Re: Appropriate Use of Respirator Protection Factors

["TOM_DIXIE" <tom_dixie@email.msn.com>]

The proper use of a respirator protection factors relates the concentration
outside the respirator to the concentration inside, in other words it is a
simple ratio of these two terms.

Lets say you wore a full face respirator inside a bubble suit.  In this
case, the concentration may indeed be lowered but the intent of the
protection factor is to only allow you the maximum protection of one device.
I think the thought on using one factor was;  the wearer is still subject to
the difficulties of wearing the full face or other air purifying respirator
and now the comfort level is comlicated by additional equipment.

Who wears two respirators at the same time anyway?  I think they should be
subject to the lower of the two respirator protection factors because they
are gonna screw it up!

Tom O'Dou
tom_dixie@msn.com


-----Original Message-----
From: Martin_Haas@notes.ymp.gov <Martin_Haas@notes.ymp.gov>
To: Multiple recipients of list <radsafe@romulus.ehs.uiuc.edu>
Date: Wednesday, April 01, 1998 3:32 PM
Subject: Appropriate Use of Respirator Protection Factors


>
>This question relates to the proper interpretation of 10CFR20, Appendix A,
>specifically, the table of allowed protection factors for respirators.
>Part III of the same table notes that for use of any combination of
>air-purifying and atmosphere-supplying respirators,  the protection factor
>should be the same as for, " - - - type and mode of operation as listed
>above".   My interpretation of this is that only a single protection factor
>for combined use of respirators is allowed.  That is, one may not simply
>multiply the protection factor for each of the respirators to obtain the
>net multiplicative effect.   Consequently, the maximum protection factor
>allowed is 10,000, [SCBA, full facepiece, PD] regardless of how respirators
>are combined.
>
>Others have the opinion that this is not the case; that in fact, use of two
>different types of respirators in combination permits multiplying
>protection factors of each in order to obtain a net effective protection
>factor.
>
>Your opinions are welcome either on-line or direct off-line to me at:
>martin_haas@notes.ymp.gov
>
>