Swede Posted October 6, 2009 Posted October 6, 2009 Making multiple small batches as opposed to one larger batch is often more dangerous. The amount of BP the guy made is not unusual at all for an advanced hobbyist. I really don't see too much wrong so long as the humidity is high. It looks like he is using a plastic garbage bag to collect the BP, and the image of the BP dust flowing down a garbage bag makes me think static generation. Plastics are great, but they do have a greater potential for static charge than paper or wood. If the bottom of the garbage bag is solidly grounded, then there is probably little danger. But if you wanted to make the picture perfect, perhaps one could use one of those "greenie" paper lawn bags (despite the mess); get rid of the watch, and a face shield might allow survival with eyesight and face still intact, although honestly, I think the burns would kill. It's the nature of the beast. When you work on such a scale, you are dealing with lethal quantities of energetic materials. Likewise, every time you hit the highway, you are in a potentially lethal situation. In the Air Force, we wore Nomex flight suits and gloves for fire protection. These are available surplus at almost any Army/Navy store, along with the gloves. I guess if you really wanted to put the odds in your favor, a nomex flight suit might not be a bad thing to have. But I do not know of the potential for static with nomex. It might make it worse.
NightHawkInLight Posted October 6, 2009 Posted October 6, 2009 I have talked with several demolitions guys in the last few months. For static protection they use a bracelet with a wire leading to a ground. It wouldn't be a bad idea. For clothing however, I don't know how much static would actually be alleviated. For both static and fire protection I don't think there's any better way to go than leather. It stands up to the heat of a welding arc at only an inch or two away. I have no doubt that a BP flash wouldn't cause any more than a mildly uncomfortable temperature within the clothing. I could probably ignite a good 10 grams of BP in my hand wearing my welding gloves without injury. Unfortunately, they're a bit thick for delicate work.
scarbelly Posted October 7, 2009 Posted October 7, 2009 (edited) I just did some quick research on nomex flight suits, and it seems that they are flame retardant, and anti-static. If those are true, that sounds like it would be one helluva good investment. EDIT: after a little more research, it appears that the original nomex is actually (like many plastics) quite the static-y mess. There is a different type, IIIA I believe, that is a blend of Kevlar, Nomex, and an anti-static fabric. A seller had this to say:"Nuisance static has been a perceived problem of NOMEX, IIIA addresses this concern. Antistatic performance of NOMEX IIIA is not dependent on ambient relative humidity. It is important to recognize that NOMEX IIIA is designed to combat nuisance static only and, like 100% cotton, it should not be considered for use in critical static control applications." Edited October 7, 2009 by scarbelly
Swede Posted October 7, 2009 Posted October 7, 2009 Thanks for doing the grunt work with that research. So for preparing static-sensitive comps, it sounds like it's not appropriate. But anytime else, perhaps when working a show, any time you're not worried about static but ARE worried about fire, it might not be bad to have one. They are extremely comfortable, too, have pockets all over the place, and like most mil-surplus, are very well made. I used 4 nomex "bags" over 7 years of hectic active duty, and at the end, they were still all very serviceable.
ExplosiveCoek Posted October 7, 2009 Posted October 7, 2009 What is wrong with that guy wearing a watch? I also can't see how some static electricity could produce a spark significant enough to set of the meal powder.. @ NightHawk, for using such a grounded bracelet, what kind of stuff are they using as 'wire' to get too the grounded spot? And how do they actually ground it, just ramming a metal pole in the ground?
NightHawkInLight Posted October 7, 2009 Posted October 7, 2009 What is wrong with that guy wearing a watch? I also can't see how some static electricity could produce a spark significant enough to set of the meal powder.. @ NightHawk, for using such a grounded bracelet, what kind of stuff are they using as 'wire' to get too the grounded spot? And how do they actually ground it, just ramming a metal pole in the ground?I would suspect a static spark would be most likely to cause ignition to particles suspended in air just above the powders surface. About the bracelet, I did not ask enough questions to know what cable was used. I pictured the old style coiled telephone chord. I think that could work quite well attached to a sheet of copper on the inside of a velcro bracelet. For the ground, yes, it would just be a steak pounded deep into the ground.
Ericz Posted October 7, 2009 Posted October 7, 2009 (edited) Isnt it true, that the cloud of meal dust ignites when there is a static spark ? I dont think that meal would ignite by a spark on a batch of 100 gram laying on something , its the dust whats flamable ? correct me if iam wrong. GRtz lol >>> i was 1 munite later , kinda same post would suspect a static spark would be most likely to cause ignition to particles suspended in air just above the powders surface^^ Edited October 7, 2009 by Ericz
Mumbles Posted October 7, 2009 Posted October 7, 2009 Yes, both the dust and the condensed powder can be set off by static in theory. The dust probably more likely as there is less resistance around it. The watch isn't a static thing, but a direct impact or scraping against the screen issue.
