A little torch incident that could have been a lot worse

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This should probably be posted in the safety forum but I thought more people would see it here.Yesterday I was working on the tail gate hinges on my friend Chip's dump truck. I knew I was going to need a set of torches to do the work, I told Chip that I had one empty bottle of acetylene and the other was just about empty and we would need to get them filled before we could do anything. He said that he has a set of torches and both of his bottles were full. He brought them over and set up the torches, I climbed up into the bed of the dump truck and started to do some grinding on an area to be repaired while Chip was going to cut some patch repair panels for me. I'm not exactly sure what had happened next but I became a real believer in flash back arresters right quick.I didn't see exactly what had happened but saw Chip drop the torch head and suddenly I saw a flame shooting from the Oxygen hose, about three or four feet down the line from the torch head. Chip was kinda trying to kick the torches away from the back of the truck, I jumped down from the back of the truck and ran to the bottles and shut them off in a hurry. I didn't think my fat a$s could move that quick anymore, but it did. I guess seeing flames shooting about four feet out of the hoses while it was slinging around the ground like a snake trying to strike will make anyone move quickly.After my butt checks finally began to unclench and everything settled down for a few minutes I asked him what had exactly had happened. He said that he first cracked the oxygen valve and then open the acetylene valve, struck the striker and the torch fired, popped and went out. He said he then shut the valves back off and repeated the process, only the torch was acting as if it was not getting oxygen, just the orange sooty flame from the acetylene. He said he shut of the acetylene valve again and the torch started vibrating and the next thing he new the oxygen hose burst and erupted in flames. This could have gotten real ugly in a hurry had I not shut the bottles down as quickly as I did. I would not be making this post had we used my torches with flash arresters on them. This is post is more to let the new guys know to NOT take cutting torches lightly, they can be a very useful item, but when not handled correctly things can go bad in a hurry. There has been a lot of discussion on here about proper handling of torches, using the proper safety devices that are available and also about paying attention to your surroundings and others. Had I payed attention and noticed his torches did not have any flash arrestors on them I would have insisted on using my regulators, hoses, and torch head and this never would have happened. When all is said and done the only real damage was to the torch hoses, an extension cord, a cord to the grinder, a pair of soiled boxers and to the torch head itself. The torch will have to be sent off and rebuilt before being used again as I'm sure some damage was done internally to it and should not be used until it has been checked out by a qualified repair center. Attached ImagesI am what I am, Deal with it!If necessity is the Mother of Invention, I must be the Father of Desperation!
Reply:DANG!! scary. something must have been clogged??
Reply:Good post. It got me thinking about how I do some things. Usually at the house, I leave the tanks strapped up inside the garage and just pay out enough hose to do the few quick cuts in the drive I need to do. Most times I pull the door down so I'll keep any stray sparks from getting into the over filled garage. My 1st thought was what that 4' of flame writhing around would have done if the door had been up. The old car in there with the gas tank right by the door, the misc leaves that always seem to blow in no matter how often I try and clean it out, the gas cans for the blower, mower etc near the door and what a mess that could have been. My next thought was what IF the door had been closed! It's a PITA to get that double door open some times, and I'll bet right then I would not have been in the mood to futz with being sure that door goes straight up evenly, not to mention that the flames would most likely have been between me and the cylinders, both fire extingushers and so on.Time to quit being lazy, and just wheel the tanks out when I need to cut. They're already on a cart, so it's not that big a deal. I know the rosebud has flash arrestors, I'll have to double check the cutting torch..No government ever voluntarily reduces itself in size. Government programs, once launched, never disappear. Actually, a government bureau is the nearest thing to eternal life we'll ever see on this earth! Ronald Reagan
Reply:When I bought my torch the dealer told me I didn't need flash arrestors as they were built into the torch itself.I bought em anyways and installed them. I figure I can't go wrong. My reel has a quick connect on it so if I plug in a different torch without an arrestor I am still protected. You never know.....Thanks for the post!Lincoln Power Mig 210MP MIGLincoln Power Mig 350MP - MIG and Push-PullLincoln TIG 300-300Lincoln Hobby-Weld 110v  Thanks JLAMESCK TIG TORCH, gas diffuser, pyrex cupThermal Dynamics Cutmaster 101My brain
Reply:Good story dabar. Glad no one got injured, it could have been a real disaster. And your right about posting it where you did as a warning to newbes."SOUTHPAW" A wise person learns from another persons mistakes;A smart person learns from their own mistakes;But, a stupid person.............never learns.
