EPA tracks emissions of six principal air pollutants - carbon monoxide, lead, nitrogen oxides, particulate matter, sulfur dioxide, and volatile organic compounds. All have decreased significantly since passage of the Clean Air Act in 1970 - except for nitrogen oxides.
This document describes best practices for the reference architecture for a process control system network and its interfaces to a corporate network. The papers objective is to give the reader an understanding of the techniques utilized to securely connect these networks.
This application note from Delta Controls outlines selection and installation criteria for using admittance probes to monitor the level of powders, liquids and other materials. Dielectric constants of more than 200 materials are included.