Help with shop ventilation

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Not sure if this should be in the safety forum...I need some advice on ventilating my basement shop for some occasional MIG welding. I live in a row home, so my basement is narrow and long. Space is tight.My idea is to use a 4 inch duct to suck out the fumes. For the blower, I was thinking of using a dust collector from HF that moves 1000 CFM for a couple reasons. 1) my basement is below ground and has no windows to open. The two small windows are cinder blocked over. So I plan on cutting out a 4 inch drier style vent and running a 4 inch duct about 25 feet to where I'd be welding.  So I think simple exhaust fan or inline duct fan won't be powerful enough.OSHA calls for like 600 CFM 12" away from the welding  I think? 2) The dust collector is on clearance for $60 and could perform double duty for my table saw maybe if I unhook it from the welding exhaust duct.Question is, hopefully it would be enough air, but also would 1000CFM be too powerful and suck away shielding gas. Should I install an exhaust hood over my table, or position the duct tube close to the weld? I gather its a matter of experimentation. As long as I can suck out fumes so they don't go upstairs.What do you guys think?
Reply:The HF would be fine just don't use the dust bags if it has then  you might want a slide valve so you can adjust the air flow
Reply:I'm more concerned about your health. You're going to want to find a way to get fresh air blowing into the basement and the old air being sucked out on the opposite end. The dust collector itself will suck some air in from the basement entrance, but you would have a much more efficient air flow if you could also blow air in. That way you'll have a constant flow going through the entire room. I've got 24' ceilings in my shop and a 16' wide bay door that I keep open and ceiling fans running and a floor fan moving 11,000 CFM, and if I step out for a while and come back in, I can still see it's a little foggy in there. Make sure at the very least you wear a respirator or get a PAPR welding system.John 3:16(2) Miller Pheonix 456(2) Millermertic 252Dynasty 210DXHobart 210MVPDoringer D350 SA Cold SawScotchman 350LT Cold SawWebb 10x50 MillWebb 15x40 LatheGeka Bendicrop Ironworker
Reply:Originally Posted by EcondronI'm more concerned about your health. You're going to want to find a way to get fresh air blowing into the basement and the old air being sucked out on the opposite end. The dust collector itself will suck some air in from the basement entrance, but you would have a much more efficient air flow if you could also blow air in. That way you'll have a constant flow going through the entire room. I've got 24' ceilings in my shop and a 16' wide bay door that I keep open and ceiling fans running and a floor fan moving 11,000 CFM, and if I step out for a while and come back in, I can still see it's a little foggy in there. Make sure at the very least you wear a respirator or get a PAPR welding system.
Reply:It sounds like your basement is essentially a confined space.  Your health is a priority.  I can understand why you may want to weld in your basement  during the winter but you should carefully consider the issues before moving forward.  I am reasonably sure that a dust collector 4" exhaust/fans based solution won't get you where you want to go safely.  A PAPR is not designed for confined space welding.  Take a good look at the air quality equipment that industry uses for confined space operations.  Confined space safety isn't cheap or easy.  Get it wrong and you may pay a very high price.  Besides the air contaminants that welding produces, you will have a far amount of shielding gas contaminants to deal with.  Oxygen for breathing is precious when you have mucked up the confined space air that you are working in.What every you decide, please don't short change your safety.Regards
Reply:You comment on using the dust collector as double duty with the table saw worries me.Sound like you want to do wood working as well as welding in a fairly tight space. Not really the best idea in the world. Mig welding, even with solid wire and gas tosses hot BB's quite a distance. Wood dust is ready made tinder for starting fires. I've seen several small fires start from weld spatter falling on saw dust, dried leaves, old paper towels and so on. Usually they just sit and smolder for a while just waiting for conditions to become right to burst into flames. It often takes a bit for this to happen, so these fires are "sneaky" happening some times after you get done.I'd personally be leery of welding even in a completely empty basement. The typical basement full of clutter would be a night mare of hidden nooks and crannies for fires to smolder and wait. A shop used also for wood working sounds about as smart as deciding to weld in a gun powder plant or fire works factory with out any precautions.All good ventilation is going to do with this issue is make it a lot easier for the fire to get going..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:Can't help you with the wood dust, as I would probably go Harbor Freight. But I use a Lincoln Miniflex fume extractor with the pickup piggybacked to the torch on my push pull Miller XR run while we living 5356 alum. Works excellent.B-C on this forum bought one for tig in his garage for alum in hidps garage. It has a voltage sensor on the top to lay you ground cable on and will only power up when on are welding. Or on can set to continuous. Give him a shout if you are interested as well.Weld like a "WELDOR", not a wel-"DERR" MillerDynasty700DX,Dynasty350DX4ea,Dynasty200DX,Li  ncolnSW200-2ea.,MillerMatic350P,MillerMatic200w/spoolgun,MKCobraMig260,Lincoln SP-170T,PlasmaCam/Hypertherm1250,HFProTig2ea,MigMax1ea.
Reply:That Lincoln Miniflex looks very cool. The documentation says it moves 135 CFM . So I'm sure 1000 CFM minus the loss in the duct will be overkill in theory . DSW, your right. Those BBs are a concern of mine. I would have to vaccume up any dust before welding. I'm not sure if my basement is a confined space or not. Its tight, but its about 12 x 65 - I forget . None the less, its a going to be a pain in the arse to work in. I'm going to see how long I can hack it outside