Safety functions incorporating electronic technology

1.1
This Standard applies to products and component devices where the electronics technology handles the operational logic including the safety features. This Standard applies to the following configurations:

a) safety control function(s) implemented in hardware only; and
b) safety control function(s) implemented in some combinations of hardware and software.

Note: Clauses that are identified by an asterisk define a simplified path for hardware-only designs. For reference, these clauses are listed in Table 2.

1.2
The scope of this Standard includes the sensors and actuators that are associated with the safety control.

1.3
The requirements in this Standard apply to products where failure in either the hardware or software, or any associated devices, can lead to a hazard.

1.4
This Standard prescribes minimum requirements for the documentation necessary to evaluate and confirm that the equipment meets the safety requirements as specified in this Standard.

1.5
This Standard applies to a product identified under a relevant product standard and where the purpose of the product, along with its features and operational role, can be described.

Note: An understanding of the specific end-use environment and any risks associated with the product is essential for this Standard to apply.

1.6
This Standard does not cover general-purpose applications or products where the end-application or the safety requirements for the product are not known or cannot be described, such as for a general- purpose programmable logic controller (PLC).

1.7
In this Standard, shall is used to express a requirement, i.e., a provision that the user is obliged to satisfy in order to comply with the standard; should is used to express a recommendation or that which is advised but not required; and may is used to express an option or that which is permissible within the limits of the Standard.

Notes accompanying clauses do not include requirements or alternative requirements; the purpose of a note accompanying a clause is to separate from the text explanatory or informative material.

Notes to tables and figures are considered part of the table or figure and may be written as requirements.

Annexes are designated normative (mandatory) or informative (non-mandatory) to define their application.