/community-hubs/fluid-control-pneumatics/b/fluid-control-pneumatics-blog/posts/safety-loop-redundant-solenoids-for-exercise-and-testing-460636102Solenoid valves are often found in safety instrumented functions (SIFs) to release pneumatic pressure holding safety valves open or open depending on the application. Redundancy of these valves enables greater reliability and online proof testing. Inen-USTelligent Community 13