Not even, a tiny bit more metal on that float plug thingamajig and this never would have happened. It probably would have costed literally nothing for that extra tiny bit of metal so it wouldn't misalign.
My Father was killed when I was 2 years old. Practices of the construction site called for storing an oxy-acetylene welding rig inside an air tight shipping container. One morning the workers went inside the shipping container, one saying they smelled gas. One man pulled the pull switch on the metal housed lighting assembly. This caused the arch which ignited the flammable vapors that had filled the container over a period of 16 hours. My Father was hit with the shipping container door, he died in between heart beats. Do you realize how fast that had to happen? It was a detonation, no fire, just a huge pressure wave bouncing against the walls of the container, obliterating it and the workers around. I’m an Occupational Safety, Health and Environment major at the University my Father lost his life at, building a building I walk past everyday. I want every parent to go home to their children. I plan to use my story to break the stigma of doing a job how we’ve always done it or do it no matter the safety issues.
It's odd there is only one check valve. Heck, here in Idaho, sprinkler systems for your yard are required to have a double check valve. The point to a double check is to create redundancy if one fails. Also, I would install and outdoor anti-siphon ventilator before the shed, should both check valves fail, it will all vent outside or up a long thin chimney. Total cost of modifications? $300.00 for all parts and time. I generally believe that you don't install a venting device for any flammable gas inside a room. The heater is a no factor with my setup. You can do a double anti-siphon for redundancy. All proper anti-siphon and check valves have simple test ports to ensure functionality which should be done monthly in this application. it takes about 10 minutes to test all vales.
I hope the company sued the check valve manufacturer. The purpose of safety equipment is to guard against human error. While the crew may have made a mistake in delaying to start the generator, the check valve SHOULD HAVE saved them.
My dad worked at an acetylene plant in the mid 70s, said it made him really nervous and he was the only guy who would cross the road to smoke a cigarette, quit after a few weeks and not long after the place blew up. this was in Alberta Canada.
There's definitely some sketchy stuff going on in industrial jobs here long hours also. A job I left recently a coworker drove under the boom of a power line truck when a guy was in the basket hitting the side of his truck. Boss would get us working long hours. 6:30 am off at 12pm back to work for 5pm and back home at 4-5 in the morning
Luckily it wasn't like the oilfield work I did, 6:30 am till whenever, usually 6-8 pm and late night calls to clean spills, then back to work. I've worked under slept for so many days it wasn't funny.
Mr Grant Johnston:. I agree with u. What are these qualified, engineers with degrees supposedly...doing putting a PROPANE HEATER (Flames) in a closed in space making FLAMMABLE I said FLAMMABLE gas. Uh uh I dunno. I guess when u have a degree u can do stupid things and no one is allowed to question ur actions????
@@Voliere-infoNl yeah but they are not used in what would be considered an explosive atmosphere, or they are closed off from surrounding atmosphere. I’ll bet you this room was considered an explosive atmosphere due to the tanks and pumps having a possible emission of gas. Whoever put that heater in there WAS stupid, and they contributed to the explosion.
In our industry we never rely on a check valve in a safety-critical application. Instead use a definite on/off control valve, either manual or automatic. At the very minimum use 2 in-series check valves. Or even a "block and bleed" arrangement of valves that do not allow hazardous fluid to contact non-hazardous fluid that is separated by the valving. Core message....never depend on a single check valve for safety, only for non-hazardous process conditions.
Well a liquid check valve is definitely not to be used as a gas valve! And they corrode for a past time when used with domestic water, even if they’re bronze etc, the water scale built up stops the seat from sealing in a reverse flow situation. I deduced this by simply being a human
@@TheWilferch Honestly, Im not in industry so that being said. Im amazed at some of the causes for these incidents. Dust in the rafters. If you don't know what blows up and what doesn't. Your in the wrong job. Money is not the only issue. People died, at work, horrible deaths.
