Emerson Process Management’s Rosemount (www.rosemount.com) Analytical Model WQS water quality monitoring system received a 94 percent accuracy rating by the U.S. Environmental Protection Agency (EPA) Environmental Testing Verification (ETV) program (www.epa.gov/etv/index.html). The system achieved the highest overall system accuracy of 94 percent, while the next nearest competitor scored an average of 85 percent with others as low as 51 percent. In addition, the Emerson system required and received no scheduled operator maintenance during the testing period.

The Rosemount Analytical Model WQS multiparameter system was evaluated along with four other water monitors. The testing was conducted by Battelle in the advanced monitoring systems center. The testing consisted of three stages. Stage I assessed the accuracy of the measurements during nine, four-hour periods against laboratory grab samples, and the WQS achieved 84 percent system accuracy. Stage II reviewed response to changes in water quality by injecting contaminants (nicotine, arsenic trioxide and aldicarb) into the pipe loop. The Model WQS rated at 94 percent system accuracy during 52 days of continuous operation. Stage III consisted of duplicate injections of aldicarb and E. coli. The overall system accuracy score for the Model WQS was 94 percent.

The Model WQS enables plants to establish a baseline for critical measurements including turbidity, conductivity, pH, ORP, free chlorine, monochloramine, dissolved oxygen, ozone and temperature, so that when changes in these measurements are detected, plants are alerted of an event so they can respond accordingly.

To view the EPA’s report on the results of its water quality monitoring systems evaluations, visit www.epa.gov/etv/centers/center1.html.