Supplied Air Mask for Painting?

[Jes Andersen]

Although my current project is not of the OD variety, I have some painting to do and after looking at the various types of paint using activators or hardeners, am wondering about a supplied air respirator. Years ago, we painted with just a half mask but paints have changed. I don't have a booth and would be painting outside. This one is construction equipment but I do have a couple of M37s ready for a repaint further back in the line.

For those of you that use supplied air masks, what do you have and what are your opinions of the setup? I did a search here and on other forums and the results are all over the place.

Thanks in advance for any feedback

[chris vickery]

Hi Jes

It's up to you but if you are painting outside, you could opt to use a full face respirator, non air supplied. It may get hot or even steam up but it is an option if you do not want to go the full route of air supplied equipment.
With air supplied equipment you will need a supply of breathing grade air as well, not just simply tapped into an ordinary airline. So this means use of a compressed air system with the correct filters and humidifier or use of breathing grade compressed gas from bottles. The full face respirator doe offer protection to the eyes and skin on the face vs the half mask. Many of todays paints can be nasty depending on what they are. I think if you are using ordinary alkyd enamel you'd be OK with a half mask.
Check around and ask lots of questions.
Personally when I paint outdoors I use the half mask and safety googles.

[Phil Waterman]

Hi Jess

I've been using a supply air breathing system in my shop for more than 20 years. It is rigged to supply air to my welding helmet, blasting and grinding hoods and most important to my paint masks.

It draws fresh air from out side the shop and feeds it via high speed squirrel cage blower through a 2" pipe to a central point in the shop at the ceiling then via military grade breathing air hose to what ever hood I'm using. This is all home made and works like a dream. It puts enough air through any of the helmets that there is a constant outflow.

Once you have painted with a supply air system you will never want to paint any other way. I have half mask and full face for painting don't really like the full face because I wear glasses. But for certain types of paint I use the full face. Unlike the filter type masks you don't smell paint at all there is no worry about are the filters style good.

I went over to it for health reasons but now that I've been using it all these years I wouldn't think of painting without it. Even painting Por15 with a brush I use it, great at the end of the day to still have your sense of taste and no head ache.

There have been a couple of threads on MLU about this topic which I will try and find.

Added some photos, as you can see it is nothing fancy but it sure works, adding the full hood to the back of the helmets is of course necessary. You would be surprised how much adding a full hood to the back of auto darkening welding hood improves your vision of the weld, no back reflection and with the air stream directed directly down the the inside of the glass it doesn't fog at all.


Cheers Phil

[rob love]

Tecnically, if you are painting with hardeners, you have to use an air supplied hood. The filters on your regular mask will absorb the isocyanates for so long, then they won`t.

I have a MSA brand filter-regulator unit at work which will filter regular line air into breathable air. I still have to get the right mask to go with it, although I see there are set-ups to supply air to some of the regular filter style full face masks such as the 3M brands.

Currently, I usually use a full face mask for spraying the POR-15. I normally just use a half mask for enamels which I use as the top coat.


Phil: I like your system and have thought of assembling something similar although perhaps a little bit portable. Of course, the one concern is that you have to worry about the source of the air into the blower. Not much point to it all if the paint fumes are drifting or exhausting near to the squirrel cage. I`m sure that`s not the case in your stationary set-up.

[chris vickery]

Many paint shops actually use a battery pack compressor unit which is attached via a waist belt and is a totally self contained system. It alleviates the need to drag hoses around and be tethered and eliminates the costs of a separate compressor system. I think they are over $1500... I suppose it comes down to how often you are using it, exposures, types of paints etc. More is better when it comes to protection but it also comes down to dollar and cents.
Re: Phil, if you can smell paint at all with a half mask it I not correctly fitted. This is a common mistake many people make is in purchasing the incorrect size and type of mask. It is also imperative to be clean shaven. At work, we must be fit tested to ensure the adequate size and type of respirator is issued and it is worn correctly.
Also, to get away from welding fumes there are a couple options. Low profile half mask which will fit under a welding helmet coupled with a smoke extraction system. Personally, I hate to be tied up with hoses when trying to move around with any kind of helmet/mask etc. Its OK for bench work but not much else.

[Phil Waterman]

Hi Rob & Chris

The blower is mounted on the shady gable of the barn it has 8 inch hole through wall so is drawing outside air. It is now hard piped with smooth 2 inch pipe which increased the flow significantly. Have several sections of the OD flex you see in the pictures so that you can walk around entire shop.

