Moore Industries’ early experience with the EMPHASIS assessment tool in the United Kingdom has helped to refine the company’s approach to building products designed for functional safety and use in the global and UK nuclear industry. The company has been assessed against and used the EMPHASIS tool to achieve approval for four smart instruments with a fifth instrument currently in the approval process.
One of these products is the STA Safety Trip Alarm, which continues to gain adoption in usage in nuclear-licensed facilities in the United Kingdom. Having gone through an in-depth EMPHASIS assessment in 2012 by EDF Energy, the STA has received an integrity level of 10-3 (Probability of Failure on Demand) or SIL 2 capability for safety related applications. This remains the highest level available for “smart” devices that contain and are operated by software or firmware.
Receiving this rigorous qualification from EDF Energy with the STA Safety Trip Alarm reaffirms Moore Industries’ continued commitment to designing and building high quality and highly reliable instrumentation solutions for the nuclear and other industries where safety is paramount.
Applications for legacy upgrades, plant improvements and “resilience” programs are continuing to find new opportunities for the STA. Other products in the Moore Industries FS Functional Safety Series including the SSX and SST family of signal isolators and the SRM Safety Relay Module are also being adopted in other industries for safety related applications.
Moore Industries worked with the Control and Instrumentation Nuclear Industries Forum (CINIF) in the UK on the conceptual development of the EMPHASIS assessment tool for smart instruments intended for use in nuclear safety-critical applications in the UK. Released in 2005, EMPHASIS provides a common framework for determining the suitability of devices in nuclear industries. Earlier designs for process control and safety systems used “good engineering practices and experience” as guidelines. As functional safety awareness grew and software-based products became more complex, standards such as IEC 61508 evolved to create more comprehensive guidelines for implementing safety.
Moore Industries’ compliance with IEC 61508 significantly contributes toward the EMPHASIS assessment for Production Excellence, one of two “legs” used to substantiate safety to the regulator. The second leg involves Independent Confidence Building Measures – measures and techniques such as Static Analysis or Statistical Testing on a product’s source code to prevent potential systemic failures and also taking into account the application demands of the device to be deployed.
The recently released “Vetting Smart Instruments for the Nuclear Industry” white paper details how Moore Industries has designed and configured key products for nuclear safety-critical applications – particularly in the United Kingdom. The paper briefly outlines the steps that Moore Industries took to ensure that these products were designed following strict adherence to the IEC 61508 standard and how using the EMPHASIS process allowed the company to improve design and configure new and existing products for safety in nuclear-related fields.