IEC 61784-3-18:2011+A1:2016 specifies a safety communication layer (services and protocol) based on CPF 18 of IEC 61784-2 and IEC 61158 Type 22. It identifies the principles for functional safety communications defined in IEC 61784-3 that are relevant for this safety communication layer. THIS CONSOLIDATED VERSION CONSISTS OF THE FIRST EDITION (2011) AND ITS AMENDMENT 1 (2016). THEREFORE, NO NEED TO ORDER AMENDMENT IN ADDITION TO THIS PUBLICATION.