / terror involvement.
Yet its also too destructive and attention seeking to be a plausible threat or sending a message; if outsiders messed with the SCADA to do this, fifteen minutes later all the passwords would be changed and sites physically locked down, such that a threat to do something more destructive next time (or else..) such as flicking the gas supply off for a couple minutes would be a non-starter. You have to look at it militarily like a stealth attack; giving away your position is not a wise first move if your whole strategy is stealth. You get one shot and this would be an intentional miss, so ...
This would also imply its not an inside job; an insider would know that in my state (admittedly not MA, thankfully) an interruption in pressure requires an attempt at physical access by a rep with a leak sensor to verify pilot light and pilot light safety interlock for EVERY point of use and/or door tag notification warnings. Its happened to me a couple of times for some street work replacing pipes and replacement of my old meter. Its kind of an expensive labor job, a wealth transfer from the company to the union. The fact this didn't happen kind of exonerates the union.
So rule out outsiders and insiders. A nutjob would probably drive a truck into an above ground facility, or frankly, just drive into people, so its probably not a nut. Not many options left. Space aliens did it accidentally? Maybe they closed down that solar observatory in NM because the space aliens are coming to mess with our delicious natgas.
SCADA does not imply the ability to remotely move mechanical parts to result in a negative condition in the pipeline system.
I didn't know the CIA did that, thanks for sharing.
No idea what caused today's explosion, but the USA is clearly not without enemies and vulnerabilities in its own infrastructure.
You'd hope that there'd be mechanical, non-hackable safeguards in place to prevent obvious over-pressure situations. Why would any part of the system allow a serious over-pressure that would result in catastrophe like this?
There are, but one of their safety mechanism is that excess pressure will lead to venting and that in turn can lead to fire if it happens enough. A tiny bit of venting is harmless but a lot of it over a short period of time can cause dangerous concentrations of gas mixed in with regular air, and that is a very nicely combustible mix.
No, it's probably controlled by good-old-fashioned mechanical regulators...
...and the cause may be as simple as the regulator valve sticking open for some reason.
The main reason why that usually happens is if the pressure is extremely constant for a long time, this can cause the valves to seize up and not function properly when they are needed.
LOL SCADA? You haven’t been involved with infrastructure in MASS have you?
Let’s put it this way: it wouldn’t surprise me, especially in Lawrence, if some of the gas mains were still made out of wood. Before you scoff, NYC replaced the last wood gas main that they knew of 25 years ago, but they still occasionally find wooden pipe in their systems.
The best way I’ve heard the gas infrastructure described is “antiquated ... if it was aged, it could be updated and replaced, but it’s so antiquated all that can be done is patchwork because there’s no time to do anything but.”
the last woooden pipe in Philadelphia:
If it was Russia trying to send a message, you'd think they'd have done it on an election day. Still though this is pretty crazy, especially given that most buildings in NYC have a gas hookup.
1). Blame 50 years of infrastructure neglect to the point that the US is ranked a D+  in infrastructure.
2). Blame a country with the population of Nigeria, the GDP of Italy and the military spending of Suadi Arabia?
Could go either way. U.S. infrastructure is terrible and getting worse, which is why the country is collapsing. but (IIRC) natural gas hookups aren't one of the issues that that report emphasizes.
If one building exploded due to a leak then clearly that points to decaying infrastructure, but if dozens of houses explode due to overpressure then that seems more ambiguous.
>Could go either way.
No it couldn't.
That you and some number of other people think it can signals a truly disturbing disconnect from reality on par with global warming denial.
Nuclear powers do not interfere with each others civilian infrastructure.
> Nuclear powers do not interfere with each others civilian infrastructure.
You have to be kidding.
Tell that to that doctor currently in prison in Pakistan for helping the US run a completely fraudulent public health vaccination program. - https://en.wikipedia.org/wiki/Shakil_Afridi
There is also the US blowing up that USSR gas pipeline that tlb linked to - https://www.telegraph.co.uk/news/worldnews/northamerica/usa/...
Then there is the recent reports of Russian infrastructure hacks on a whole range of US industries - https://www.bloomberg.com/news/articles/2018-03-16/russian-h...
And then of course, there is the ultimate infrastructure hack - https://twitter.com/realDonaldTrump
Though that is probably just tit-for-tat, after the US assistance in the career of Boris Yeltsin.
>Tell that to that doctor currently in prison in Pakistan for helping the US run a completely fraudulent public health vaccination program
>There is also the US blowing up that USSR gas pipeline that tlb linked to
Counter industrial espionage.
>Then there is the recent reports of Russian infrastructure hacks on a whole range of US industries
Industrial espionage is confirmed, industrial sabotage are wild speculations with no proof behind them.
> And then of course, there is the ultimate infrastructure hack
Snark aside if you genuinely believe this you are helping delegitimize all US institutions. This is birtherism 2.0.
You're just changing infrastructure attack to industrial espionage. You calling it something else doesn't detract from the point that it's been done, and it was targeted at one country or another's infrastructure.
Nukes don't deter infrastructure attacks. They ENCOURAGE them. Cripple your opponents ability to maintain his arsenal and coordinate his forces, and you could shift the odds of pulling off a crippling first strike immensely.
I am genuinely terrified that there are apparently a number of people who share this attitude.
Here's hoping none of you are anywhere near the leavers of power because this is far more dangerous than garden variety doomsday delusions like Jesus returning, or ignoring climate change.
> If it was Russia trying to send a message, you'd think they'd have done it on an election day.
Today was the NY primary election, which includes a progressive AG candidate vowing to take on Trump at a state level as a bulwark for the federal investigation.
(I think it's extremely far-fetched, but just figured I'd point that bit out.)