Safety Instrumented Systems

PPG Adopts Cost-Effective SIS

System gives scalability without being cost-prohibitive for a small SIS.

By Jim Montague

Good things come in small packages and apparently in small safety instrumented systems (SIS), too.

For example, PPG Industries recently investigated how to reduce risk in the chloroformates unit at its specialty coatings and materials plant in Barberton, Ohio. The larger plant opened in 1899, while the chloroformates unit has been operating for more than 45 years, and progressed from manual control to pneumatics and relays, and onward to its present PLCs, interlocks. Chloroformates are a key raw material in the production of CR39, an optical lens material used in the manufacture of eyeglasses.

Following its evaluation, PPG decided to adopt an AADvance safety instrumented system from Rockwell Automation because it could provide the risk mitigation needed at reasonable cost—even though the chloroformates unit only has 50 I/O, making it smaller than most SIS installations. "This is a toxic application. We create phosgene, even though we immediately consume what we make,” said Matthew Kinsinger, senior process control engineer, Barberton, PPG Industries.

Read the rest of this article, "Small SIS streamlines performance at PPG," from our sister publication Control Global.