Though this is largely true, I want to discourage people from completely ignoring the good things that IEC 61508 does for the end user.

IEC 61511 is the process industry functional safety standard derived from IEC 61508. In the very first section of IEC 61511 (“Scope”), the standard describes exactly when it should be applied. In addition, the relationship between IEC 61508 and IEC 61511 is clarified in Figure 3 of the 61511 standard. 

IEC 61508 chart

This figure indicates that when an application program is generated using limited variability or fixed program languages, IEC 61511 applies. This is typically the case for an end user. The figure also shows that when the hardware selection is done on the basis of “Prior Use” or on the basis that the hardware is “developed and assessed according to IEC 61508,” the 61511 standard can be used. 

In other words, if an end user does not have a documented and detailed operational event tracking system with sufficient operational experience recorded, which is needed to claim prior use, the end user needs to select the hardware based on IEC 61508 development and assessment. 

So clearly, IEC 61508 still has some impact on the end user. 

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