Any positive pressure powered mask recomendations?

[alexmin]

I have a mask from HD with filters that rated for particles, organic and formaldehyde and still can smell something when I grind micarta.
I checked mask for leaks and it looks like there is no any.

Any way I am start thinking about getting a positive pressure powered mask or hood. Do you guys have any recommendation for me?

Thanks,
Alex

 

[Stacy E. Apelt - Bladesmith]

The molecules that make the odor and the ones that can hurt you are not always the same (but they can be,too).A positive pressure mask will filter particles quite well,but won't stop many organics and things like formaldehyde and cyanide.For these you will still need to wear a filter mask.The other way to go is a positive pressure hood with and OUTSIDE air source.This is what they do in the pharmaceutical industry and in toxic labs.
I use a Trend Air shield hood.

 

[Chris Meyer]

I have a 3m Breathe Easy PAPR system. It has a hard hat with a pressurized face shield and a belt mounted blower and battery pack. It's a little awkward to put on, but once it's on it's quite comfortable. The blower has three filters attached to it and it blows purified air up a hose on your back. The air blows over the top of your head and down the face shield, which cools your head and keeps the lens from fogging. As long as you have the right filters, this system should provide pretty complete protection. The Breathe Easy system is quite expensive, but I bought an older (but unused) unit on eBay for a couple of hundred dollars.

 

[J.Marsillo]

A positive pressure respirator leaks air going out a negitive respirator leaks going in ther are whats called PEL or permissable exposure limits for certain chemicals,a material safety data sheet is good to have but i dont know if they supply them for micarta.
A good way to check for a respiartor leak is to fit it on your face as normal than cover the filters with your hands or plastic bags you shouldnt be able to breath in,or try smell testing with an inert gas like fresh onions,garlic or the like you shouldnt be able to smell anything.Positive pressure respirators are expensive but if you do alot of grinding its worth it you can get chemical pnemonia or worse.
I took my Osha classes about 3 years ago most of that info got wiped out when i picked up knifemaking as a hobby I try to think of positive fit respirators and all that comes up is austinite,1500 deg F, body centered cubic lattice,0-1,s-7 1095,5160....