What's not mentioned is the age of the presumably outdated and outmoded cast-iron piping, presumably from the initial installation. The code being 100 years old or thereabouts is already mentioned. This is an area with extreme seasonal temperature differences and over time, that aging metal piping was undergoing a gradual metal fatigue. Posters below mention, if extrapolated, the main lines from the utility pushing the flamable, combustible natural gas along at 75 PSI until it hits stepdowns at the regulators to 1.5 PSI after the regulator, and reducing further to .25 PSI on entry into the homes and their appliances. So there is the temperature change factor and the huge PSI differentials along with the aging of several critical parts that were pretty much installed and forgotten about until someone got the bright idea of upgrading the piping and so they did exactly what they were told or paid/.contracted to do and so this is easily seen as "accidents waiting for a place to happen." Alongside the obvious need for more timely updating of the components, wouldn't it be wise to do the work in the warm months, where the gas could be shut off with minimal discomfort and inconvenience to the customers and change out the piping along with the outdated meters and regulators, and/or add said meters and/or regulators to update the entire fuel delivery system to customers in a smaller "block" of homes until the project was completed, along with documenting everything that was completed along the way (as well as which homes were awaiting these service updates)? It all looks so slipshod to me and all that considered it's amazing that explosions did not happen much sooner. Based on the comments of the NTSB it seems they need their department expanded. I fear there are more disasters or "accidents" than they can keep up with, hence the public waiting much longer for their findings, recommendations and the implementation of these recommendations.
FYI. To those who thing regulators on appliances would stop explosions , the fuel lines will leak at 70 psi because they were only designed for 0.25 PSI. Over pressurizing causes leaks on gas pipe.
@@BustedWalletGarage ok, well then the rest of the country is sort of boned. Pretty sure to code gas line in California would take it. Certainly the line running to the houses.
So the pressure sensor for the regulator was connected to a gas line which was then capped, and drained of all natural gas. The regulator, seeing the low pressure from the sensor as the capped pipe was depressurized, started to open to boost pressure in the system... Since the sensor wasn't connected to the system at all anymore, it just kept on opening until it was pushing 75PSI of gas into a system meant for 1.5 PSI...
I'm a natural gas design engineer and project Mgr., regulator inspector, distribution company, very familiar with these types of systems. And ready to retire. I've seen a lot over the past 50 years, but there are still a few things I don't quite understand about this incident. First, almost without exception, any given regulator's sensing lines (in this type of installment) terminate at a certain number of pipe diameters downstream of the regulator; often this distance downstream is only inches away, sometimes several yards or more. Are the authorities saying that a new length of pipe was installed at the station outlet, near the outlet block valve (outlet shut-off valve), and that the sensing lines were never considered as germane to the system's operations? If that's the case, this was a fail of epic proportions. I've never met a regulator technician who didn't appreciate the critical nature of this circumstance. It is, in my experience, always topmost in the minds of operations technicians and station engineers. Further, for the new tie-in to be made, one presumes that the station valves would have been shut off and later re-opened. In my neck of the woods this is always done by a qualified regulator technician. What happened? This boggles the mind. I can't accept that we know all of the facts on this, but if we do, and this is how it came to be, then someone was asleep on the job. As to PRVs (pressure relief valves), don't be fooled: they are the only known means available to act as a fail-safe for a system, despite their annoyances. It is rare for a PRV to "catch fire" upon the release of gas, and even if one did, it would, if properly engineered, serve as a flare until someone could shut down the system. Yes, there is always a risk, but it's an absolute certainty that without a PRV system in place then accidents like the one in Massachusetts will happen, and who wants that. For LP systems, my favorite, tried and true PRV is what we used to call an "oil seal." I love them. I would recommend to Congress that all LP systems have these in place, and that they require annual inspections and maintenance. These have ZERO mechanical parts. They let the laws of physics do the heavy lifting. They're cheap to build and install, can be done through a vendor or in-house, and could save a system like the one at Lawrence. It's a damn shame they didn't have some PRV system in place; their Monitor-Control systems are good for keeping steady pressures without losing a system to troubles on the station inlet side of things, but once pressure enters the line for whatever reason, as it did here, only a PRV will give the gas company some control of the escaping gas. Why leave it to chance?
I'm an engineer in the industry too and I agree with your thoughts. But also, what about the monitor reg? A single regulator is not an adequate means to manage pressure.