Reply:I've had similar experiences with oxy/acetylene. Crimping the hoses between the bottles and burst point will extinguish the fire usually, while dealing with tank valves or as DSW pointed out, a stuck or hard to open door. if the flame doesn't completely extinguish, at least the pressure is reduced and the hoses aren't lashing around. I use flash arrestors, but at the regulators only. My torches don't have the built in arrestors and I've never added them, maybe it's time I did! Thanks for posting this.Only when the last tree has died and the last river has been poisoned and the last fish has been caught will we realize we cannot eat money.                                         -Cree Indian ProverbSA 200 LincolnVictor Torches
Reply:Glad nobody was hurt..Good to show people that are starting out how dangerous it can be.I always treat my O/A setup with the utmost restpect everytime i use it.
Reply:Damn Dave!  You almost burned yourself up. I'de expect flames to shoot out of your cheeks from eating lots of Taco Bell, but this is nuts!!!  could have looked like this: Attached Images
Reply:Originally Posted by BurningMetalDamn Dave!  You almost burned yourself up. I'de expect flames to shoot out of your cheeks from eating lots of Taco Bell, but this is nuts!!!  could have looked like this:
Reply:I have a Taco Bell on the corner (about 300 foot from my house on the other side of the street) and just out of habit from hearing (several hundred times a day) "Welcome to Taco Bell, May I take your order please?" I have actually answered my phone saying it.HAHAHA. dabar39, I am glad no one was hurt, and after reading your post and this thread I went to check my lines in the shop and on the truck and I do have spark arrestors. Makes one think thats for sure, I knew I had them but with other people using my stuff you never know what changes. Thanks a lot for this reminder.
Reply:Although I run arrestors on my regulator, it obviously wouldn't have stopped this.  It makes me want to run them on both the torch handle AND the regulators but I have heard that this is too restrictive for the flow.  Any comments?
Reply:Originally Posted by ashley1284Although I run arrestors on my regulator, it obviously wouldn't have stopped this.  It makes me want to run them on both the torch handle AND the regulators but I have heard that this is too restrictive for the flow.  Any comments?
Reply:Glad to hear that everyone made it through this safely.  In regards to flashback arrestors, you should consult with both the torch manufacturer as well as your gas supplier.   Some torches have a flashback arrestor install internally, and adding external arrestors actually creates a safety issue.   Arrestors also have to be sized properly, and installed properly.  If arrestors are undersized, again a safety issue is created.  Too many people have misunderstandings in regards to this serious safety issue.  I personally prefer a torch that has an arrestor installed in the head (Smith for example), as I really don't like holding the equivalent to a hand grenade in my hands.  Dabar, thanks for posting and sharing your learning experience with everyone.  Stay safe!!!
Reply:In addition to getting some new hoses and flashback arrestors, it sounds like Dabar's friend might need to review O/A safety procedures, such as how to safely light and adjust a torch.  The acetylene should always be turned on first, lit, and adjusted until it just stops smoking before oxygen is added.  Ensuring sufficient fuel flow (in excess of the burn rate of the gas being used) is the best way to prevent flashbacks.  The arrestors are just a second line of defense.  I learned this lesson the hard way... Anyway, most of you guys probably already know this stuff.  I'm just mentioning it for the benefit of those who don't.  I thought it needed to be brought up because in the original post it was written that the oxygen was turned on first, then the acetylene, and then lit.  This is just setting yourself up for failure.  Danger Will Robinson!! Dabar, glad nobody got hurt.  Thanks for the post and pics! It would have definitely been time for an underwear change.   Work HARDER, not smarter! ------------------------ Miller Bobcat 250Millermatic 251Lincoln Precision TIG 185Hypertherm PM 600Hobart 135 HandlerOxweld 400 FlameMaster
Reply:I absolutely love your pictures, and commend you on your quick thinking.EVERYONE who works with a torch should know that the first thing to do in the event of a fire, is turn the tank valves off.Its a little surprising to see that the oxygen hose was the one to burn, since the higher oxygen pressure can push its way back into the acetylene side, and cause mixed gases, which can detonate.  A lot of bad things can happen when a torch tip gets clogged.I know you've learned your lesson, and hope others here will take this to heart.  A check-valve/flashback-arrestor set should have prevented this.Thanks for sharing.
