exida reported Jan 26 that it's presented Emerson with the 2020 exida Safety Award for its Fisher Digital Isolation triple offset valve (TOV) safety instrumented system (SIS). These awards identify and acknowledge exida-certified products that best display an innovative and practical approach to the Functional Safety Lifecycle.
This digital isolation final element is a TOV developed to meet the needs of users in critical SIS applications and is the first valve assembly to be certified as a whole system. It consists of the Fisher Digital Isolation TOV assembled with the Fisher G or CB actuators and Fisher DVC6200 digital valve positioner.
exida adds it worked with Emerson as it developed the first final element valve assembly to meet the safety organization's rigorous eRAVA certification requirements. They're reported to be the first valve assemblies to meet the design process requirements of Safety Integrity Level (SIL) 3 per IEC 61508.
“We were excited to work with Emerson to accomplish the first certified valve assembly,” says Loren Stewart, evaluating assessor at exida. “By providing a complete SIL solution for valve assemblies, Emerson is reducing unknown variables while helping ensure safety is incorporated, earning them this award.”
Mike Hoyme, product manager for Fisher Rotary Valves, adds: “exida certification assures users that Fisher Digital Isolation TOV SIS will perform as designed in their most demanding SIS applications, and provide an improved probability of failure on demand (PFD) rate. In some cases, the failure rate of the assembly will be up to 50% less than the combination of the same components assembled individually, allowing a plant to significantly extend proof test intervals.”