Epoxy Fume Inhalation And Air Filtration

[Garbonz]

First, the discussion about epoxy vs ester can be well informed by watching several Youtube videos by "Boatworks Today" showing advantages to both project dependent. He also has a pretty good discussion about shop ventilation and a novel ventilation system for cold weather situations.

Second, notwithstanding the interesting seat of the pants discussion about Epoxy hazards and the personal experiences and opinions I can add a couple things from a professional standpoint as an Industrial Hygienist of almost 40 years experience in heavy, medium and light industry. The issue of lighter or heavier than air is a completely irrelevant question in anything but a completely still closed box, which is important for propane or gasoline on a boat, but not in a fabrication shop of any kind.

The Epoxy part A itself is pretty benign, while the Hardner depending on the formulation is a very potent sensitizer with a wide variability of sensitivity amongst the population. Some folks working day after day never show sensitivity, and others become intolerant very quickly. Regardless you do not want to become sensitized. Variations in the products comes from how much free amine evolutes from the hardener which, in turn, is determined by the volatility and polymerization of the amine itself. MFG have, as noted, become very much better at producing a usable product with a minimum of outgassing of the free amine. However, free amine has to be there in order for the epoxy to polymerize and harden so NO epoxy is free from this hazard regardless of MFG claims.

Skin exposure is as or more an issue than inhalation and very strict measure need to be taken to minimize this by PPE including frequent changes of gloves and even suits because the amine will penetrate gloves and suits if it sits on the surface of the PPE. A good organic vapor respirator with frequent cartridge changes is sufficient for all but the highest volume projects, but supplied air or Powered air purifying units (PAPR) are even better.

Ventilation is ALL about getting strong airflow (eg. not the little air fresheners or whatever) and LOTs of activated carbon if not pumped out of the building and replaced with fresh air. A downflow booth like a spray paint system is optimal as it draws the vapors (not fumes) away from the breathing zone of the worker, and makeup air pulled from above. This is not practical for home operations but can be approximated by pulling air from below and close to the area of application and introducing makeup air from the ceiling.

Hope this helps a bit.

[Chotu]

Through trial and error, this is what I have found also. This is extremely accurate.

Originally Posted by Garbonz

First, the discussion about epoxy vs ester can be well informed by watching several Youtube videos by "Boatworks Today" showing advantages to both project dependent. He also has a pretty good discussion about shop ventilation and a novel ventilation system for cold weather situations.

Second, notwithstanding the interesting seat of the pants discussion about Epoxy hazards and the personal experiences and opinions I can add a couple things from a professional standpoint as an Industrial Hygienist of almost 40 years experience in heavy, medium and light industry. The issue of lighter or heavier than air is a completely irrelevant question in anything but a completely still closed box, which is important for propane or gasoline on a boat, but not in a fabrication shop of any kind.

The Epoxy part A itself is pretty benign, while the Hardner depending on the formulation is a very potent sensitizer with a wide variability of sensitivity amongst the population. Some folks working day after day never show sensitivity, and others become intolerant very quickly. Regardless you do not want to become sensitized. Variations in the products comes from how much free amine evolutes from the hardener which, in turn, is determined by the volatility and polymerization of the amine itself. MFG have, as noted, become very much better at producing a usable product with a minimum of outgassing of the free amine. However, free amine has to be there in order for the epoxy to polymerize and harden so NO epoxy is free from this hazard regardless of MFG claims.

Skin exposure is as or more an issue than inhalation and very strict measure need to be taken to minimize this by PPE including frequent changes of gloves and even suits because the amine will penetrate gloves and suits if it sits on the surface of the PPE. A good organic vapor respirator with frequent cartridge changes is sufficient for all but the highest volume projects, but supplied air or Powered air purifying units (PAPR) are even better.

Ventilation is ALL about getting strong airflow (eg. not the little air fresheners or whatever) and LOTs of activated carbon if not pumped out of the building and replaced with fresh air. A downflow booth like a spray paint system is optimal as it draws the vapors (not fumes) away from the breathing zone of the worker, and makeup air pulled from above. This is not practical for home operations but can be approximated by pulling air from below and close to the area of application and introducing makeup air from the ceiling.

Hope this helps a bit.

[Chotu]

Originally Posted by tkalfaoglu

Could any of these compounds' toxicity continue after they dry out?
I mean, could a finished boat make you ill provided you live in it full-time?
If so, perhaps a metal hull is healthier for us!

