Technical Bulletin No. 0159: Methods for the Continuous Measurement of Dissolved Oxygen in Waste Treatment Processes and Receiving Waters

The attached Technical Bulletin was first issued in 1962, at a time when government agencies, instrument companies, university laboratories, hydropower stations, and industries were putting forth considerable effort toward the development of monitoring stations for the purpose of obtaining continuous data on water quality. One of the problems in connection with these stations was the need for a reliable method for measuring dissolved oxygen continuously.  It appeared then that most of the problems had been solved and that satisfactory instruments continuously recording the dissolved oxygen content of streams were in operation. Improvements in these instruments in respect to simplification and maintenance requirements could be anticipated as well as more accurate measurements under some conditions than those provided by chemical tests. Since that time there has been very substantial growth in the application of such monitoring techniques in the paper industry.