Chapter3 Risk Assessment And Safty Level 3 - 1 To; Risk Assessment - Mitsubishi Electric Melsec-QS Series Safety Application Manual

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RISK ASSESSMENT AND SAFTY LEVEL
CHAPTER3 RISK ASSESSMENT AND SAFTY LEVEL
Conforming to EN954-1 and IEC61508, select the risk assessment, safety category, and
SIL to reduce the risk.
This chapter briefly describes the risk assessment, risk reduction and safety category, and
SIL.
For details, refer to each standard.

3.1 Risk Assessment

The risk assessment is to clarify hazards in a machine and assess the degree of the
hazards.
The risk assessment procedure is shown in Figure3.1. This procedure is standardized in
ISO12100 and 14121.
Risk reduction
(
1) Machine analysis,
target equipment
confirmation, and
operation status check
2) Hazard identidication
3) Risk estimation
4) Risk evalution
Safety category
(
SIL (
No
Section 3.1.1
Section 3.1.1)
Figure3.1 Risk assessment procedure
Start
Section 3.2
Section 3.2)
Section 3.3
Section 3.3)
Is the
machinery safe?
Yes
END
3.1 Risk Assessment
Risk assesment
(Referred to ISO12100.)
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