Catalogs > Safety Products Catalog > Principles, Standards and Implementation > System Design According to ISO/EN 13849-1:2006
System Design According to ISO/EN 13849-1:2006
| System Design According to ISO/EN 13849-1:2006 |  |
Safety System Architectures (Structures) | |
Mission Time | |
Mean-Time-to-Dangerous Failure (MTTFd) | |
Diagnostic Coverage (DC) | |
Common-Cause Failure (CCF) | |
| Systematic Failure | |
Performance Level (PL) | |
Subsystem Design and Combinations | |
Validation | |
Machine Commissioning | |
Fault Exclusion | |
A full and detailed study of ISO/EN 13849-1:2006 is required before it can be correctly applied. The following is a brief overview:
This standard provides requirements for the design and integration of safety-related parts of control systems, including some software aspects. The standard applies to a safety-related system but can also be applied to the component parts of the system.
This standard also has wide applicability, as it applies to all technologies, including electrical, hydraulic, pneumatic, and mechanical. Although ISO13849-1 is applicable to complex systems, it refers the reader to IEC 62061 and IEC 61508 for complex software embedded systems.
With this standard the safety integrity of a system is classified into 5 PLs (Performance Levels). PLa is the lowest integrity and PLe is the highest integrity. They are evaluated taking the following factors into account:
STRUCTURE – given as designated architectures. These are directly related to the categories.
MTTFd – mean-time-to-dangerous failure
DC – diagnostic coverage
CCF – common cause failures
Behaviour under fault conditions
Software
Systematic failures
Environmental conditions