Reply:Originally Posted by DSWGood post. It got me thinking about how I do some things. Usually at the house, I leave the tanks strapped up inside the garage and just pay out enough hose to do the few quick cuts in the drive I need to do. Most times I pull the door down so I'll keep any stray sparks from getting into the over filled garage. My 1st thought was what that 4' of flame writhing around would have done if the door had been up. The old car in there with the gas tank right by the door, the misc leaves that always seem to blow in no matter how often I try and clean it out, the gas cans for the blower, mower etc near the door and what a mess that could have been. My next thought was what IF the door had been closed! It's a PITA to get that double door open some times, and I'll bet right then I would not have been in the mood to futz with being sure that door goes straight up evenly, not to mention that the flames would most likely have been between me and the cylinders, both fire extingushers and so on.Time to quit being lazy, and just wheel the tanks out when I need to cut. They're already on a cart, so it's not that big a deal. I know the rosebud has flash arrestors, I'll have to double check the cutting torch.
Reply:Holy Crap!! No pun intended.....zap!I am not completely insane..Some parts are missing Professional Driver on a closed course....Do not attempt.Just because I'm a  dumbass don't mean that you can be too.So DON'T try any of this **** l do at home.
Reply:Finally someone saw the same thing I did !! deadhead put the nuts to the bolts,, by no means am I an expert welder but the thing my uncle and all the books I've read say the same thing!  To light a torch properly etc etc,, turn on the gas and adjust it,, then turn on the oxy and make more adustments,,The big caution here is that burning oxygen alone is hot enough to cut steel and many demos have been done to prove that oxy alone can be used to cut!  that is why it is so important to turn off the oxy first!!  in just such an incedent!!!  turn on oxy last when starting and oxy off first when stopping...????
Reply:seems to me chip lit the torch wrong. no ox until the acetylene is burning sootfree.
Reply:Originally Posted by weldbeadseems to me chip lit the torch wrong. no ox until the acetylene is burning sootfree.
Reply:Check Valves and Flash Back Arrestors should be used. Also a fire extinguisher should always be kept handy. Lucky the fire didnt make it back to the bottle.Kaboom.How to Operate an Oxyacetylene TorchArticle From sore4x4.comBrief Summary:    * If you have not been trained in oxyacetylene welding or brazing, seek out the assistance of a knowledgeable person or enrol in a community college course.    * Oxyacetylene welding is not difficult, but there are a good number of subtle points that should be learned such as: never fully empty an acetylene cylinder or use more than 1/7 the capacity of the cylinder per hour.Safety Considerations:    * Welding is a practical and satisfying art but oxyacetylene welding is potentially dangerous activity.    * Severe and fatal burns and violent building destroying explosions can result from inattention and carelessness. Familiarize yourself with safety procedures and weld safely!    * Before using an oxyacetylene set, ensure that flammable materials such as grease, oil, paint, sawdust etc are cleared from the area and workpieces.    * It is important to wear clean, oil and grease free clothing because oil and grease can spontaneously ignite and burn violently in the presence of pure oxygen.    * The fluxes, filler rods and base metals heated during welding and brazing all release toxic fumes and acetylene gas is highly explosive so ensure adequate ventilation before welding.    * Acetylene is often described as having a sweet garlic like smell. If you can smell it in the air and don't know where it is coming from, evacuate the area immediately. Call the fire department from a phone *outside* of the area as a phone can set off vapors.    * In confined spaces, respirator masks designed for welding can be used. Never weld on containers that have previously contained toxic or flammable substances. Do not weld inside enclosed spaces or in tanks where the only ventilation comes from above - you might suffocate.    * Leather gloves with long cuffs and heavy work boots are recommended. Falling droplets of metal will instantly burn through running shoes and continue burning through the operators foot. Long pants and shirt sleeves should be worn. Do not role up pant legs as the cuffs could catch sparks. Leather aprons and flame proof jackets can be used to protect the operator. Eye protection is also necessary.    * Gas welding does not generate the same UV as arc welding but sparks and infra-red radiation are still very dangerous.    * Before using an oxyacetylene setup, ensure that a fire extinguisher in good working order is present.    * Water does not work on grease fires; a bucket of water can be handy for putting out small wood fires and quenching parts.    * A wet cloth can also be used to extinguish a flame on a hose or fitting. Sand can also be used to put out fires.    * Ensure that the tanks are secured vertically on a cart or chained to a wall. If the cylinders were to fall over and the valve broken off the top, the highly pressurized gases inside will convert the cylinders into rockets capable of smashing through walls.    * On your oxyacetylene torch system there will be three types of valves, the tank valve, the regulator valve, and the torch valve.    * There will be one of them for each gas. The gas in the tanks or cylinders is at high pressure. Oxygen cylinders are generally filled to something like 2200 psi.    * The regulator converts the high pressure gas to a low pressure stream suitable for welding.    * Never attempt to directly use high-pressure gas.    * Do not use pressurized oxygen for blowing dirt out or cleaning clothing. The oxygen can saturate the material making it eight times more flammable!Lighting a Setup torchHere are the steps:   1. Read the safety considerations   2. Ensure that the hoses are untangled and kept well clear of the flame.   3. Make sure that the regulator valves are turned all the way out and the torch valves are closed.   4. Open both tank valves. The valves should be opened slowly to minimize the impact of unleashing highly compressed gases on the regulators. The operator should not stand directly in front of the regulator guages as malfunctioning guages can blow outwards. Turn both regulator valves inwards until you reach the desired pressure.   5. It is recommended that you purge the gas lines before use to ensure that no oxygen is in the acetylene line and vice versa. Ensure that you have adequate ventilation.   6. If the setup has not been used in a while you may wish to check for leaks. With the torch valves closed and the regulators open, shut off the tank valves and observe the line pressure for several minutes. If the pressure falls, there is a leak in the system. Bubble solution can be used to test connections for leaks. Never use a setup with a leak!   7. Open the acetylene torch valve a very small amount and light with a spark lighter.   8. Once the flame is lit, open the acetylene valve just until the flame stops smoking. You should get a flame about 8 inches long with a toothy splintering end.   9. Now open the oxygen valve until the flame loses its feather around its inner core, but no farther than this amount. This is called a "neutral" flame. The mixture of oxygen and fuel gas combine to produce exhaust gases that do not chemically alter the metal to be welded or brazed.NOTE : DO NOT SET THE ACETYLENE REGULATOR VALVE HIGHER THAN 15PSI! If you do, the acetylene can explosively decompose into carbon and hydrogen gas all by itself.    * To shut down the torch, close the oxygen torch valve first, then the acetylene. A 'pop' may occur if you reverse the order.    * The pop throws carbon soot back into the torch, which may partially plug the gas passages.    * Next, close both the tank valves.    * Turn on the torch valves again, one at a time, to bleed any remaining pressure, then close them again.    * Turn the regulator valves until there is no pressure on the adjusting spring and the screw turns freely.
Reply:I run arrestors from my regs, and my Victor torch has some built in on that end. I always light my torches with acetylene first till soot free and then oxygen applied. Never had anything like this happen. I've had a few "pops" in the tip but that's not to be confused with a flashback.
Reply:someone in the safety section is asking about flashback arrestors at the regs and being told that its a bad idea if you already have them built into the torch.Should they be corrected? I think so but I'm no torch expert.
Reply:Originally Posted by kenklingermansomeone in the safety section is asking about flashback arrestors at the regs and being told that its a bad idea if you already have them built into the torch.Should they be corrected? I think so but I'm no torch expert.
Reply:i thought about it some more......and sopmthin dont make no sense..if the flame is in the ox hose...and ox dont support flame by itself.......then some fuel got into the ox hose.....but the fuel is at one fifth the pressure of the ox.....or is it? is the ox regulator set too  low like it was gonna weld not cut??see?????it dont make   sense.......Originally Posted by weldbeadi thought about it some more......and sopmthin dont make no sense..if the flame is in the ox hose...and ox dont support flame by itself.......then some fuel got into the ox hose.....but the fuel is at one fifth the pressure of the ox.....or is it? is the ox regulator set too  low like it was gonna weld not cut??see?????it dont make   sense.......
Reply:Originally Posted by weldbeadi thought about it some more......and sopmthin dont make no sense..if the flame is in the ox hose...and ox dont support flame by itself.......then some fuel got into the ox hose.....but the fuel is at one fifth the pressure of the ox.....or is it? is the ox regulator set too  low like it was gonna weld not cut??see?????it dont make   sense.......
Reply:I think Leadhead is absolutely right, and that is the main reason I light my torches the old way, as has been mentioned - light acetylene first and crank er down until there is no soot, then bring in the oxygen. It is supposed to help keep flashbacks from happening. I do run arrestors, but I light it that way anyway. The other thing I noticed is I don't think purging the lines was mentioned before your friend lit the torch, which is another important part to preventing these kinds of incidents. I am glad no one got hurt.Thanks for posting it dabar - we all need to remember why we should follow safe lighting procedures.Last edited by smyrna5; 01-23-2010 at 04:14 PM.Lincoln 175HD Miller AC/DC ThunderboltSmith AW1, Dillion (Henrob) Mark III, & Smith LittleTorch
Reply:Heres my two cents. When I thought about getting into cutting metal and useing a torch. I did a little research. Victor is one company that buildes flashback arrestors  into their torchs. I bought my set at Tractor Supply $184. This is something you cant mess around with. Dont get old stuff you find at a sale. Spend a little money and be safe.
