Chapter 12: ERROR REDUCTION

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Chapter 12 ERROR REDUCTION

• Error reduction is a major goal of ergonomics.
• Goals are Safety, Productivity and Operator
• Satisfaction
• Practices leading to these goals are
• Reduction of physical stress
• Reduction of errors (waste)

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ERROR REDUCTION
An Error is defined as an action other than
desired examples are many like poor design, bad
management practices, bad procedures all these
cannot be completely removed from the system but
can definitely be reduced. Some errors can be
unpredictable or unpreventable
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COSTS AND COSTS REDUCTION
Error Costs can range from a a second lost in
production to the death of an employee. (If
someone misspelled the name.. You lost a
contract) Cost Reduction Pareto chart concept
(Pay attention to problems that contain 80 of
the value
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COSTS AND COSTS REDUCTION
Types of Errors
Slip (not deliberate) Mistakes (Deliberate) OR Omi
ssion ( passive, something not done) Commission
(active, something done)
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COSTS AND COSTS REDUCTION
Types of Errors
Type I Error (alpha risk or producers risk) Type
II Error (beta risk or consumers risk)
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ERRORS ANALYSIS TECHNIQUES
1. Checklists 2. Decision structure tables 3.
Fish Diagram 4. Fault trees (Specific Chain of
Events)
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Error Reduction Guidelines
Error Reduction Techniques are broadly divided
into three main categories 1. Planning 2.
Execution 3. Allow for Errors
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Error Reduction Guidelines
PLANNING
Guideline 1 Get enough information -collect
it -make sure everyone sees it Guideline 2
Ensure information is understood -include
pictures, video, etc.
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Error Reduction Guidelines
Guideline 3 Have proper equipment/ procedures/
skill Equipment -design (incl. lock-out)
maintenance -amount (incl. duplicates)back
ups -arrangement (redundancy)multiple
cal. -maintenance (provide enough budget,
Procedures -computer (required
fields) -human (protocols) Skill -practic
e -include job aids
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Error Reduction Guidelines
Guideline 4 Don't forget -reduce the need
to remember(Chklists) -use memory
aids(calendar, diaries) Guideline 5 Simplify
the task -reduce the number of
steps -improve controls and displays
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Error Reduction Guidelines
EXECUTION
Guideline 6 Allow enough time (Scheduling a
report) Guideline 7 Have sufficient motivation
/ attention -"don't shoot the
messenger" -peer pressure -drug screening
(attention)
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Error Reduction Guidelines
ALLOW FOR ERRORS
Guideline 8 Give immediate feedback on
errors -SPC (closed vs. open loops)
Guideline 9 Improve error detectability -s
ignal to noise ratio (Always tell operator so
next time is OK) Guideline 10 Minimize
consequences of errors -fail-safe overrides
(What if analysis)