Respirator & acetone (nail polish remover)

See, I haven't learned. Wait for Gip and Triarius to post, and then just add "ditto"!  Makes you look smart without effort!

Bgrigg wrote:

I'm using corrosive as meaning the ability to eat away or be erosive, as opposed to the definition of corrosive meaning destructive. Acetone does not work on oil and grease the same way water does on salt and sugar. Many people assume only the latter definition applies to corrosive. I did not mean corrosive such as an acid would have. Prolonged exposure to acetone does have the ability to cause dermatitis.

Acetone is "lipophilic"—it dissolves lipids, or fat-like substances. That is why it causes dermatitis.

"Corrosive" is generally chemical. "Erosive" is physical, as in breaking a part off. (Of course, on the molecular scale, the distinction blurs…

Actually, the effect acetone has on lipids is analogous to that of water on sugar and salt, in an organic chemistry sort of way. Some lipids return to their original state after solution in acetone and evaporation, similar to the purely ionic solution and redeposition of salt and sugar in water. However, the analogy breaks down with other lipids, which are chemically altered by exposure to acetone.

Technically, your use of "corrosive" may not be correct, but in a literary sense, the meaning is clear.

styrene wrote:

Triarius wrote: And I'd like to add that, terrible as acid burns may be, alkali burns are far worse. My former employer often testified in cement (portland cement is highly alkaline) burn cases, and I was involved in some of them. The pictures are not for the weak of constitution. One of the things that makes alkali solutions so dangerous is that  usually, by the time you realize that you have a problem, it is much too late. By the time they start to hurt, you are already severely "burned."  Ross, As I understand it, alkali solutions have the unique ability to destroy nervous tissue (as well as skin, muscle and fatty tissue), and therefore cause substantially "painless" tissue destruction, while acids are known to physically burn the skin as they "eat" their way through.  Correct me here, but I believe portland cement contains calcium hydroxide, a very powerful base.  I used to insist our laborers wear rubber boots and gloves (and eye protection, too) when pouring concrete. Gip

My understanding is that alkali solutions penetrate all tissue relatively rapidly, compromising everything they encounter—nerves are dead before they can send signals. It is only when the adjacent tissue reacts that pain is felt. The only acid that does this is hydrofluoric, and I believe the molecular mechanism is similar, IIRC.

Portland cement, when combined with water, produces enormous amounts of calcium hydroxide (mineral name: portlandite) and also produces substantial amounts of the alkali cations (mostly sodium, some potassium). The pH of normal plastic portland cement (the binder in concrete) is 13.8 and higher. Actual effective pH of wet concrete exceeds 14.

So don't stop insisting on rubber boots, gloves, knee pads, and eye protection! And at the end of the day, work clothes go into the laundry, they are not worn again until they are washed. Any article of absorptive clothing that comes in contact with plastic (wet) concrete or cement is immediately removed, no exceptions and no exclusions! (Making a construction worker remove his pants in public just once is usually enough to convince everyone…) I recall once a foreman literally cut the pants off a worker, who had refused to take them off (he'd fallen into the concrete that had just been placed.) The worker was dumbfounded, then furious. I stopped him cold when I showed him a picture of a cement burn. He went from furious to tossing his cookies. (Such a picture was part of my field kit—ruined some lunches, but stopped arguements.)

Triarius wrote:

And I'd like to add that, terrible as acid burns may be, alkali burns are far worse. My former employer often testified in cement (portland cement is highly alkaline) burn cases, and I was involved in some of them. The pictures are not for the weak of constitution. One of the things that makes alkali solutions so dangerous is that  usually, by the time you realize that you have a problem, it is much too late. By the time they start to hurt, you are already severely "burned."

Ross,

As I understand it, alkali solutions have the unique ability to destroy nervous tissue (as well as skin, muscle and fatty tissue), and therefore cause substantially "painless" tissue destruction, while acids are known to physically burn the skin as they "eat" their way through.  Correct me here, but I believe portland cement contains calcium hydroxide, a very powerful base.  I used to insist our laborers wear rubber boots and gloves (and eye protection, too) when pouring concrete.

Gip

I'm using corrosive as meaning the ability to eat away or be erosive, as opposed to the definition of corrosive meaning destructive. Acetone does not work on oil and grease the same way water does on salt and sugar.