Reply:Originally Posted by weldbeadi thought about it some more......and sopmthin dont make no sense..if the flame is in the ox hose...and ox dont support flame by itself.......then some fuel got into the ox hose.....but the fuel is at one fifth the pressure of the ox.....or is it? is the ox regulator set too  low like it was gonna weld not cut??see?????it dont make   sense.......
Reply:FYI, my Harris torch came with arrestors on the torch and the tanks.
Reply:I had a similar experience recently. I was cutting metal in the workshop when one of the young fitters started welding nearby. As I noticed the torch had stopped cutting properly I felt the hoses being jerked and thought the fitter was playing games. I flipped up my goggles to discover the jerking was the fitter stomping on the hoses which were on fire. He quickly worked out that turning them off at the tanks was a far better idea.Lesson learnt by the fitter - don't weld next to oxy set hoses!!Last edited by briselec; 01-06-2011 at 03:28 AM.
Reply:Wow ! Good thing nobody got hurt. Originally Posted by dabar39This should probably be posted in the safety forum but I thought more people would see it here.Yesterday I was working on the tail gate hinges on my friend Chip's dump truck. I knew I was going to need a set of torches to do the work, I told Chip that I had one empty bottle of acetylene and the other was just about empty and we would need to get them filled before we could do anything. He said that he has a set of torches and both of his bottles were full. He brought them over and set up the torches, I climbed up into the bed of the dump truck and started to do some grinding on an area to be repaired while Chip was going to cut some patch repair panels for me. I'm not exactly sure what had happened next but I became a real believer in flash back arresters right quick.I didn't see exactly what had happened but saw Chip drop the torch head and suddenly I saw a flame shooting from the Oxygen hose, about three or four feet down the line from the torch head. Chip was kinda trying to kick the torches away from the back of the truck, I jumped down from the back of the truck and ran to the bottles and shut them off in a hurry. I didn't think my fat a$s could move that quick anymore, but it did. I guess seeing flames shooting about four feet out of the hoses while it was slinging around the ground like a snake trying to strike will make anyone move quickly.After my butt checks finally began to unclench and everything settled down for a few minutes I asked him what had exactly had happened. He said that he first cracked the oxygen valve and then open the acetylene valve, struck the striker and the torch fired, popped and went out. He said he then shut the valves back off and repeated the process, only the torch was acting as if it was not getting oxygen, just the orange sooty flame from the acetylene. He said he shut of the acetylene valve again and the torch started vibrating and the next thing he new the oxygen hose burst and erupted in flames. This could have gotten real ugly in a hurry had I not shut the bottles down as quickly as I did. I would not be making this post had we used my torches with flash arresters on them. This is post is more to let the new guys know to NOT take cutting torches lightly, they can be a very useful item, but when not handled correctly things can go bad in a hurry. There has been a lot of discussion on here about proper handling of torches, using the proper safety devices that are available and also about paying attention to your surroundings and others. Had I payed attention and noticed his torches did not have any flash arrestors on them I would have insisted on using my regulators, hoses, and torch head and this never would have happened. When all is said and done the only real damage was to the torch hoses, an extension cord, a cord to the grinder, a pair of soiled boxers and to the torch head itself. The torch will have to be sent off and rebuilt before being used again as I'm sure some damage was done internally to it and should not be used until it has been checked out by a qualified repair center.
Reply:That rumbling in the handle is a telltale sign of fire going on inside of there. not a good thing to feel. Glad no one was hurt.
Reply:Originally Posted by HighlandwelderI personally prefer a torch that has an arrestor installed in the head (Smith for example), as I really don't like holding the equivalent to a hand grenade in my hands.Stay safe!!!