I am not sure if it is clear from the press conference (given that it was geared towards layman's terms and light on configuration/operational details) if there was an operating regulator monitoring system in place. I've worked around hundreds of monitor regulator systems and can attest to their overall reliability as an over-pressure option...IF they are well-maintained. I agree, without wanting to rush to blame; that a regulator field technician would/should have been involved in the return to service and thus have a situational awareness of the critical nature of the regulation/sensing line. It doesn't make sense that that essential step was overlooked. I am also a fan of K.I.S.S. and a PRV System is simple and does the job. But given the climate for business, specifically in the energy sector; to reduce it's carbon foot-print. I would wager that there is an absolute aversion to allowing potentially millions of cubic feet of methane to be released into the atmosphere. A monitor system curtails that but also poses a higher risk. This should be an opportunity to educate the public and the industry itself, on the challenges of unintended consequences. Again not wanting to rush tom blame, but at first glance this appears to be an issue of possible mechanical failure compounded by human error.
The gas system in Michigan where I am has an in house simple mechanical regulator ahead of the gas meter that takes the house line feed pressure from around three psi to .5 psi. I don't know what pressures are farther back in the system. But feeding a bunch of customers at .5 psi with some kind of a high flow low pressure electrical mechanical regulator is asking for problems.
Larry Medler a lot of OLD systems (1800s) can’t handle anything higher than 0.5. Hence why they were replacing that line and adding regulators on houses. In2015 the federal government said they have to update their entire system by 2035
Devin, I appreciate your input... I did a two hour video on this plus two other videos... I even posted a video that it WAS the regulator BEFORE the NTSB did their release! I did that video 8 hours before them! ua-cam.com/video/_4OqdkmxcEw/v-deo.html
Yeah. They take 1.5 PSI gas from the mains, ad bring it down to 0.25 PSI for use within the house. When confronted with 75PSI of gas, They could not function properly. I bet we will find that the houses that exploded and caught fire had the oldest pressure regulators, along with old pilot lights.
Robert Szasz some older systems don’t have regulators on the houses. Just the main regulators. They have been adding house regulators to houses during this main replacement project
NTSB I would like to know why, when a UA-camr, actively involved in creating videos is hit by a high speed Amtrak train, yet not a word is said about it or the circumstances?
G'day, Methinks that whomsoever capped-off that old length of Cast-Iron Pipeline, without first thunkin' to relocate the Pressure-Regulator's Downstream Data-Sensor into the shiny bright new high-tech Plastic Pipeline - which was actually carrying the Gas & connected to the Customers' Households...; that there individual is goanna find themself to be at the unrelenting focus of lifetime's worth of punitive Paperwork, as Pennance. Alliterative Agony awaits (!). Such is Life... Have a good one, ;-p Ciao !
+America. Archived. In a Culture ever-hungry for blameworthy Villains, or at least a functional Scapegoat who might immediately suffice ; they'll probably be lucky not to be lynched, or at least tarred & feathered for Professional Negligence causing Death (somebody was killed by the fall of an exploding Chimney, apparently...). And, just quietly, if the individual concerned was a Migrant (lawful or otherwise), or any kind of a Moslem ; then they certainly should not expect the Enquiry-process to be particularly gentle nor friendly..., and if their wife wears a Hijab then they may well wind up in "Gitmo" ! Tronald Dump's (Mal)Administration would dearly love somebody to demonise, as a distraction, at the moment... Such is Life, Have a good one... ;-p Ciao !