Many people assume only the latter definition applies to corrosive. I did not mean corrosive such as an acid would have. Prolonged exposure to acetone does have the ability to cause dermatitis.

styrene wrote:

Bgrigg wrote: And how do you think it softens things? It dissolves nail polish, for goodness sake. Of course it's corrosive!  Don't confuse corrosion with oxidation.  Close, Bill, but no cigar.  Dissolution is not the same thing as corrosivity.  Sugar and salt dissolve in water, but even though water is the universal solvent, it is not considered corrosive.  A corrosive, by definition, is any material that has the potential for causing the destruction of (or irreversible damage to) living tissue at the site of contact.  For a material to be corrosive, it must have a pH of less than 2 (acidic) or a pH greater than 12.5 (basic).  Many folks consider strong acids to be the only corrosives, but even dilute solutions of potassium, sodium, or even ammonium hydroxide (strong bases) can be quite corrosive.  There are, of course, other bases as well. You are correct about oxidation.  That is typically the effect a chemical material has on a metal.  Water is a great oxidizer... Gip

Gip is giving you the definition of "corrosion" from the viewpoint of the effect a material has on the human body.

From the viewpoint of the inorganic chemist, there is no precise definition, because the process is poorly understood, and often involves very different systems. For example, the corrosion of metal is generally thought of as oxidation—except that oxygen does not have to be involved, nor are the chemical reactions necessarily those classified as reduction/oxidation reactions. In silicate chemistry, the situation is even more complex and confusing. 

 And I'd like to add that, terrible as acid burns may be, alkali burns are far worse. My former employer often testified in cement (portland cement is highly alkaline) burn cases, and I was involved in some of them. The pictures are not for the weak of constitution.

One of the things that makes alkali solutions so dangerous is that  usually, by the time you realize that you have a problem, it is much too late. By the time they start to hurt, you are already severely "burned." 

Bgrigg wrote:

And how do you think it softens things? It dissolves nail polish, for goodness sake. Of course it's corrosive!  Don't confuse corrosion with oxidation.

Close, Bill, but no cigar.  Dissolution is not the same thing as corrosivity.  Sugar and salt dissolve in water, but even though water is the universal solvent, it is not considered corrosive.  A corrosive, by definition, is any material that has the potential for causing the destruction of (or irreversible damage to) living tissue at the site of contact.  For a material to be corrosive, it must have a pH of less than 2 (acidic) or a pH greater than 12.5 (basic).  Many folks consider strong acids to be the only corrosives, but even dilute solutions of potassium, sodium, or even ammonium hydroxide (strong bases) can be quite corrosive.  There are, of course, other bases as well.

You are correct about oxidation.  That is typically the effect a chemical material has on a metal.  Water is a great oxidizer...

Gip

And how do you think it softens things?

It dissolves nail polish, for goodness sake. Of course it's corrosive! 

Don't confuse corrosion with oxidation. 

hkshooter wrote:

MonsterZero wrote: Acetone is extremely violatile, toxic and corrosive. It is great for cleaning instruments and vessels in a chemistry lab but for modeling purposes it's probably an overkill. I would give up on it altogether and stick to regular lacquer thinner.   Acetone is so reactive it stripped my Badger Anthem airbrush of its chrome plating. The airbrush still works fine but its finish has been stripped.   Acetone is corrosive? News to me, been playing in it and cleaning tools and such with it for years.

Acetone has no effect on common metals, other than to remove grease or oil on the surface. 

MonsterZero wrote:

Acetone is extremely violatile, toxic and corrosive. It is great for cleaning instruments and vessels in a chemistry lab but for modeling purposes it's probably an overkill. I would give up on it altogether and stick to regular lacquer thinner.   Acetone is so reactive it stripped my Badger Anthem airbrush of its chrome plating. The airbrush still works fine but its finish has been stripped.

Acetone is corrosive? News to me, been playing in it and cleaning tools and such with it for years.

I got the picture from this saftey supply site

 http://www.websoft-solutions.net/

but any tool or sftey supply store should have them 

Acetone is extremely violatile, toxic and corrosive. It is great for cleaning instruments and vessels in a chemistry lab but for modeling purposes it's probably an overkill. I would give up on it altogether and stick to regular lacquer thinner.

Acetone is so reactive it stripped my Badger Anthem airbrush of its chrome plating. The airbrush still works fine but its finish has been stripped.

Thanks for the suggestions.

