Applicable Performance Specifications PS-12A for Mercury PS-12B for Mercury - Sorbent Trap Procedure You will need Adobe Reader to view some of the files on this page. See EPA’s About PDF page to learn more. Procedure 5 Quality Assurance Requirements For Vapor Phase Mercury Continuous Emissions Monitoring Systems And Sorbent Trap Monitoring Systems Used For Compliance Determination At Stationary Sources (PDF)(7 pp, 39 K)