The requirements on safety-related parts of control systems of a machine or device are defined within the framework of DIN EN ISO 13849-1 in categories B, 1, 2, 3, and 4. Category B has the lowest, category 4 the highest requirements on safety engineering.
The categories of DIN EN ISO 13849-1 must not be mixed up with the
Stop categories of EN 60204.
Explanation of the categories:
- B Basic measures (temperature range, EMC,...)
- 1 Category B plus field-proven technology and principles (overdimensioning, positively driven contacts,...)
- 2 Category B plus cyclic system test
- 3 Category B plus detection of single faults, reaching of a safe state in the event of an error
- 4 Category B plus detection of single faults, no risk through multiple faults or detection of multiple faults
Link:
Institute for Occupational Safety and Health of the German Social Accident Insurance (IFA)