@@jeromeduffy9270 .... re-reading your note addressed to me I have no idea what you are saying. No doubt people died a horrible death and in many cases this can be avoided when industry best practices are employed....both by design and by operation. But it needs to be supported at all levels of the organization including ther CXO suite...so as not to only give "lip service" to the issues. It ends up being a corporate "culture" issue of why things happen. Why am I supposedly in the wrong industry if I have a sense of what constitutes proper plant design and operational -procedures based on education and experience? I see too much of this in various industries, because the "focus" and the knowledge of hazards and risks are not being properly recognized, and too often the lack of "operational-discipline" or not recognizing all the pertinant factors ( lack of a HAZOP study of the design)...are to blame.
Especially since backflow preventers come in all shapes and sizes for every purpose. Truly unbelievable how a company can have so few precautions for something so critical.
I worked at this plant for 15 yrs. and there was to many violations at this location The perth amboy code enforcement and osha was the atleast 3 time a month until it blue up and killed 3 of my best friends.
Damn you guys have been on RU-vid for 11 years? So since 2007, I don't even think google owned it at that point. You guys were some of the original people on RU-vid lol
@@philldill3117 Personally, I'm glad. RU-vid is fairly well accessible, and reports like these are informative and transparent. Mad props to the USCSB for utilizing new tech way ahead of other government agencies.
@@hauntedshadowslegacy2826IIRC, the Queen had a similar penchant for adopting new tech early: she had her own personal RU-vid account and was one of the first world leaders to have social media accounts. (If not the first!)
Acetylene has been used for well over a century and its hazards are very, very, VERY well known. That's why acetylene generators for home lighting use were normally built WELL away from the house. ASCO is a very old company who should have known to have more than one safety, perhaps a redundant check valve. Water doesn't care about more check valves. Rexarc is a very old company too, formerly Rego. They should have sought continuous process improvement as noted. Old companies where processes never change are ripe for disasters. Using an open element heater in an acetylene plant is profoundly fucking stupid. Liquid-filled space heaters are also a very old design which they should have used instead. For that matter any electrical connections and wiring should have been in explosion-proof conduit and with switched boxes so any outlets would be electrically dead before connection/disconnection. It's not fucking rocket surgery!
Ob fuscated....correct pretty much on all points. Sealed conduit for all electirical runs, never ever an open element heater ANYWHERE on such property.
If, that is a correct representation of that ( check valve, ) Whoever designed that thing was an idiot, not an engineer... It should have had a much longer ( guide rod ) at the bottom and the rod should have been guided with a pair of centering rings in the center of the pipe to prevent the possibility of jamming in the housing and preventing the check valve from doing what it was supposed to do .....
Are you kidding me? I had a hose pipe fitted to my house, just a regular hose pipe, and that has to have a DOUBLE check value. You can really have something this dangerous with just a single check valve?
Acetylene is a very unstable molecule, to the extent that it will even blow up if it goes much over 15 psi (even without oxygen). So it has to slowly be absorbed in a solution in the tanks filled with Acetone. Like the way carbon dioxide is absorbed by water in a soda can. It's so dangerous I just try to do as much as I can with propane instead, for metal cutting.
Absolutely. I stopped using acetylene years ago. I don't do carburising or artisan welding so all it's for is severance cutting and propane works perfectly for that.
Doing HVAC, I remember in 2015 when a plant in China that distributed calcium carbide exploded. Acetylene prices went up that year and still haven't come down.
My guess is the operators were doing the startup and they either a) got told to shovel snow or b) got distracted clearing snow to the shed when they headed out to the recycle tanks to complete the switchover.
If you have the chance of gas entrained in liquid then why not use a phase separator to shunt the gas to a stack while liquid continues in the liquid line? Granted there would be a pressure differential between the liquid and the gas that might need a pump to assist. Seems super simple and you wouldn't be betting your life on a single check valve.
Jeez that's tragic - I'm surprised it wasn't advocated for there to be redundancy in the check valve - but I'm unfamiliar with the engineering specs on check valves so there may be very good reason why this wasn't recommended.
