IEC 61784-3-8:20 21规定了基于IEC 61784 1、IEC 61784-2和IEC 61158类型18和类型23的CPF 8的安全通信层（服务和协议）。它确定了IEC 61784 3中定义的与该安全通信层相关的功能安全通信原则。该安全通信层仅用于在安全设备中实现。 注1不包括电气安全和本质安全方面。电气安全与触电等危险有关。本质安全涉及与潜在爆炸性环境相关的危险。 本文件根据IEC 61508（所有部分）对功能安全的要求，定义了使用现场总线技术在分布式网络中的参与者之间传输安全相关消息的机制。这些机构可用于各种工业应用，例如过程控制、制造自动化和机械。本文件为合规设备和系统的开发人员和评估人员提供了指南。

IEC 61784-3-8:2021 specifies a safety communication layer (services and protocol) based on CPF 8 of IEC 61784 1, IEC 61784-2 and IEC 61158 Type 18 and Type 23. It identifies the principles for functional safety communications defined in IEC 61784 3 that are relevant for this safety communication layer. This safety communication layer is intended for implementation in safety devices only.
NOTE 1 It does not cover electrical safety and intrinsic safety aspects. Electrical safety relates to hazards such as electrical shock. Intrinsic safety relates to hazards associated with potentially explosive atmospheres.
This document defines mechanisms for the transmission of safety-relevant messages among participants within a distributed network using fieldbus technology in accordance with the requirements of IEC 61508 (all parts) for functional safety. These mechanisms may be used in various industrial applications such as process control, manufacturing automation and machinery. This document provides guidelines for both developers and assessors of compliant devices and systems.