Reply:Someday you will not be able to go into a store and buy a oxy-acetylene rig without showing that you have had a beginning course or some kind of instruction.Many pre 1981 tanks could be sitting around too. Not up to date.Sometimes I have seen tanks sitting for years unused.I always inform the owners to be careful and get them checked out and updated before reusing.I have seen it many times.Not shutting off torches in the proper order, also and not bleeding regulators properly.REVIEW yourself from time to time.AWS certified welding inspectorAWS certified welder
Reply:Proper pressure, proper bleed, proper startup and shutdown.  Sounds like there was an improper bleed after use, and no bleed before use, and some fuel was in the o2 hose.Bleed after use, bleed before use.  O/A can go real wrong real fast.  Other than trained professionals, i have yet to see a hobby welder bleed at all, or start properly.  I cringe when i see people crack boths valves and hit it with a sparker.Syncrowave 350Coolmate 3Millermatic 251Spoolmatic 30A
Reply:Originally Posted by Donald Branscom. . .Many pre 1981 tanks could be sitting around too. Not up to date.Sometimes I have seen tanks sitting for years unused. . . .
Reply:Originally Posted by Donald BranscomSomeday you will not be able to go into a store and buy a oxy-acetylene rig without showing that you have had a beginning course or some kind of instruction.Many pre 1981 tanks could be sitting around too. Not up to date.Sometimes I have seen tanks sitting for years unused.I always inform the owners to be careful and get them checked out and updated before reusing.I have seen it many times.Not shutting off torches in the proper order, also and not bleeding regulators properly.REVIEW yourself from time to time.
Reply:Originally Posted by denrepOkay, I'll bite.What's supposedly up with the pre-1981 cylinders?
Reply:Glad no one was hurt! I've had a few mishaps with o/a setups.Always check hoses & regs for leaks,oil,grease.YOU DON'T NEED A SPARK TO IGNITE OXY! Contact with grease/oil will cause oxy to flash into a big fireball!! Also,in the event of a fire which results in an insurance claim,presence of o/a setup would likely void homeowners ins. policy.
Reply:I know that I'm starting to see cylinders in service that are pushing a 100 years old now.All of the test stamps have probably have done more harm to the cylinders than anything else. I just wondered if '81 was a big change year somewhere?Good Luck
Reply:Originally Posted by denrepI know that I'm starting to see cylinders in service that are pushing a 100 years old now.All of the test stamps have probably have done more harm to the cylinders than anything else. I just wondered if '81 was a big change year somewhere?Good Luck
Reply:Originally Posted by n20junkieProper pressure, proper bleed, proper startup and shutdown.  Sounds like there was an improper bleed after use, and no bleed before use, and some fuel was in the o2 hose.Bleed after use, bleed before use.  O/A can go real wrong real fast.  Other than trained professionals, i have yet to see a hobby welder bleed at all, or start properly.  I cringe when i see people crack boths valves and hit it with a sparker.
Reply:just curious when i start my torch first off i close the main valve and empty both hoses then back out the regulators every time im not going to use the torch for a while (as in done for the day). so when i go to light the torch i open the mains dial in the regulators then i turn the gas about 1/4 turn and light it then i get the flame depending on what im doing to where its has no oxy and its as big as it can get with out leaving the tip. then i turn the o2 up via the knob by the cutting lever. and to shut it off i kill the o2 then the gas. and blead when done...
Reply:In school the books always said to turn off the O2 first, but all the teachers always said to turn the gas off first? who is right?
Reply:How much worse could it have been?  I mean, it could have burned its way back to the tank but once it got to the tank it would have run out of fuel (the hose) and the fire would basically self extinguish.  Yeah, hose fires will get your heart going but they aren't going to blow up an O2 tank.And for which to turn off first, the manuals all say to to the O2 first.  I turn off the gas first.  The excess O2 will blow the flame out.  I've had torches in the past with valves that leaked by.  Turning off O2 first would diminish the flame to the point that it was burning within the torch tip out of sight.  Set the torch down and a few minutes later the nearest rag was on fire.  Crack the O2 valve open and it would blow the flame out of the torch.  Then, no more mystery fires,
Reply:"A before O or up you go!" Always Fuel then Oxygen, then to turn off, fuel then oxygen again.We always leave the extra oxygen valve on. That valve I believe acts as a flow restrictor  to set the amount which passes through.Last edited by oxygen454; 01-09-2011 at 04:41 AM.
Reply:Originally Posted by 76GMC1500How much worse could it have been?  I mean, it could have burned its way back to the tank but once it got to the tank it would have run out of fuel (the hose) and the fire would basically self extinguish.  Yeah, hose fires will get your heart going but they aren't going to blow up an O2 tank,
Reply:Thats got me thinking. I somehow got grease on the oxygen regulator on the bottle threads and on the back of the gauges. I cleaned it off well with a rag. Maybe I should wash it with soap and water...