Risk Reduction - Mitsubishi Electric MELSEC iQ-R Series Safety Manual

*1 SIL is standardized as an index showing the safety level. ( Page 21 SIL)
*2 SIL is standardized as an index showing the safety level. ( Page 22 PL)
*3 The risk is reduced by adding safety measures ( Page 20 Risk reduction).

Risk reduction

As a result of the risk assessment, when the machinery is judged as unsafe, the risk reduction must be performed by adding
safety measures.
The measures for the risk reduction are standardized in ISO12100: 2010 as described below.
Item
Step 1 Risk reduction by inherently safe
design measures
Step 2 Risk reduction by safeguarding and
implementation of complementary
protective measures
Step 3 Risk reduction by information for use
(For details, refer to ISO12100: 2010)
If ensuring the safety of machines by a single safe measure, combine and execute the multiple risk reduction measures until
the machines are safe, according to the procedures above.
3 RISK ASSESSMENT AND SAFETY LEVEL
20
3.1 Risk Assessment
Description
Inherently safe design measures eliminate hazards or reduce the associated risks by a
suitable choice of design features of the machine itself and/or interaction between the exposed
persons and the machine.
Taking into account the intended use and the reasonably foreseeable misuse, appropriately
selected safeguarding and complementary protective measures can be used to reduce risk,
when it is not practicable to eliminate a hazard, or reduce its associated risk sufficiently, using
inherently safe design measures.
Where risks remain despite inherently safe design measures, safeguarding and the adoption
of complementary protective measures, the residual risks shall be identified in the information
for use.