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Dr.H
10-10-2005, 12:23 PM
I thought that I would make a respirator tutorial using some info I wrote up last year.

A respirator NOT A DUST MASK is a very important part of our hobby due to the fact we deal with a lot of toxic and harmful fumes in our painting and sanding.
I've done all the HVLP spraying for my companys for years now, not to mention sanding, stripping (paints), glueing, drywall dust. You name it I've had all kind of color snot: black, white, brown, Grey, purple (yea that one takes a while to get use to its from a wood called Purple Heart). Anyway I always use a respirator while painting and a dust mask when I can for sanding.

There are two catagories of respirators:

1) Air Purifying Respirators

A)Elastomeric half and full facepiece respirators (the type we will be using)
http://www.gkjapan.com/gallery/files/1/Face.jpg
B)Filtering Facepiece Particulate Respirators(dust masks which are only good for light sanding)
http://www.gkjapan.com/gallery/files/1/Dust.jpg
C) Powered air purifying systems(most of us will never need or want to spend the money on these).
http://www.gkjapan.com/gallery/files/1/Power.jpg

2)Air Supplied Respirators (Heavy duty life saving chemical protection! I hope none of you will ever need this level of super expensive protection)

A)Self Contained Breathing Apparatus(Respirators whose respirable air source is a cylinder worn by the user, allowing freedom of movement.)
http://www.gkjapan.com/gallery/files/1/Self.jpg

B)Supplied Air Respirators(Respirators deliver respirable air to the user's breathing zone from plant air compressors, low pressure pumps or high pressure cylinders.)
http://www.gkjapan.com/gallery/files/1/Supplied.jpg


For our hobby we will be using Elastomeric half and full facepiece respirators:
http://www.gkjapan.com/gallery/files/1/Respirators.jpg

The full mask covers and protects your whole face so most of us will not need that level of protection. Half masks cover your mouth and nose and they are available in different price ranges from disposible to reusable masks with higher comfort and protection levels.
I use two different Half mask's depending on what I'm doing and I use a 3M 6000 full face mask for HVLP because of paints blowing back in my face and eyes. I love that mask it's really comfortable but overkill for regular spraying.
The 3M and WILLSON models are some of the best and safest respirators.
Just make sure the filter on your masks are organic vapor filters with a Particulate filter on top to trap the larger particles and dust. I should warn that some urethane based paints might have isocyanates in them, which are not effectively removed by organic vapor cartridges.
Here is a 3M's Brochure for their Half and Full facepiece respirators: http://www.gkjapan.com/gallery/misc.php?do=downloadfile&i=414


Here are the two links I use for buying masks but feel free to add your own links. You can aslo find respirators at your local high quality hardware store.

Grainger: http://www.grainger.com/Grainger/searchresults.jsp?QueryString=Respirators&catindx2=Half-Mask&catindx1=Respirators%2C&search_type=keyword

Gemplers: http://www.gemplers.com/a/shop/catsafe.asp?s=2S4DUCAR&UID=200410271649417969380468


OK now that we have talked about the type of respirators lets talk about another question I tend to hear alot of "How do I know when my filters need to be replaced"

As to when you should replace you filters, well there is the old method and the new method. The new method is Niosh approvied so first you have to find out what chemical your using then find their permissible exposure limit in PPM (parts per million )then test how many PPM's are in your room and what the O2 level is because this can change things also. then find the twa (time work average) or the stel (short term exposure limit) Now add this up and the time it takes for your mask to reach ten times the permissible exposure limit is when it needs to be replaced. Confused? Thats NIOSH and OSHA for you.
Now the old method was called Odor Threshold. I'll use Isopropyl Alcohol for an example. When breathing in your mask and you can just start to smell the alcohol, it is around 22ppm and time to replace your filter. While with the other method you would need to know when the mask has passed 10 times 200ppm or 2000ppm.
So while NIOSH no longer approves of this method because of how many variables there are ( sence of smell is different for each person and there may be other chemical in the air making it hard to pick out just one) it is by far the most easy to use.
To make a long answer short:
You have a organic vapor filter that is made of activated carbon so when you can just start to smell any fumes with you mask on it means the carbon is saturated and needs to be replaced. Your Particulate filter should be replaced as needed when you see it gain color and fill with paint. On some filter the particulate filter is built on top of the main filter rather than snaping on top of it, in this case then both filters need to be replaced at the same time.

This covers my basic Respirator tutorial. I will add info in the future if I feel then need and feel free to ask questions or add your own info and experiances.

noiraddict
03-03-2008, 10:00 PM
Time for an update... Manufacturers are now recommending changing cartridges daily or if you can taste/smell chemicals or if there is any damage to the cartridge.

Also any facial hair (at least for half-masks) will interfere with the seal between the face and mask. (It used to be that small mustaches were okay)

Deikin
08-02-2009, 02:04 PM
For simple model work, i.e., the following tasks:

- Sanding
- Glueing
- Airbrushing
- Hand painting

How necessary is a mask? I'm running out of funds quickly setting up my new hobby and I don't think I can really afford a respirator and frequent cartridge replacements. As long as I keep a window open with good airflow, won't that be sufficient?

Joa
08-02-2009, 03:31 PM
For simple model work, i.e., the following tasks:

- Sanding
- Glueing
- Airbrushing
- Hand painting

- Sanding: Always wet sand resin. Period. No "But"'s. Mask not necessary, but it's a bonus. Resins are toxic and you don't want that stuff down your lungs.
- Glueing: Nah .. though some ppl with claim it's for the better. Epoxies ARE toxic after all.
- Airbrushing: If you don't have a booth; Yes.
- Hand painting: If you're using solvent based paints, yes.

Deikin
08-02-2009, 03:43 PM
By 'booth', you mean one that contains an extractor fan I assume?

Joa
08-02-2009, 04:51 PM
yes, of course :bingo:

Deikin
08-02-2009, 05:07 PM
Looks like I need a mask then :why:

Tsunamidelta
08-02-2009, 08:23 PM
Looks like I need a mask then :why:

Well that is if you don't wanna inhale the stuff. some of the paints can really screw ya up! :dizzy:

but, generally.. if you don't have a lot of funds atm. I'd suggest just for a small time just use really good ventilation.

Deikin
08-03-2009, 10:47 AM
Out of interest, I did a brief respirator search on eBay and found this. It seems quite cheap. Opinions?

http://cgi.ebay.co.uk/CHEMICAL-RESPIRATOR-SPRAY-DUST-MASK-GOGGLE-CARTRIDGE-uk_W0QQitemZ170334907703QQcmdZViewItemQQptZUK_Body _Shop_Supplies_Paint?hash=item27a8c06d37&_trksid=p3286.c0.m14

Tsunamidelta
08-03-2009, 10:55 AM
Thing I don't like about that respirator there Deikin.. That fabric.. between you and the mouthpiece that should be the same material as the mask portion to ensure proper seal.. fabric.. doesn't ensure proper seal. I'd save your pennies and buy a really decent mask.. for when you really need it. Till then, just work carefully. You can finish a kit without an airbrush.. you can trust me.. I've done it ^_^ and since your a beginner.. you should try finishing a kit or two first.. before you dump a lot more money on equipment. Hand painting.. properly will produce a very nice kit. just remember that ^_^