That would be more dangerous. That would, in the same failure condition, cause acetylene to be released in the factory building, potentially killing more people than when it got released in the shed. OTOH it could be argued that it would be "safer" since there is guranteed no ignition sources inside a acetylene factory due to Ex classification, but better be safe than sorry. And gas is invisible to the eye, so you wouldn't see a leaking check valve in the same way you would see in a RPZ Backflow preventer in a water vs water situation (where both supply and consumer side is water-based). (In this case, the consumer side is gas-based). The best protection here would be a water trap with a float valve, whose spring is stronger than the safety valve rupture pressure (at which gas pressure the safety valve of the acetylene generator would rupture). This float valve should close the inlet pipe if the water level becomes too low. The inlet pipe, should be as long so it reaches into the water trap sufficently deep, so even the lowest allowable water level would still have the inlet pipe deep enoug so gas pressure can't get through. In normal condition, the water trap would be filled enough so the float valve is open. If the supply pressure becomes too low, gas presses on the water surface, causing the water surface level in the water trap to drop. This would close the float valve, such as any gas pressure cannot force it open ( the safety valve would rupture first, which would propably sound alarms, evacuate the building and also be telltake signs that something is wrong ). By having spring pressure strong enough, it also is good safety against the valve failing. Note that we are talking about a float valve, which arent reliant on the water or gas pressure to remain functional. The maximum spring pressure allowable in a float valve, is the lift force of the float, which is dependant on its displaced water weight, which means the supply water pressure doesn't need to be higher than the float valve spring pressure.
@@frankherrick1892 As I said, a water trap with a float valve that forcibly closes the inlet if the water level becomes too low. This then becomes an inline phase separator with a safety. Since the opening force of a float is directly equal to the weight of the water it displaces, and is not dependant of water pressure, instead its the level of water in the phase separator that controls it, a float valve can be made much stronger than a check valve, without an need to increase water pressure. The problem with the RPZ backflow preventer is that it would release acetylene through its discharge port at a failure condition. A double checkvalve (ergo a RPZ without discharge port) could be a solution, but then you don't get any early warning if one of the checks fails and the problem could go undetected for a long time. A second solution might be a RPZ backflow preventer, but screwing a pressure sensor into its discharge port, connected to an alarm. If the RPZ backflow preventer fails in such a way it would release gas through its discharge port (for example if one of the checks fails), it instead triggers an alarm. That gives kind of a double safety, but still could be provided fatal if the sensor first fails, and then one of the checks. Designing a completely safe system , especially for explosive gas like acetylene, is very difficult.
You are right. Backflow preventers are standard in domestic and industrial water systems to prevent polluting potable water. They are cheap and readily available and every plumber is familiar with them!
There was a pump but its suction was open to the atmosphere and it pumps only liquids, not air. Under the pressure acetylene is made at, gravity feed would be pretty much impossible.
Heck, even if I was one of them I could easily see myself lighting the cigar too. Even with prior knowledge of the place that it's oilfield. Especially when hangin' out with friends you can just forget about it. Humans are creature susceptible to distraction. I watch a lot of videos from this channel, mostly just for fun, though. You guys are doing a Great Job, fine interesting documentries, in-depth analysis while possibly saving a lot of lives at the same time. Thank you so much for these videos!
It was likely a combination of flying debris, the shockwave, and the heat/flame. As for fault, cases like this are measured in percentages in the U.S.. I'd personally place 40% on the valve company, 58% on the acetylene plant managers (because it was up to them to order a replacement valve), and 2% on the workers for delaying the water in the first place. I don't know exactly how it went in court/arbitration, but that's how I view it.
Maybe this is just being overly simplistic, but why don't these pipes have more than one check valve in series (spaced a moderate distance apart so it's unlikely they won't both get physically damaged from a single event, like being whacked with a steel girder, and possibly of different designs to mitigate systemic failure modes) so if one doesn't work as intended, the second one acts as a backup since both of them failing simultaneously is far more unlikely?
No laughing matter in this situation, acetylene should have been venting to a safer location, maybe the space heater was what caused the 💥 explosion. This one was especially dangerous, the valve should have been left shut but it was opened to protect it from freezing. The check valve was possibly old and faulty.
You mean the SL-1 reactor? That's more in the realm of radiation rather than chemicals. Good news, though- the NRC (Nuclear Regulatory Commission) has a channel on RU-vid as well! If you're interested, it's NRCgov.
Can you imagine what Sheldon Smith would have to say about this investigation, he would have been straight to the point as the csb should always be, well done.
