A Long-Term Field Evaluation of Mercury (Hg) Continuous Emission Monitoring Systems (pdf, 142pp., 908kB) is available from US EPA. The report evaluates the ability of mercury continuous emissions monitoring systems (CEMS) to meet performance specifications recently promulgated in 40 CFR Part 75 and Performance Specification 12A (40 CFR Part 60). Included are summaries of certification test results from two relative accuracy test programs, as well as other information collected from November 2004 through September 2005.