Swede Posted October 8, 2009 Posted October 8, 2009 I think Mumbles is correct on the watch, but it is simply habit and sound safety to remove all jewelry when doing almost any mechanical work. I haven't worn a wedding ring for years because of my work with a lathe, and with welders, and my spouse is cool with it. WARNING - GRAPHIC IMAGES POSSIBLE: Google "degloving" or "deglove" injury for some of the grossest damage imaginable, all caused by wedding rings. Basically, if your finger stays on, what happens is all of the skin is gone, leaving you looking like skeletor on one finger. Sorry, not fireworks related, but I think young men newly married need to know. Wearing rings is really dangerous in sports and mechanical work.
Richtee Posted October 8, 2009 Posted October 8, 2009 . Sorry, not fireworks related, but I think young men newly married need to know. Wearing rings is really dangerous in sports and mechanical work. Mine is in a case, and comes out for special ocassions. Not a good thing inside poswer supplies or electrical panels either. A brand of the REAL kind isn't pretty either.
TheSidewinder Posted October 8, 2009 Author Posted October 8, 2009 Auto mechanics seldom wear watches or wedding rings, either. When I was doing my EMT training back in 1975, we had a transport of a mechanic whose wedding ring shorted across the contacts of the starter motor, which was "only" 12 volts. But.... It *instantly* heated up to red-hot on his finger. He had no time to react. You can imagine the result. And the smell was indescribable. Burnt Pork, anyone? His finger had to be amputated due to the extensive tissue damage. It even charred the bone within it. Anecdotal story, and not pyro-related, but an example of what can go wrong. Stay safe, folks.
lostfido Posted October 9, 2009 Posted October 9, 2009 Auto mechanics seldom wear watches or wedding rings, either. When I was doing my EMT training back in 1975, we had a transport of a mechanic whose wedding ring shorted across the contacts of the starter motor, which was "only" 12 volts. My dad was a mechanic all his life and had that exact thing happen to him, only not as severe. I can remember as a kid when he did it and how gross it looked. My old man was a stubborn "Swede" (I wonder where I get my stubborness from) and never went to a doctor or the hospital, so he let it heal on its own. By the time he passed away, you could hardly even see the ring at all because the skin of his finger had kind of encased it. Needless to say that wedding ring went to the grave with him. I may have to print this and show it to the wife, maybe she will believe me that mechanics don't wear wedding rings!!!
Swede Posted October 10, 2009 Posted October 10, 2009 I may have to print this and show it to the wife, maybe she will believe me that mechanics don't wear wedding rings!!! I have never heard of a wife objecting to "no ring" on an active mechanical/electrical spouse if shown a degloving picture. That's a last resort, because the pictures are nasty, but a wife needs to understand the reality of it. I heard of a guy who went up to slam-dunk a basketball, felt a sharp pain, looked up, and saw his finger hanging from a part of the net frame. The ring had caught. That's enough wedding ring stuff from me!
handymanherb Posted July 19, 2010 Posted July 19, 2010 That's the one thing that has always stopped me so far, Dad and my brother saying when things go bad, it's real bad, so we been trying to get in a Club in Florida for 5 years and gave up,they never respond to calls or e-mails, we even oftered just to help and clean up afterwards to show we are willing to work for fireworks. I guess in Florida you have to get good first and then they invite you to join, after I learn to do it safe what's the point of a club except you get to watch what other are doing. But safety is number one, I don't want to hurt anyone including me, so I'll keep reading.
Mumbles Posted July 19, 2010 Posted July 19, 2010 Usually you need to get to know someone in the FPAG to recommend you. I'd suggest joining passfire, there are lots of members there who can vouch and help you out.
Skycastlefish Posted July 20, 2010 Posted July 20, 2010 Every time I read this thread I read it in its entirety - and every time I notice something new
handymanherb Posted July 21, 2010 Posted July 21, 2010 Usually you need to get to know someone in the FPAG to recommend you. I'd suggest joining passfire, there are lots of members there who can vouch and help you out. Ok I'll do that too, we have been leaving mesages on the club answering machine and e-mails, you think we would have gotten something back from them , it not like were kids anymore. Want to learn safety and keep the saying on my shirt funny. http://img140.imageshack.us/img140/4981/img1963b2009reunion.jpg
swervedriver Posted July 21, 2010 Posted July 21, 2010 I spoke to a guy from FPAG a while back. Seemed to be receptive enough. It's true you do need a sponsor, but didn't seem to hard to do from speaking with him. He would have done it. I'm 3.5 hours south of them so I haven't made the trek up there yet.
