Transcript Module 4 Control measures & risk reassessment Session structure • Overview • Definition & examples • Actions • Outputs • Challenges • Exercises.

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Module 4 Control measures & risk reassessment
Session structure
• Overview
• Definition & examples
• Actions
• Outputs
• Challenges
• Exercises
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Module 4 Control measures & risk reassessment
Overview
• Document existing and potential control measures
• Assess their effectiveness (validation)
• Recalculate risks accounting for existing control measures
• Prioritize risks
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Module 4 Control measures & risk reassessment
Control measure definition:
Any action or activity that can be used to prevent, eliminate or
reduce to an acceptable level any water safety hazard
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Module 4 Control measures & risk reassessment
Examples – Control measures – low tech
Cover
Well head
Designated
bucket
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Module 4 Control measures & risk reassessment
Examples – Control measures
Automated chlorine dosing system
Source water protected from livestock
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Module 4 Control measures & risk reassessment
Actions
• Identify existing controls
• Document need for new control measures as necessary
Identify
control
measures
Assess
effectiveness
Reassess
risks
Prioritize
risks
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Module 4 Control measures & risk reassessment
Actions continued...
• Assess effectiveness (normal & exceptional circumstances)
Validation
Investigative activity to identify the effectiveness of
control measures. It provides the evidence that
elements of the WSP can effectively meet the water
quality targets.
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Module 4 Control measures & risk reassessment
Actions continued...
• Assess effectiveness (normal & exceptional circumstances)
• Monitoring
• Not in isolation but as part of process chain
• Data from studies / historical records
• Introducing contaminant – testing removal
• Sanitary surveys
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Module 4 Control measures & risk reassessment
Actions continued...
• Reassess risks accounting for effectiveness of control
measures
• Based on long-term average performance
• Highlight where controls are not in place
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Module 4 Control measures & risk reassessment
Actions continued...
• Prioritize all identified risks
• Rank the reassessed risks
• Screen for critical risks
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Module 4 Control measures & risk reassessment
Outputs
Validation of
control
measures
Identification
of control
measures
Prioritization of
risks
Module
4
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Module 4 Control measures & risk reassessment
Challenges
• Uncertainty in prioritizing risks
• Lack of knowledge
• Poor data
• Different approaches = different outcome
• Qualitative versus quantitative
• Assessing effectiveness of certain controls
• Catchment – how to measure/enforce?
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Module 4 Control measures & risk reassessment
Exercise
• In small groups
• Part 1 (5 minutes)
• Match up hazardous events with suitable control
measures
• Identify possible control measures for three hazardous
events
• Part 2 (5 minutes)
• Describe how these control measures can be validated
• Part 3 and 4 (20 minutes)
• Reassess the likelihood and severity by considering the
implementation of control measures and rank the risks
again from highest to lowest
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