I guess I didnt miss much from being banned then. The OP never came back to tell us if he got evicted and no one was killed in the blast. Well almost.
But I was going to add before I was so rudely interupted was on 12th November seven days after Bonfire night an inquest concluded on a 67 year old woman who called an ambulace suffering what was thought to be covid virus and being given oxygen by the Paramedics in her house while sitting on her chair began emiting sparks.
The two paramedics together with her husband and grandaughter escaped while she died still sitting in the chair.
It was a small bottle of portable oxygen known to those in the industry to be a cause of concern, but I am unable to give further information as to the origin of said apperatus for fear its overseas origin may be construded as a racist comment.
However the photos below of the resultant fire and destruction of property from such a small oxygen cylinder may also cause a slight concern to the Op's Insurance company and his fellow residents at his flat.
https://www.expressandstar.com/news/...use-explosion/
Nah it was pretty much spot on topic, oxygen cylinder, open valve, sparks fire and death.
At least she wasnt blending in the place so I guess the insurance will cover.
Here is another today described as a "gas explosion" but you will note no burn marks, no scorch marks, just a passive pressure blast from the inside of the house to out. Now unless North Sea Gas to houses in Linconshire come into the building at 3000 psi (207 Bar) or they are pumping hydrogen down the pipes
That's a pretty clean "explosion" what with no fire, no burn marks and half the house halfway across next door.
Maybe the OP Mixing "J's" on Elm Street.
https://www.bbc.co.uk/news/uk-englan...shire-55279445
Used to require a 16:1 ratio (from memory) before you get such a result
Last edited by iain/hsm; 13-12-2020 at 04:15 PM.
Odd there was no fire. Definite large overpressure; if gas were involved, you'd think there would be enough energy for a spark to ignite it.
The fire was proberbly contained inside and around the gas oven at the back of the house a Methane/Air explosion with total combustion resulting in the resultant overpressure air blast from the ensuing shock wave that blows the doors off so to speak. Combustion very small pressure blast much larger. I was reading a typical nuclear blast yield from a modern dial down weapon creates only around 30 psi The pressure wave however is enormous. 30 pounds per square inch over a mile wide area could make a mess of your garden plantings. The photo is great showing the effect of a pressure blast wall
There is another good method example called MUCTA (Methane-Oxygen Unconfined Combustion/Explosion Test Apparatus)
Not sure if we can talk about it on an open forum for fear the woke get upset but its pretty interesting.
Use the same principle calculation for that "fertiliser" and fireworks explosion at the Beirut docks, 2700 tons of fertiiser off some Russian cargo ship and a bunch of "fireworks" next door. Kill 100 folk and make 300,000 homes rubble and call it a fertiliser explosion blasting off a big red/brown clould. Nope no such way.
Last edited by iain/hsm; 13-12-2020 at 07:16 PM.
One of my Uni lectures many years ago covered explosions of combustible materials. It is possible for the exposion itself to blow out the combustion so that no fire is observed. You need a lot of oxygen for combustion and an explosion can remove much of this. A very complex relationship.
This is also why hydroxy breathing mixes for very deep diving are possible. Logic would say mixing hydrogen and oxygen would be exceedibgly dangerous but the percentage of oxygen is so low that it is not an explosive mixture.
Heck Allan your showing your age on that Hydrox subject. I dont think many forum members were around on the 4th May 1985 at Boulevard De L'Océan outside Marseille let alone wondering if compressing the breathing gas for the bottom mix with its Hydrogen cyanide maximum concentration of 0.4 ppm and the Phosphuretted Hydrogen content of 0.012 ppm together with the Arseniuretted Hydrogen max 0.002 ppm was OK breathing it at 450MSW depth. Let alone if you would blow the place up.
But Hydrogen is still doable for a shallow sport diving depth range if anyone is interested.
By contrast a 450 MSW dive profile would run hydrogen at 55% with a PH2 of 25.5 bar on a 55/44/1 mixture (at 450MSW)
But your dive profile may tax the computive power of your ACE Profile/ Deco Planner
1. 2 days at 10MSW on Heliox 80/20
2. Compress down from 10 MSW to 450 MSW in 38 hours in helium to 200MSW then hydrogen for the balance blow down
3. Bottom time 63 hours at 450MSW on 56% Hydrogen and 0.9% Oxygen with the balance helium (mean average PH2 of 25.8 bar, mean P02 of 0.4 bar
4. Eight (8) hours in a mixture of 30% H2, 0.9% 02 and helium (mean PH2 13.8 bar)
5. and 172 hours in Heliox (0.9% 02) of which 54 hours at more than 450 MSW
Decompression at 1.33M/hr or 45mins/m as its easier from 450MSW to 15MSW
Then at 1m/hr from 15MSW to the surface (not forgetting to increase the oxygen)
The p02 increasing from 0.6 bar from 450MSW up to 350MSW
Then at 0.5 bar up to 120MSW
Then upped to 0.6 bar P02 up to 15MSW
To finally a 24% oxygen percentage
Total decompression time 14 days 5 hours and 15 minutes
And that was the simplest profile it gets worse
Last edited by iain/hsm; 13-12-2020 at 10:12 PM. Reason: spelling
Shit. Disliked in error. Meant to like. Sorry
Remember anything you read on the internet was probably written by some guy sitting at home in his underpants! Including this !!
Illegitimi non carborundum
According to the gas industry, most houses that are destroyed by a gas explosion are because the resident is nicking the gas by bypassing the meter(s).
Badly bypassed electricity meters can give sparks and badly bypassed gas meters the gas = boom.