+Schlomo Weissbergman-Goldsteinwitz, Ph.D. G'day there, Herr Doktor, And, in which field o' study did ye obtain y'r Doktorate of Phoolosopholly, then...; Athletics, perhaps, to take advantage o' y'r oblivious talent fr runnin' clear out o' evidence, and leapin' t' unfounded conclusions...? "Baby Boomers" y'see are, by definition, they who were born in the decade (10 years) following the conclusion of WW-2, in theory unto Parents who had put off concieving a Rug-Rat of their own until Hostilities had Bin-Terminated. So, technically, one had to be born between January 1946 (Hitler shot himself in May of '45) and May of 1956 (Japan surrendered in August 1945) to be in the bracket of "9 months & 10 years following VE & VJ Days"...; however for most purposes, the common "definition" of a "Baby Boomer" is anybody who was born between 1945 & 1955...., whose parents were either Military Veterans - or were of an age to have orchestrated their fertility to take account of the War having been happening when it did. How, or what, "Baby Boomers on the Internoodle" might possibly have to do with this Comment-Thread, or this Video ; is a matter which only your own fevered imaginitis might be in a position to guess at....(?). In case ye thunked that ye was referrin' to m'self then y'd be sadly mistaken, my father bein' born in 1909, he was too old for fightin' in WW-2 (and he was in a reserved occupation anyway...) whereas my mother was born in 1936 and was only 9 years old when Nagasaki was Atom-Bombed ; as for myself - I wasn't born till 1961, so I'm more of an "ICBM/Space Race/Cold War Baby" than any kind of "Baby Boomer". It be not often that I get a chance to plead being too young to be guilty as charged ; but there ye go, and now ye know and (perhaps) ye stand corrected (?). Just(ifiably ?) sayin' Take it easy, ;-p Ciao !
I still think pressure relief valves (which are different devices than pressure regulators) would have prevented the fires/explosions and downstream appliance/equipment damage.
Robert Szasz not to mention over time, set-points on relief valves tend to drift and require periodic rebuilding, especially after a relief valve lift event.
rwbishop house regulators have emergency vent off valves. However most of these houses didn’t have regulators. And most house regulators are only rated to 50psi. So any higher will cause failure and leaks
What's not mentioned is the age of the presumably outdated and outmoded cast-iron piping, presumably from the initial installation. The code being 100 years old or thereabouts is already mentioned. This is an area with extreme seasonal temperature differences and over time, that aging metal piping was undergoing a gradual metal fatigue. Posters below mention, if extrapolated, the main lines from the utility pushing the flamable, combustible natural gas along at 75 PSI until it hits stepdowns at the regulators to 1.5 PSI after the regulator, and reducing further to .25 PSI on entry into the homes and their appliances. So there is the temperature change factor and the huge PSI differentials along with the aging of several critical parts that were pretty much installed and forgotten about until someone got the bright idea of upgrading the piping and so they did exactly what they were told or paid/.contracted to do and so this is easily seen as "accidents waiting for a place to happen." Alongside the obvious need for more timely updating of the components, wouldn't it be wise to do the work in the warm months, where the gas could be shut off with minimal discomfort and inconvenience to the customers and change out the piping along with the outdated meters and regulators, and/or add said meters and/or regulators to update the entire fuel delivery system to customers in a smaller "block" of homes until the project was completed, along with documenting everything that was completed along the way (as well as which homes were awaiting these service updates)? It all looks so slipshod to me and all that considered it's amazing that explosions did not happen much sooner. Based on the comments of the NTSB it seems they need their department expanded. I fear there are more disasters or "accidents" than they can keep up with, hence the public waiting much longer for their findings, recommendations and the implementation of these recommendations.
FYI. To those who thing regulators on appliances would stop explosions , the fuel lines will leak at 70 psi because they were only designed for 0.25 PSI. Over pressurizing causes leaks on gas pipe.
Appliance regulators wouldn't be as good as one at the point of entry, but the lines inside the house are probably ok to 100+psi
Robert Szasz nope.
@@BustedWalletGarage ok, well then the rest of the country is sort of boned. Pretty sure to code gas line in California would take it. Certainly the line running to the houses.
@@BustedWalletGarage would there be leaks or catastrophic failure. Because... I mean.. it's iron pipe mostly, right?
Robert Szasz nope. I’ve got a gas contractor license. Gas pipe code was mostly written over 100 years ago. Typical house gas pipe leaks at 35 psi.
So the pressure sensor for the regulator was connected to a gas line which was then capped, and drained of all natural gas.
The regulator, seeing the low pressure from the sensor as the capped pipe was depressurized, started to open to boost pressure in the system...
Since the sensor wasn't connected to the system at all anymore, it just kept on opening until it was pushing 75PSI of gas into a system meant for 1.5 PSI...
