Careful selection of equipment used in automation safety is important. The quality, safety integrity and suitability for application must be understood.
To make this task easier, the Safety Automation Equipment List provides guidance on the tasks that need to be performed and a comprehensive list of products that have been third party evaluated per one of the recognized evaluation techniques as shown below.
Step 3a: If no application suitable 61508 certified product is available, then prior use justification must be made per IEC 61511. A third party “Proven In Use” report or a third party FMEDA analysis will be valuable as part of the justification.