The following requirements apply for the development of this document:

Safety communication suitable for safety integrity level up to SIL 4 (see the IEC 61508 series) and PL e (see ISO 138491).

Combination of SIL 1 to 4 devices according to this document as well as non-safety devices on one communication network.

Implementation of the safety transmission protocol is restricted to the safety layer.

The safety-relevant time-out monitoring is implemented in the safety layer.

Safety communication meet the requirements of IEC 617843.

[RQ5.1] This document is intended for implementation in safety devices exclusively. Exceptions (e.g. for debugging, simulation, testing, and commissioning) shall be discussed with a notified body.