SlocketSeven 0.5psi*
I'm a natural gas design engineer and project Mgr., regulator inspector, distribution company, very familiar with these types of systems. And ready to retire. I've seen a lot over the past 50 years, but there are still a few things I don't quite understand about this incident. First, almost without exception, any given regulator's sensing lines (in this type of installment) terminate at a certain number of pipe diameters downstream of the regulator; often this distance downstream is only inches away, sometimes several yards or more. Are the authorities saying that a new length of pipe was installed at the station outlet, near the outlet block valve (outlet shut-off valve), and that the sensing lines were never considered as germane to the system's operations? If that's the case, this was a fail of epic proportions. I've never met a regulator technician who didn't appreciate the critical nature of this circumstance. It is, in my experience, always topmost in the minds of operations technicians and station engineers. Further, for the new tie-in to be made, one presumes that the station valves would have been shut off and later re-opened. In my neck of the woods this is always done by a qualified regulator technician. What happened? This boggles the mind. I can't accept that we know all of the facts on this, but if we do, and this is how it came to be, then someone was asleep on the job.
As to PRVs (pressure relief valves), don't be fooled: they are the only known means available to act as a fail-safe for a system, despite their annoyances. It is rare for a PRV to "catch fire" upon the release of gas, and even if one did, it would, if properly engineered, serve as a flare until someone could shut down the system. Yes, there is always a risk, but it's an absolute certainty that without a PRV system in place then accidents like the one in Massachusetts will happen, and who wants that.
For LP systems, my favorite, tried and true PRV is what we used to call an "oil seal." I love them. I would recommend to Congress that all LP systems have these in place, and that they require annual inspections and maintenance. These have ZERO mechanical parts. They let the laws of physics do the heavy lifting. They're cheap to build and install, can be done through a vendor or in-house, and could save a system like the one at Lawrence. It's a damn shame they didn't have some PRV system in place; their Monitor-Control systems are good for keeping steady pressures without losing a system to troubles on the station inlet side of things, but once pressure enters the line for whatever reason, as it did here, only a PRV will give the gas company some control of the escaping gas. Why leave it to chance?
I'm an engineer in the industry too and I agree with your thoughts. But also, what about the monitor reg? A single regulator is not an adequate means to manage pressure.
I am not sure if it is clear from the press conference (given that it was geared towards layman's terms and light on configuration/operational details) if there was an operating regulator monitoring system in place. I've worked around hundreds of monitor regulator systems and can attest to their overall reliability as an over-pressure option...IF they are well-maintained. I agree, without wanting to rush to blame; that a regulator field technician would/should have been involved in the return to service and thus have a situational awareness of the critical nature of the regulation/sensing line. It doesn't make sense that that essential step was overlooked. I am also a fan of K.I.S.S. and a PRV System is simple and does the job. But given the climate for business, specifically in the energy sector; to reduce it's carbon foot-print. I would wager that there is an absolute aversion to allowing potentially millions of cubic feet of methane to be released into the atmosphere. A monitor system curtails that but also poses a higher risk. This should be an opportunity to educate the public and the industry itself, on the challenges of unintended consequences. Again not wanting to rush tom blame, but at first glance this appears to be an issue of possible mechanical failure compounded by human error.
Gregory, would you please contact me? WilliamAHuston(at)gmail(dot)com Thank you!
The gas system in Michigan where I am has an in house simple mechanical regulator ahead of the gas meter that takes the house line feed pressure from around three psi to .5 psi. I don't know what pressures are farther back in the system. But feeding a bunch of customers at .5 psi with some kind of a high flow low pressure electrical mechanical regulator is asking for problems.
Larry Medler a lot of OLD systems (1800s) can’t handle anything higher than 0.5.
Hence why they were replacing that line and adding regulators on houses.
In2015 the federal government said they have to update their entire system by 2035
HOW MANY FLOW METERS WERE ON THE PIPE? WAS THE METER, WORKING OR NOT?
Construction Engineering & Photography most systems only have one main meter for the whole system. And should have had an alarm
Devin, I appreciate your input... I did a two hour video on this plus two other videos... I even posted a video that it WAS the regulator BEFORE the NTSB did their release!
I did that video 8 hours before them!
ua-cam.com/video/_4OqdkmxcEw/v-deo.html
Aren't there regulators, meters, and shutoffs at each residence? Did those regulators have to fail as well?
Yeah. They take 1.5 PSI gas from the mains, ad bring it down to 0.25 PSI for use within the house.
When confronted with 75PSI of gas, They could not function properly.
I bet we will find that the houses that exploded and caught fire had the oldest pressure regulators, along with old pilot lights.
