Risk Reduction - Siemens SINUMERIK 840D sl Function Manual

Regulations and standards
2.2 Machine safety in Europe
Figure 2-1
Risks must be reduced by suitably designing and implementing the machine - for instance a
control system or protective measures suitable for the safety-related functions.
If the protective measures involve the use of interlocking or control functions, these must be
designed in accordance with EN ISO 13849-1. For electrical and electronic controls, EN 62061
can be used as an alternative to EN ISO 13849-1. Electronic controls and bus systems must
also comply with EN 61508.
2.2.10

Risk reduction

Risk reduction measures for a machine can be implemented by means of safety-related control
functions in addition to structural measures. To implement these control functions, special
requirements must be taken into account, graded according to the magnitude of the risk. These
are described in EN ISO 13849-1 or, in the case of electrical controllers (particularly
programmable electronics), in EN 61508 or EN 62061. The requirements regarding safety-
related controller components are graded according to the magnitude of the risk and the level
to which the risk needs to be reduced.
EN ISO 13849-1 defines a risk flow chart that instead of categories results in hierarchically
graduated Performance Levels (PL).
IEC/EN 62061 uses "Safety Integrity Level" (SIL) for classification purposes. This is a
quantified measure of the safety-related performance of a controller. The required SIL is also
determined in accordance with the risk assessment principle according to ISO 12100 (EN
26
Iterative process to achieve the required level of safety according to DIN ISO 12100
Function Manual, 12/2017, 6FC5397-4BP40-6BA1
Safety Integrated