DdDodd Posted July 9, 2011 Posted July 9, 2011 (edited) After reading through this article, I am concerned over my own BP milling. My jar is a regular 6" PVC pipe, topped with a rubber cap. When emptying the container (20oz batch), it is done into a Home Depot Bucket fitted with a galvanized steel screen. The milling media I use is lead balls of course. The screen bucket sits inside another bucket that collects the BP being separated. I always wear cotton/denim, work directly on the ground, and wear no jewelry. My main concern now is the jar itself and the process of dumping the contents, including the media onto the steel screen. If I am missing something critical, please let me know asap... Edited July 9, 2011 by DdDodd
bubba153 Posted November 5, 2012 Posted November 5, 2012 After reading through this article, I am concerned over my own BP milling. My jar is a regular 6" PVC pipe, topped with a rubber cap. When emptying the container (20oz batch), it is done into a Home Depot Bucket fitted with a galvanized steel screen. The milling media I use is lead balls of course. The screen bucket sits inside another bucket that collects the BP being separated. I always wear cotton/denim, work directly on the ground, and wear no jewelry. My main concern now is the jar itself and the process of dumping the contents, including the media onto the steel screen. If I am missing something critical, please let me know asap... I also would like to know if this particular method offers significant danger, as it's exactly the process I use.
Arthur Posted November 5, 2012 Posted November 5, 2012 When you have truly minimised the risk and hazards of the process then it's time to consider PPE. I see pics of people from warmer states working in Tee shirt and shorts, but that's NO protection. I've gone the the trouble and expense of genuine Nomex trousers and a flash resistant long sleeve shirt, I sometimes wear a nomex flash hood too. If I'm playing with fire that's an awful % of burns reduced in severity if anything goes wrong, and anyone soon realises that burns HURT.
gelamex Posted November 7, 2012 Posted November 7, 2012 Having had to deal with friend who have suffered the consequences of high energy but low tech devices I have an enormous respect for all energetic materials. Looking at photos of some of the 'safety' screens makes me wonder just how effective most would be if a catastrophic situation arose. Most folks massively underestimate the release of energy and subsequent damage that small quantities can cause. As for burns; having a lad rolling on the ground screaming for someone to shoot him is a thought that always comes back when handling these materials. An interesting point. One of our lads survived an IED of 5Kg of semtex-H when only two metres from the device. The device had been placed behind an aluminium screen; the terrs expecting the screen to become shrapnel. What actually occurred was that the screen stretched and bowed into a rather large bowl absorbing a great deal of energy. The screen still intact, hit our lad, knocked him over but he was uninjured. This experience led me to include a sheet of aluminium 2mm thick as part of my shield sandwich.
blewupmyhouse Posted February 4, 2013 Posted February 4, 2013 A week after seeing this I too had a misshap I blew my house up lucky no one got serriously hurt cost me two years in prison and a large debut all due to being careless and now im back and much more aware of the concicunsies of this hobby passion? Be safe and teach thouse who want to learn.
a_bab Posted February 4, 2013 Posted February 4, 2013 After 2 years in prison I'd expect anyone but the toughest quitting this hobby. Please detail how and what happened so others can learn.
Paravani Posted June 27, 2014 Posted June 27, 2014 Hi everybody! -- My first post -- Thanks for pinning this thread. It's the second thread I've read all the way through here (the first was a thread on ATF licensing/permits), and that's probably the best beginning I could ever have made here: learning the law, and extreme caution, before ever learning to mix BP or make any of the other interesting, challenging, and very scary items you all make as a "hobby". Last week a fireworks mfgr had an accident in my home state that killed one longtime, very experienced, 75-year-old employee and injured two others. Cautionary tales definitely have their value: hearing them and remembering them (instead of saying, "That could never happen to me") will hopefully help me live a long, long life in spite of being drawn to learn a new hobby. I'm a stickler for the law, too -- comes from being so claustrophobic that I don't even want to consider spending a single night in jail, even if my attorney could get me out the very next day -- so please grant me some "newbie" latitude, but it sounds as if a couple of these "accidents" may have been due to not following the rules? For instance, once an explosive material is made, isn't it supposed to be stored in a fireproof magazine, and not left in a garbage bag next to the work area? Oh, and about static: My background is electrical engineering, and we are far more anti-static than even you folks. The tiniest charge can toast a modern micro-electronics chip, so we always wear ground straps and work on "ground planes" when breadboarding and/or testing circuits. A simple ground plane can be a metal bench that is physically grounded -- i.e., wired to a ground cable. A ground strap is a bracelet that makes contact with your skin and is also physically grounded. In the electronics industry, our flooring, carpet, and protective clothing are all anti-static. If you really want to be ultra-cautious, you might look into the "bunny suits" used in clean rooms where electronics are manufactured. These bunny suits are cut generously and very lightweight, so could be worn over fire-resistant PPE. I'm still in the "learning newbie" stage of this. I'll research more options for anti-static PPE that might be found in the electronics industry, and share with y'all what I learn as I learn it. -- Paravani
Recommended Posts