Date: Tue, 25 Jan 2011 22:10:44 GMT
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From: "paracelcusbombastusvon**At_Symbol_Here**"

Subject: Re: Do surgical masks = 'respirators'?

The regulatory/respirator issues around an individual piece of equipment o r a process are generally based on the level of exposure of airborne contam inants experienced by the operator.  The short answer is, "it depends. "  Depends on the material being processed, the particle size, the ven tilation in the area, the operating time, work habits, and  other vari ables.  The traditional industrial hygiene approach is to evaluate the exposure by conducting air sampling in the operator's breathing zone and c omparing the results to PELs or TLVs.  Regulations are generally drive n by whether or not a given task exceeds a permissible exposure limit, as o pposed to a rule that says if you operate X machine with material Y, you sh all wear respirator Z.

In some settings, depending on the resources available, it sometimes makes sense to just say, gee, that's pretty dusty.& nbsp; Maybe we should put that mill in a fume hood, or otherwise proceed di rectly to control measures and skip the evaluation step.  It's general ly better to control the source than to fiddle with a respiratory protectio n program, when feasible.


Donald Abramowitz, CIH
Env ironmental Health & Safety Officer
Bryn Mawr College
Bryn Mawr, PA< /span>

I have an associated question to Bradley's that shows my lack of knowl edge: what is/are the respiratory regulatory issues surrounding the operati on of a grinder/mill, specifically one that can generate over 1 kilogram of material?
Thanks in advance, Jim
On Tue, Jan 25, 2011 at 8:53 AM, Norwood, Brad < span dir="ltr"><Brad.Norwood**At_Symbol_Here**> wrote:
As an analytical laboratory, we operate under the Laboratory Standard 1910.1450 of the OSHA regulations.  We have excellent engineering cont rols, and have done monitoring for the the atmosphere contaminants that wou ld be of concern.  We don=E2=80=99t meet the OSHA threshold for any of those.
That being said, we sometimes have to grind samples in knife mills, an d this can generate some dust (though still well below the threshold).  ; Per 1910.134 Appendix D ( nt?p_table=STANDARDS&p_id=9784) we conduct and docum ent training to ensure that our employees have a firm basis upon which to c hoose a dust mask appropriate to their task and comfort.
Now, my toxicology group wants to order surgical masks, and since 1910 .134 defines a "respirator=" as:
Filtering facepiece (dust mask) means a negative pressur e particulate respirator with a filter as an integral part of the facepiece or with the entire facepiece composed of the filtering medium (emph asis added).
In light of the above definition, I am forced to ask:  is a surgi cal mask considered a =E2=80=98respirator=E2=80=99?  Do I now need to document a) that there is no condition which requires use of a respi rator/surgical mask/form of protection in the toxicology section and b) tha t if not, all of the toxicologists are also trained in accordance with Appe ndix D to 1910.134?
Dr. Bradley K. Norwood
Laboratory Director
Arista Laboratories
1941 Reymet Road
Richmond, VA  23237
(804) 271-5572 ext. 307
(804) 641-4641 (cell)
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