•A calibration gas certified by the vendor not to contain
concentrations of S02, N0x, or total hydrocarbons above 0.1 parts per million (ppm), a concentration of C0 above 1ppm, or a concentration of C02 above 400ppm.
•The auditors are required to
check the zeros
•This has to be on the certification sheet EPA inspectors on site will check ( section 5 of the EPA Acid Rain Program CEMS Field Audit Manual).