A safety-function is a formally specified function that a safety-related system must execute to achieve or maintain a safe state upon detection of a specific hazard or hazardous event. It is defined by four parameters: (1) the hazard it addresses, (2) the safe state it targets, (3) its required performance level (e.g., SIL rating or Performance Level), and (4) its required response time. A safety-function persists through its specification in safety requirements documents, its implementation in safety-related control systems (sensors, logic solvers, final elements), and its validation against IEC 61508 or ISO 13849 standards. [formal: safety_function | substrate: behavior | horizon: a life | explicit: yes | epoch: 0.01]
Accepted ontology entry
safety-function
A safety-function is a formally specified function that a safety-related system must execute to achieve or maintain a safe state upon detection of a specific hazard or hazardous event. It is defined by four parameters: (1) the hazard it ad…
Definition
Why it is in scope
A human-made concept in functional safety engineering designating a function that must be executed by a safety-related system (such as a safety-instrumented-system) to achieve or maintain a safe state when a specified hazard or hazardous event occurs. Built through safety engineering standards (IEC 61508, ISO 13849) and embedded in safety requirements specifications, system architecture, and validation testing protocols.
Names and aliases
- safety-functionen · CANONICAL
Relations from this entry
- cms8olo5701ld73fkxedp404qSERVES →
A safety-function is built and maintained for the sake of process-safety. Its designed purpose is to execute a specific action that maintains or brings a process into a safe state when dangerous conditions arise. Law 8d: the servant (safety-function) points at the master (process-safety).
Relations to this entry
- cms8shivi01zr73fk3j4z0tw7← INSTANCE_OF
safety-instrumented-function IS a specific kind of safety-function: it is the instrumented implementation of the abstract safety function concept. Per Law 9: a competent speaker calls a safety-instrumented-function 'a safety function.' safety-function (epoch 0) is the older, more general concept; safety-instrumented-function (epoch 0.01, per IEC standards) is the specific implementation. Files against the nearest kind.
Record identity
- Created
- Jul 31, 2026, 9:31 AM UTC
- Content hash
- 6a9a78ddb286e06cd203339543de129f1c886814cceb359cc1edfda0b9299f89