I shaved my beard off last night and I look about 10 years younger...lol.

flaver wrote:

What JViguers  said;   You might need a full face resperator, they cost about $125

can you supply a brand name and model number for me, as I'm also in need of one very badly.

gary

JViguers,

You might want to check out this link to Swanny's Site:

 www.swannysmodels.com/FumeCan.html

His paint fume can might be an answer to your problem.

qmiester wrote:

Couple of suggestions A.  When you put your respirator on, check it for seal - Put your respirator on and cover your filters (inlet valves) and try to breath in, then hold your breath for several seconds.  If you have a good seal, the mask will suck down around your face and stay until you release your breath.  If your mask releases before you release your breath, your mask is not sealed and you need to make adjustments.  Even though in theory once you initially get the mask properly adjusted, it shouldn't leak anymore when you use it, you still need to check the fit everytime you put your mask on.  B.  How old are your filters?  Activated charcoal will start slowly breaking down once it's exposed to air and/or chemicals.  The rate depends upon the chemicals it is exposed to but once it's exposed, it will eventually break down and become useless.  Storing the mask in an airtight bag will alleviate the problem somewhat. (when you're finished using it, wipe the inside of the mask with a soft cloth to remove the moisture (you can end up with some interesting growths in there if you don't & they ain't good for your lungs either) and put it in a large zip lock or sealable plastic bag).  If you've used your respirator for a while and suddenly start smelling the chemicals and or getting the symptoms you refer to - replace the filters immediatly!  And I would recommend replacing the filters every 6 months or so whether you can detect a chemical smell or not.

I agree.  Couldn't have said it any better.  The only point that I differ on--and it's really an opinion--is that if you are taking care of your respirator as qmiester suggested, then the filters should not have to be changed until you begin to smell contaminants inside the mask, or experience difficulty pulling air into the mask when you inhale.  The cartridges on my respirator at work have been in place for over a year...

When cleaning your respirator, check the inhalation and exhalation valves.  Remove the rubber valves from the seats and clean them in warm soap and water.  Wipe off the valve seats to ensure the rubber seals perfectly around the seat.  If the rubber valves are hosed-up (hard, brittle, not seated properly, torn, or missing), or if there's dirt on the valve seat, the respirator is useless as a protective device.

Lastly, stay away from alcohol as a cleaning agent.  It will dry out the silicone in the facepiece and cause the rubber to become brittle.  Mild soap and warm water (not dishwashing detergent, either) is all that's needed.  Oh, and be sure to remove your cartridges before starting any cleaning operations.

And no, you don't need a full-face respirator.  But serious consideration should be given to getting a spray booth, and/or otherwise increasing the amount of available dilution ventilation, particularly if you intend to keep your beard.

Gip

What JViguers  said;

You might need a full face resperator, they cost about $125

Couple of suggestions

A.  When you put your respirator on, check it for seal - Put your respirator on and cover your filters (inlet valves) and try to breath in, then hold your breath for several seconds.  If you have a good seal, the mask will suck down around your face and stay until you release your breath.  If your mask releases before you release your breath, your mask is not sealed and you need to make adjustments.  Even though in theory once you initially get the mask properly adjusted, it shouldn't leak anymore when you use it, you still need to check the fit everytime you put your mask on.

 B.  How old are your filters?  Activated charcoal will start slowly breaking down once it's exposed to air and/or chemicals.  The rate depends upon the chemicals it is exposed to but once it's exposed, it will eventually break down and become useless.  Storing the mask in an airtight bag will alleviate the problem somewhat. (when you're finished using it, wipe the inside of the mask with a soft cloth to remove the moisture (you can end up with some interesting growths in there if you don't & they ain't good for your lungs either) and put it in a large zip lock or sealable plastic bag).  If you've used your respirator for a while and suddenly start smelling the chemicals and or getting the symptoms you refer to - replace the filters immediatly!  And I would recommend replacing the filters every 6 months or so whether you can detect a chemical smell or not. 

I, too have a beard, and there is a workaround. Slather your beard where the respirator contacts your face with KY Jelly. Use a lot of it. Tighten the respirator straps very tight, and test the seal. This is not a good, or long term fix, but it will work in a pinch.

Better yet, get a full face respirator, or invest in a good spraybooth that's vented outside. 

Yea, I have a beard.

Then it sounds like the mask is not sealing sufficiently.

Have you tried tightening it more so it is tighter against the face?

Do you have a beard? If so the mask will never seal properly.

You need cartridges with charcoal in them to filter these types of chemicals.

Are you using a respirator designed to just keep out particulates like dust?

That is what it sounds like.