Very small amounts, of any at all, are present after polymerization.

It’s so insignificant, my extreme epoxy allergy is unaffected living in a 100% Epoxy boat. This assumes proper mixing, of course.

However, the polymer chains are broken and amines are released again any time you machine the cured epoxy. Machined dust is enough to send me to the hospital even on epoxy that has post cured in 110-120F heat for years and years.

So keep that in mind as a route of possible exposure.

[skipmac]

Originally Posted by Chotu

I wish I couldn’t write a book on this, but I can.

There are three types of compounds that are dangerous in epoxy. And these three compounds make up all of epoxy. Lol

First, doesn’t seem to be much of an inhalation issue, but BPA (yes, the one you’re supposed to try to avoid in water bottles because it’s an estrogenic endocrine disruptor) is the resin side of the mix. That’s mostly all it is. Liquid BPA.

Well not quite. Basic epoxy resin is produced by reacting epichlorohydrin with BPA, roughly 5 to 1 so much more epi in the reaction than BPA. However epichlorohydrin is itself extremely toxic. Have not researched this aspect but would not be surprised if the epi is a major contributor to the toxicity of epoxy.

Originally Posted by Chotu

Finally the big one. The bottle marked “hardener” is the aliphatic amine.

Again, mostly correct. Amines based hardeners are the most common and make up the majority of hardeners but there are hardeners made from other chemicals including mercaptans, ketones, anhydrides and others. Most but not all are used for specialty applications for example high or very low temperature curing.

[Dave9111]

Having an air tight shop is fine when you are doing work that doesn't involve fumes. When you are working with fumes, you are really better off having a space that is leaky. Use natural gas heaters mounted high (most dangerous fumes fall to the ground) and heat it when you need to, otherwise keep the temp low, like 40 degrees or don't heat it at all. If you need more ventilation, crack the doors. Since you don't heat it to 60+ degrees the heat bills are minimized. If you are moving, working in 50 degree temps is ok.
I visit a lot of shops in the midwest and more and more of them are heating the shops to only 50-55 degrees or so in the winter. (And these are new buildings)
Sometimes it's not even that warm. But these are shops that are processing a lot of goods with not a lot of people, so the employees wear coats and hats inside during the winter time.
Because of the low interior temps, and the low temp rise over the outside temp, the heat bills are minimized. If you are sitting still doing paperwork etc, 50 degrees can feel cold, so these shops will have interior offices that are heated to 70 or so for the paperwork, telephone calls and meetings, etc. Otherwise its a cool work environment.

[Coltrek]

<<1). If you can, get localized air extraction set up. Vented outside. Have a set of tubes or ducts that are directly over your workstation and pulling air like crazy out of the building. Make them hang from the ceiling so you can move them around and have them pulling where they are needed.

2) provide for continuous air flow from one side of the building to the other. Have open air on one side and large exhaust fans on the other. Don’t worry about filtering. It’ll be expensive and won’t work well. Just keep a constant supply of fresh air coming in and exhaust bad air out. >>


With regards to fresh air, We have a building that is too tight, and that is a problem. The biggest problem most people have is not wanting to pump cold air into their heated building, which is of course a huge problem which I struggled with for years. Finally, a couple years ago, I found an air exchanger/Heat Exchanger made by Fantech, (Supplyhouse.com) the difference in the winter has been incredible. It only seems to be around 10 degrees difference. No more nasal problems in the winter, I wished I had done this decades ago.

[aclmck]

When using these chemicals the gassing drone each particular product is an issue then pence mixed and while being used is another. Then of course while it cures then when sanded

I have worked with most types in confined spaces and while pulling air out of an environment sounds great it doesn’t work as you can’t work successfully work with the amount of wind caused in this activity you need the opposite pump in fresh air from external sources this requires at least a full change per minute so work out the cubic area of your shop wall to wall flor to roof then position fans around with at least the capacity for this or don’t bother as anything less won’t work

The most important thing

Protect skin obvious

Protect mouth nose. Obvious

Protect eyes not so obvious must be air tight (ever tasted an eye drop in your mouth)

Protect ears use plugs


Just my observation and opinion but in forty years never had any workers or myself injured from these epoxies it’s not too expensive to set up but it is essential

Allan