(a) Continuous emissions monitoring system (CEMS) requirements. When required by this chapter, the owner or operator of any CEMS shall comply with the following.(1) The CEMS must be installed, calibrated, maintained, and operated in accordance with 40 Code of Federal Regulations (CFR) Part 75 or 40 CFR Part 60, as applicable.(2) One CEMS may be shared among units, provided:(A) the exhaust stream of each unit is analyzed separately; and(B) the CEMS meets the applicable certification requirements of paragraph (1) of this subsection for each exhaust stream.(b) Predictive emissions monitoring system (PEMS) requirements. When required by this chapter, the owner or operator of any PEMS shall comply with the following.(1) The owner or operator shall monitor diluent, either oxygen or carbon dioxide:(A) using a CEMS:(i) in accordance with subsection (a) of this section; or(ii) with a similar alternative method approved by the executive director and the United States Environmental Protection Agency; or(B) using a PEMS.(2) Any PEMS for units subject to the requirements of 40 CFR Part 75 must meet the requirements of 40 CFR Part 75, Subpart E, §§75.40 - 75.48.(3) Any PEMS for units not subject to the requirements of 40 CFR Part 75 must meet the requirements of either:(A) 40 CFR Part 75, Subpart E, §§75.40 - 75.48; or(B) §117.8100(b) of this title (relating to Emission Monitoring System Requirements for Industrial, Commercial, and Institutional Sources).