Robert Szasz some older systems don’t have regulators on the houses. Just the main regulators. They have been adding house regulators to houses during this main replacement project
Robert Szasz most house regulators are only rated to 50psi. After that they vent out the extra gas and fail. Causing gas leaks
@@devinbender8428 thanks for the reply. I would be surprised if the regulators vented at 75psi (I think the rating is for rated delivery, not failure)
Robert Szasz no the delivery rating is completely different.
Input rating 40psi
Output depends on the spring setting
Usually 0.25psi, 2psi or 5psi.
NTSB I would like to know why, when a UA-camr, actively involved in creating videos is hit by a high speed Amtrak train, yet not a word is said about it or the circumstances?
HappyQuails they dont investigate dumb asses walking on the tracks
Ok, HappyQuails...so what happened and what were the circumstances?
G'day,
Methinks that whomsoever capped-off that old length of Cast-Iron Pipeline, without first thunkin' to relocate the Pressure-Regulator's Downstream Data-Sensor into the shiny bright new high-tech Plastic Pipeline - which was actually carrying the Gas & connected to the Customers' Households...; that there individual is goanna find themself to be at the unrelenting focus of lifetime's worth of punitive Paperwork, as Pennance.
Alliterative Agony awaits (!).
Such is Life...
Have a good one,
;-p
Ciao !
+America. Archived.
In a Culture ever-hungry for blameworthy Villains, or at least a functional Scapegoat who might immediately suffice ; they'll probably be lucky not to be lynched, or at least tarred & feathered for Professional Negligence causing Death (somebody was killed by the fall of an exploding Chimney, apparently...).
And, just quietly, if the individual concerned was a Migrant (lawful or otherwise), or any kind of a Moslem ; then they certainly should not expect the Enquiry-process to be particularly gentle nor friendly..., and if their wife wears a Hijab then they may well wind up in "Gitmo" !
Tronald Dump's (Mal)Administration would dearly love somebody to demonise, as a distraction, at the moment...
Such is Life,
Have a good one...
;-p
Ciao !
Whoever the “inspector” or “supervisor” of the project should have monitored pressure. They will be under investigation for sure
Baby boomer liberals should not have access to the internet.
+Schlomo Weissbergman-Goldsteinwitz, Ph.D.
G'day there, Herr Doktor,
And, in which field o' study did ye obtain y'r Doktorate of Phoolosopholly, then...; Athletics, perhaps, to take advantage o' y'r oblivious talent fr runnin' clear out o' evidence, and leapin' t' unfounded conclusions...?
"Baby Boomers" y'see are, by definition, they who were born in the decade (10 years) following the conclusion of WW-2, in theory unto Parents who had put off concieving a Rug-Rat of their own until Hostilities had Bin-Terminated.
So, technically, one had to be born between January 1946 (Hitler shot himself in May of '45) and May of 1956 (Japan surrendered in August 1945) to be in the bracket of "9 months & 10 years following VE & VJ Days"...; however for most purposes, the common "definition" of a "Baby Boomer" is anybody who was born between 1945 & 1955...., whose parents were either Military Veterans - or were of an age to have orchestrated their fertility to take account of the War having been happening when it did.
How, or what, "Baby Boomers on the Internoodle" might possibly have to do with this Comment-Thread, or this Video ; is a matter which only your own fevered imaginitis might be in a position to guess at....(?).
In case ye thunked that ye was referrin' to m'self then y'd be sadly mistaken, my father bein' born in 1909, he was too old for fightin' in WW-2 (and he was in a reserved occupation anyway...) whereas my mother was born in 1936 and was only 9 years old when Nagasaki was Atom-Bombed ; as for myself - I wasn't born till 1961, so I'm more of an "ICBM/Space Race/Cold War Baby" than any kind of "Baby Boomer".
It be not often that I get a chance to plead being too young to be guilty as charged ; but there ye go, and now ye know and (perhaps) ye stand corrected (?).
Just(ifiably ?) sayin'
Take it easy,
;-p
Ciao !
I still think pressure relief valves (which are different devices than pressure regulators) would have prevented the fires/explosions and downstream appliance/equipment damage.
A pressure relief valve would have to vent somewhere. Wherever it vented to would be an explosion and fire risk
Robert Szasz not to mention over time, set-points on relief valves tend to drift and require periodic rebuilding, especially after a relief valve lift event.
rwbishop house regulators have emergency vent off valves. However most of these houses didn’t have regulators.
And most house regulators are only rated to 50psi. So any higher will cause failure and leaks