2 - Schneider Electric CZ, s.r.o.

Presentation
Machine safety
Risk assessment
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Assessment of machinery related risk
European legislation
Machines are sources of potential risk and the Machinery Directive requires
a risk assessment to ensure that any potential risk is reduced to less than
the acceptable risk.
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3
Risk related
to the
potential
hazard
Definition of risk
Severity
of the
potential
harm
Probability of
occurence
Frequency and
duration of
exposure
Possibility of
avoiding or
limiting the
probability of the
occurence of an
event that could
cause harm
Standard EN/ISO 12100 defines risk as follows: risk is the severity multiplied by the
possibility of occurrence.
It defines an iterative process for achieving machine safety, which states that the
risks for each potential hazard can be determined in four stages.
This method provides the basis for the requisite risk reduction.
Risk assessment
> > Risk assessment consists of a series of logic steps which make it possible to
systematically analyse and evaluate machinery-related risks.
>
> Risk assessment is followed, whenever necessary, by a reduction of the risk...
This definition taken from standard EN/ISO 12100 is based on an iterative
process represented in the diagram opposite.
Determination of machine limits
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Risk assessment starts by determining the limits of the machine at all stages
of its life cycle:
> > Transport, assembly, installation
> > Commissioning
> > Use
> > De-commissioning, dismantling
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The use limitations must then be specified:
> > Operating modes
> > Level of training required
> > Space limits (amplitude, movement...)
> > Time limits (life cycle, frequency of maintenance...)
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Start
Determination of
machine limits
Identification
of the potential hazards
Risk estimation
Risk analysis
Risk evaluation
Identification of the potential hazard
If a potential hazard exists, a hazardous phenomenon will cause harm if
measures are not taken.
All the tasks associated with the machine’s life cycle must be identified,
such as:
> > Assembly, transport and installation
> > Adjustment, testing
> > Learning, programming
> > Tool changing
> > Feeding, removal of product from the machine
> > Starting, stopping
> > Emergency Stops, restarting after an unexpected stop
> > Maintenance, cleaning, etc.
Risk evaluation
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Is the machine safe?
End
Yes
10
No
Risk reduction
Logic steps for risk analysis
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