Wartsila’s User Group › Forums › General › SCR Diff Press Monitoring This topic contains 0 replies, has 1 voice, and was last updated by cholm 1 month ago. Viewing 1 post (of 1 total) Author Posts December 17, 2018 at 2:36 pm #1943 cholmParticipant Are any of you required to measure emissions module (SCR, Ammonia Slip, OXI) differential as an air permit condition. And if you do not, what emissions are you monitoring continuously such as VOCs etc. Thanks. Author Posts Viewing 1 post (of 1 total) You must be logged in to reply to this topic.