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Part 58 (ambient)
1/17/06
Gaseous pollutant
concentration standards (permeation devices or cylinders of compressed gas) used to obtain test
concentrations for CO, SO2, NO, and NO2 must be traceable to
either a National Institute of Standards and Technology (NIST) Traceable Reference
Material (NTRM) or a NIST-certified Gas Manufacturer's Internal Standard (GMIS), certified in
accordance with one of the procedures given in reference 4 of this
appendix. Vendors advertising certification with the procedures provided in
reference 4 of this appendix and distributing gasses as “EPA Protocol Gas” must
participate in the EPA Protocol Gas Verification Program or not use
“EPA” in any form of advertising.