When really spraying there are two 2400 cfm fans blowing out the other end of the shop.

Your point about dragging the hose around is true, but for me it is either drag the hose or not do it.

This all started for me because of steaming up my welding helmet, but I quickly noticed that didn't notice any fumes when welding, so the next time I was painting just took the auto dim unit out and just left the clear shield plate in. Having a blower that really delivers a large volume of air if you are going go the home built approach.

Question for you guys who are more involved with the professional side of painting, my understanding is that canister type filters start loosing their chemical absorption as soon as the sealed filter package is opened. So that for those of us who paint occasionally the filters may not be really working?




Cheers Phil

[Jes Andersen]

Thanks for all the feedback. One of the reasons I asked here is that most of us do a bit of everything in our hobby. I have never used a welding respirator but am beginning to think it might be wise. A recent illness has left me with concerns about breathing in all that stuff that I used to. I like Phil's homebuilt setup and think I could come up with something that would work well. There are filters available that could be incorporated for that extra step. The units I have seen available locally are HobbyAir and one that KMS Tools sells. The Hobby air is a turbine and the one KMS sells has a compressor at double the price. I have not checked with the body shop suppliers but know that this gets expensive. I do have both a half mask and a full face. I don't wear glasses any more, so can use the half mask. I spent a bit of time with the paint supplier on Friday and after much discussion, they felt I would be ok with the full mask. I pulled the MSDS on some of the paints we discussed, and as Rob mentioned they require a supplied air setup. 3M has a changeout schedule for cartridges and if followed one should be pretty safe with most products. The problem is once you smell the paint, you are already exposed. Fit, as mentioned is a problem and I have always had trouble getting even cheap masks to seal.

I would send this out to get done but its all apart, heavy and on a small island without ferry service. To top it off I miss the tractor for its heavy lift ability. Maybe a roller and brush will work

[chris vickery]

Jes
I never knew much about fit testing until I actually went for one. We were assigned to work at Koch fertilizer in Brandon MB. As Rob L will attest, this place is basically a death trap where everything can and will kill you. They are makers of very nasty items like Anhydrous ammonia to name but one...
When I went through a fit test the representative at the safety supply in Toronto actually puts you through a video presentation, followed by a knowledge test. They try different masks on you to determine the best fit. The mask is hooked up to a computer and air system which checks various items. You are exposed to a smoke test. Once all this is done you are basically ready to don and use respiratory protection.
The one issue that surprised me was actually how snug a respirator should be while worn. Tight actually. I think too often the home mechanic thinks he is doing good but is actually doing very little. A bad seal is the same as none.
And forget those cheapie P95 white dust masks- they are only good for nuisance dusts, eg saw dust, dirt etc.
As far as life expectancy of filters, it all depends on use. My 3M half mask uses the charcoal cartridges as well as snap on pre-filters. The pre-filters grab the large particulate matter to keep the charcoal from getting clogged up quickly. The charcoal provides the chemical vapor filtration. Correct filter selection is vital- the wrong filter can kill.
The worst thing for the life of any mask is improper or no maintenance. After each use, the filters should be removed. The mask itself should be washed in mild detergent and allowed to air dry. After, the mask should go back inside the plastic bag it came in. The filters should be allowed to dry. The pre-filters should be removed and shaken or blown out and replaced if they are heavily contaminated. Most filters also have a place on them to write in the service date. If in doubt, replace them. Filters are relatively inexpensive. I store the filters in a Ziploc bag along with the face piece. Some companies actually provide a nice fabric carrying pouch to put it all in but it is always advisable to put into the plastic bag, then into the storage pouch.

[rob love]

Smelling the paint is one thing...it has an odour that warns you that the filters are saturated and no longer working. Isocyanates have poor warning properties so the problem is you won't know that the filter is no longer purifying the air.

Accepting that a pair of filters is going to be the cost of doing a paint job with paints containing hardeners may be the best solution. While 3M and others have a schedule for the length of life of the filter vs PPM exposure, we in the hobby are not likely to have the equipment required to measure the PPM in the air.

Chris

I agree 110% about that plant on the edge of Brandon. Why they couldn't have built it 20 miles out of town is a puzzle to me. It has the potential to ne day make international headlines.

Just had my fit test about 2 weeks ago by the way.