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.
Select potential product choices from the Safety Automation Equipment List.
Evaluate the product for suitability in your specific application.
- Does the product meet all functional needs?
- Are materials of construction compatible with the process chemistry?
- Are environmental ratings sufficient for your environment?
Evaluate the safety integrity of the product.
- Does the product have a 61508 certification with a certification report?
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.
Obtain the Safety Manual for the product.
- Are there any problematic restrictions?
Obtain the failure rate data for the product. Normally the best source of data is a third party FMEDA analysis.
- Was the data analysis technique correct and conservative?
- Is the analysis based on manufacturer’s warranty data?
- Is the data based on mechanical “cycle testing”?
