What type of resperator do I need for paints that contain isocyanates and where is a good place to get them. I use dupont bc/cc and I am assuming it contains isocyanates, am I correct? Also, what type of resperator should I use for non-isocyanate paints and for prep work. Thanks for you help.

Jeremy

 

The general rule is that a charcoal respirator is okay if you're using non - isocyanate paint with good ventilation, and a fresh air system for poor ventilation or ANY ventilation with isocyanates.

If I remember right there are previous threads that go into detail about this.

 

<cr>
The isocyanates are actually in the hardener so when spraying BC/CC, you need to be concerned when spraying the CC (clearcoat).

Marc is exactly right. A carbon respirator for non-iso paints. A fresh air respirator for iso paints.

 

Are there isocyanates in the epoxy primers you all recommend to coat bare metal after etching? Or are they mainly found in the hardeners for the clear coat that works like armor protecting the paint job?

Like JeremyD72, I'm trying to understand when I'll likely be using stuff with isocyanates and as such, when I'll need to shell out the cash for a fresh air system.

BTW, I avoided POR-15 for this very reason and just ordered up a bunch of Zero Rust black and POR Metal Ready for the small jobs I'm doing right now.

ROB

 

<cr>
Well Rob, you are attacking the problem with the products I use. Metal Ready and ZeroRust. You can expect good results.

Epoxy primers do not contain isocyanates but there are health concerns (like anyother paint). The good news is, your standard carbon respirator will deal with those issues.

There were a couple of factors I looked at when selecting a respirator. Since I only have one pair of lungs (which I filled with cigarette smoke for too many years), I decided to go the safest route.

The carbon, in the carbon respirators, stops functioning after a period of time. The activated carbon gets used up and stops filtering the chemicals. Isocyanates are odorless so if the respirator stops working, you never know your protection has failed. This is one of reasons OSHA requires a fresh air respirator for isocyanates.

Another reason is that carbon respirators work on a negative air pressure principal. You breath in, creating a negative pressure in the mask, and the outside air is drawn in. If you have a leak in the seal of the mask, unfiltered air will be drawn through the leak. Fresh air respirator always have a positive pressure and if your mask has a leak, the outside air still can't get in.

There is no doubt a fresh air system is expensive. I got luck when it came time to buy. When I retired from a non-autobody field, I had a choice of a retirement gift or the cash. I took the cash and used it to buy a HobyAir fresh air system. I've never been sorry I did.
Dennis

 

I never really realized that epoxys didn't contain isocyanates, but treated them as if they did - anything that chemically hardens is not good to breath. In addition to also smoking for too long, I did do many isocyanate jobs with only a charcoal respirator, and probably shortened my life some because of it. I don't do either one any more (smoke or paint without fresh air) - can't change the past, but feel pretty good at 49.

One bonus of a fresh air system is that the air is pumped to you, you don't have to physically draw it through the charcoal. When doing a strenous overall paint job, that can mean a lot. Less fatigue to cause a run or something, and maybe a little less sweat, and we all know where sweat can end up when painting!

I bought my fresh air system about 10 years ago, (about $600) and don't use it much, but it's always ready when I need it - it's causes me no trouble at all. I keep a charcoal mask around for little jobs, it is a pain to drag that extra hose around, but it's more of a pain to buy those replacement charcoal filters, which I don't have to do nearly as often now! I highly recomend a fresh air system!