Respirator/Filter Questions (regarding Micarta/G10)

[REK Knives]

So I found this MSDS on Norplex's Micarta which states "If heated in excess of 300 deg C, products of combustion could include: CO, CO2, phenol and hydrogen bromide gas."

And I found this MSDS for G-10 which states "Carbon dioxide, carbon monoxide, bromine and other hazardous gases may be generated under normal processing conditions."

So in other words, particulate filters alone do not offer adequate protection when grinding these materials if you get them really hot.

I'm trying to look at filter cartridges and which filter ratings are needed for both of these materials. Specifically for the 3m Versaflo (TR-600), under page 13 (here) you can see the available cartridges, all of which have different ratings. I also found this 3m Filter Guide that tells you what the filters need to be rated for which acids/chemicals/gases. It looks like the hydrogen bromide and bromine gases would be filtered out with an OV (organic vapor) cartridge, but the phenol gas (which is the base for formaldehyde??) would need the formaldehyde filter specifically.

Any thoughts/recommendations on this?

* Update: I spoke with Norplex's safety officer and he stated that as long as you keep the micarta under the 300C temps then the Organic Vapor cartridge should be fine.

 

[fitzo]

The resin in Micarta is of the phenolic/formaldehyde variety. When it heat degrades you get formaldehyde and phenol. Phenol is removed by an OV cartridge. Formaldehyde needs a special cartridge.

That said, I don't worry about the formaldehyde so much. It'll be minor. I run an OV/GAS/HEPA on my Versaflo. Costs about $90. It is beneficial to run a pre-filter, too.

 

[N.W. Gean]

What are the chances of reaching nearly 600F while grinding though? I would think you'd have other issues before you hit 500.

 

[fitzo]

I wouldn't think you'd ever approach those temps on a macro level. But what about the micro? Picture one grain of abrasive digging a furrow in a substrate. what is the temp at the point of cut? High enough to degrade nano amounts of phenolic and release minute amounts of phenol and formaldehyde? I dunno, but I'd bet so.
I say this just in analogy thinking about grinding steel. What is the temp of the spark that comes off the blade?

 

[N.W. Gean]

I wouldn't think you'd ever approach those temps on a macro level. But what about the micro? Picture one grain of abrasive digging a furrow in a substrate. what is the temp at the point of cut? High enough to degrade nano amounts of phenolic and release minute amounts of phenol and formaldehyde? I dunno, but I'd bet so.
I say this just in analogy thinking about grinding steel. What is the temp of the spark that comes off the blade?

That's true. Without equipment to measure the temps/amount of fumes coming from the material being ground, we would just be speculating, however. I think the answer here is "how much risk are you willing to take? Do you trust a regular respirator?"

I just don't know enough about particulates to say. I thought I was safe with my 3m half mask and particulate filters

 

[fitzo]

My opinion is that a well-fitted half-face respirator properly fitted (means no facial hair) and with an organic vapor/HEPA particulate filter will protect you adequately across a career of making knives. Provided, of course, that one keeps that respirator bagged when not in use and changes cartridges in an appropriate time frame. I was "safety officer" for my department back in the day for a chemical company and half face/particle/OV met most every need. If you needed more it was either a PAPR or straight to supplied air.

It's the particulate exposure that is going to cause the COPD in the long run. And, if one is going to get cancer at all, one encounters much higher concentrations of carcinogens all through regular daily life. That's more a shake of the genetic dice, IMO.

Doing nothing, of course, is a fool's errand.

 

[Stacy E. Apelt - Bladesmith]

Reading MSDS sheets will cause sleeplessness and paranoia. I also believe repeated exposure to reading them may cause ED. Ask any guy who has read them for 50 years or so and he will tell you that it has affected him .

The data is most useful for destruction situations ... like a fire. It is intended for the people fighting the fire to know what is a possible exposure.

A funny thing is that we are supposed to keep a MSDS sheet on very chemical and material I use. That includes hand soap, cyanide, polish, glue, plating solutions, etc.. OK, I get it, they want to know what is inside the building. BUT, they require it to be in a file stored in the file cabinet. Now, what good will that do a fireman outside the building if it is on fire?????