Welding and Breathing Protection
Being productive without gassing yourself- or others
Text, photos and video by Tom Hintz
Posted – 8-23-2011
For the most part welders recognize the need to protect themselves from the heat and intense light generated by all welding processes. Unfortunately far too many of those same welders do little to nothing to control what they (and nearby others) breathe in a welding environment. Because smoke and other gaseous materials don’t go away when the arc stops we have to look at the environment as a whole for an hour or so after the welding has stopped.
We have to realize that welding generates uniquely high temperatures that can literally convert an apparently benign material into a dangerous gas. Not so long ago welders were using a wide array of commercial and shop-mixed concoctions that were applied to the metal being welded in an attempt to control spatter. Sometimes they unintentionally included materials that were in some way chlorinated but in their original state remained relatively harmless. However, when materials containing chlorine were exposed to the intense heat of welding they could be changed into phosgene gas. Phosgene is an exceptionally nasty poisonous gas that was so lethal and produced such horrendous injuries that it was banned in 1925 from being used in wars! The point is that we don’t know for sure what welding over some materials will produce. Modern anti-spatter materials are purpose designed for welding and I for one am not going to risk gassing myself trying to save the few dollars that they cost.
Clean the Metal
Most welders clean away some of the surface contamination right on the weld line and where they want to put the ground. That’s a good start but we need to extend that cleaning far enough out from the weld to prevent anything on the metal from being burned and converted to fumes as we weld.
I also refrain from using things like paint stripper and the like because it leaves a residue behind. When I need to clean the metal I use a grinding disk or wire brush in my 4-1/2” angle grinders. Using paint strippers or other cleaning agents just before welding just does not make good sense to me. This is also why I don’t spray anything on the metal other than purpose designed commercial anti-spatter materials. In addition to reducing the fumes being created, it is much easier to get a good weld when you are working with clean material.
One of the easiest things we can do is to use a fan to help evacuate fumes and circulate fresh air by the person welding. I almost always weld at one of my (open) overhead garage doors. I have an effective fan that I set in the garage space so that it blows across me while encouraging the welding plume out of the door. It’s not perfect but it does a surprisingly good job for my part time welding.
In addition to moving the smoke away from me the air being forced by me dilutes the fumes being created by my welding. That rush of relatively fresh air can dramatically reduce the potency of whatever may be in the smoke to help keep me healthy.
A built in exhaust fan system can be very helpful if not mandatory for a real shop setting as long as it is accurately sized for the shop space size. A good exhaust fan also requires a way for fresh air to get into the shop space or the fan can stall out and essentially stop moving air. These types of exhaust systems change the air out a number of times per hour so short of making it windy in the shop, more exchanges per hour the better.
Wearing a purpose designed respirator mask takes the next step towards increasing your protection. Any dust mask is not a legitimate answer because it is designed for the wrong things. When I am in doubt about the fumes I wear a Cool Flow mask from 3M because it was designed from the ground up to offer protection in the welding environment. It is also effective for many sanding, grinding and soldering operations that may be related to work in a welding area. 3M literature states that the 3M Metal Working Cool Flow Respirator filters solid particulates, metal fumes from welding and cutting as well as liquid or non-oil based particles from sprays that do not also emit harmful vapors. If your job or shop has a standard to meet this mask conforms to NIOSH (National Institute for Occupational Safety and Health) 42 CFR 84 N95 requirements.
The 3M Metal Working Cool Flow Respirator body is made from what 3M calls “Advanced Electret Media” which is a microfiber material that is electrostatically charged to attract particles without hampering breathing. They also include another 3M design "Welding Web" protective layers that are flame retardant. At the front of the mask is “Cool Flow Exhalation Valve” that opens when you exhale to get your warm breath out and then it closes when you inhale to filter the incoming air. The valve is colored black so that you can tell the welding from similar looking sanding masks that have a light colored valve.
The mask is held in place by a pair of adjustable elastic bands so it can be both secure and comfortable. A thin, formable metal brace at the bridge of the nose makes it easy to seal the 3M Metal Working Cool Flow Respirator to insure filtering when you inhale and to prevent fogging of glasses or helmet lenses when you exhale.
In the Shop
I nearly did not do this story because I thought these simple precautions would be essentially standard already. Not so. Significant numbers of home and small-shop welders seem to think they are impervious to the airborne contaminates or just do not understand the problem. I also have been guilty of not taking all of the precautions available to me for little to no cost.
The fan and other simple ventilation schemes are self-explanatory other than we have to be careful of where we aim the exhaust. If your shop door or window is close to an occupied building, blowing our welding fumes that way just exposes more people. In those situations finding a different direction may be necessary or consider a stack that exhausts the contaminated sir upwards.
Not spraying chemicals on things we are going to weld also seems to be a no-brainer but is not accepted universally as people are still trying to limit spatter with things that were not designed for the job. Maybe not as many but if you are one of them, consider changing to purpose designed anti-spatter sprays that are both cheap and safe.
I know that a bunch of the home and small-shop welding world was not even aware that a simple welding facemask even exists. They do, they are cheap and they work. I was one of the uninformed but am now informed and have a new box of the 3M Metal Working Cool Flow Respirator masks in my shop. There are 10 masks in the box which cost me about $15. Since each mask seems to have a very long lifespan this is a very low-cost but highly effective safety measure we should be using.
Using the 3M Metal Working Cool Flow Respirator is easy and comfortable. I have not had to adjust the straps from where they were out of the box and pinching the metal nose strip to fit really does take just a –pinch. The exhalation valve has proven to be a very good idea that helps prevent my helmet lens from fogging up. There is no apparent restriction to the airflow which makes breathing totally normal. I suspect that if you notice any restriction it is time to replace the mask. And no, wearing the 3M Metal Working Cool Flow Respirator does not hold my welding helmet up!
Welders in general and the home, small-shop crowd in particular need to wake up and take the simple precautions to keep from breathing things we don’t need to be breathing. These are simple, easy-to-do things that do nothing to impede welding or productivity. If anything you might be more productive with a clearer head and less coughing.
All of the steps we looked at here are very cheap and can be effective if applied correctly. The 3M Metal Working Cool Flow Respirator is very easy to use and in all of my use during this evaluation seems very effective. I can’t find a single good excuse for not using this mask anytime you are welding.
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