The document discusses the history and evolution of theories around accident causation from early views of accidents being caused by carelessness or acts of God to modern causation models. It outlines Heinrich's domino theory from the 1930s which identified unsafe acts/conditions leading to accidents and injuries. Modern causation models expanded this, identifying additional factors like system defects and operating errors. The document also discusses the Army Systems Model and how safety management can address causation through the seven avenues of error.

1. PLN9 Security Services Pvt. Ltd.
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2. ACCIDENT
CAUSATION
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3. Early Man
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4. Industrial Revolution
Factory managers reasoned that
workers were hurt because —
Number is Up
Carelessness People Error
ACCIDENT
Cost of doing
Act of God Business
PEOPLE PROBLEM
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5. Domino Theory
1932 First Scientific Approach to
Accident/Prevention - H.W. Heinrich.
“Industrial Accident Prevention”
Social Environment Fault of the Unsafe Act
and Ancestry Person or Accident Injury
(Carelessness) Condition
MISTAKES OF PEOPLE
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6. Heinrich’s Theorems
• INJURY - caused by accidents.
• ACCIDENTS - caused by an unsafe act –
injured person or an unsafe condition –
work place.
• UNSAFE ACTS/CONDITIONS - caused by careless
persons or poorly designed or improperly
maintained equipment.
• FAULT OF PERSONS - created by social environment
or acquired by ancestry.
• SOCIAL ENVIRONMENT/ANCESTRY - where and how
a person was raised and educated.
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7. Heinrich’s Theory
Corrective Action Sequence
(The three “E”s)
 Engineering
 Education

Enforcement
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8. Modern
Causation Model
RESULT:
-No damage
OPERATINGERR MISHAP or injury
OR (POSSIBLE)
-Many fatalities
-Major damage
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9. Modern Causation
How accidents are caused &
how to correct those causes.
Parallels Heinrich's to a point.
 Injury is called RESULT, indicating it could involve
damage as well as personal injury
and the result can range from no damage
to the very severe.
 The word MISHAP is used rather than Accident to avoid
the popular misunderstanding that an accident
necessarily involves injury or damage.
 Finally, the term OPERATING ERROR is used instead of
Unsafe Act & Unsafe condition.
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10. Examples
Operating Errors:
 Being in an unsafe position
 Stacking supplies in unstable stacks
 Poor housekeeping
 Removing a guard
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11. Systems Defect
 Revolutionized accident
prevention
 A weakness in the
design or operation of
a system or program
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12. Examples
Systems defects include:
 Improper assignment of responsibility
 Improper climate of motivation
 Inadequate training and education
 Inadequate equipment and supplies
 Improper procedures for the selection &
assignment of personnel
 Improper allocation of funds
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13. Modern
Causation Model RESULT:
-No damage
or injury
SYSTEM OPERATINGER MISHAP
DEFECTS RORS (POSSIBLE)
-Many fatalities
-Major damage
Operating Errors occur because
people make mistakes,
but more importantly,
they occur because of
SYSTEM DEFECTS
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14. Modern Causation Model
Managers design the Systems
COMMAND
ERROR RESULT:
-No damage
or injury
SYSTEM OPERATINGER MISHAP
DEFECTS RORS (POSSIBLE)
-Many fatalities
-Major damage
System defects occur because of
MANAGEMENT / COMMAND ERROR
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15. Safety Program Defect
A defect in some aspect of the safety
program that allows an avoidable error
to exist.
 Ineffective Information Collection
 Weak Causation Analysis
 Poor Countermeasures
 Inadequate Implementation Procedures
 Inadequate Control
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16. Safety Management Error
A weakness in the knowledge or
motivation of the safety manager that
permits a preventable defect in the
safety program to exist.
SAFETY
MANAGEMENT
ERROR
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17. Modern Causation Model
SAFETY SAFETY
COMMAND
MANAGEMENT PROGRAM
ERROR
ERROR DEFECT
SYSTEM OPERATING
MISHAP
DEFECT ERROR
RESULTS
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18. Near-Miss Relationship
 Initial studies show for each disabling injury, there
were 29 minor injuries and 300 close calls/no injury.
 Recent studies indicate for each serious result there
are 59 minor and 600 near-misses.
INITIAL STUDIES RECENT STUDIES
1 SERIOUS 1 SERIOUS
29 MINOR 59 MINOR
300 CLOSE CALL 600 CLOSE CALL
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19. Seven Avenues
There are seven avenues through which we can
initiate countermeasures. None of these areas
overlap. They are:
 Safety management error
 Safety program defect
 Management / Command error
 System defect
 Operating error
 Mishap
 Result
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20. Seven Avenues
Potential countermeasures for each modern
causation approach include:
1
SAFETY 2 3 4 5 6 7
MANAGEMENT
ERROR
TRAINING
EDUCATION
MOTIVATION
TASK DESIGN
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21. Seven Avenues
Potential countermeasures for each modern
causation approach include:
2
1
SAFETY 3 4 5 6 7
PROGRAM
DEFECT
REVISE INFORMATION
COLLECTION
ANALYSIS
IMPLEMENTATION
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22. Seven Avenues
Potential countermeasures for each modern
causation approach include:
3
1 2 COMMAND 4 5 6 7
ERROR
TRAINING
EDUCATION
MOTIVATION
TASK DESIGN
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23. Seven Avenues
Potential countermeasures for each modern
causation approach include:
4
1 2 3 SYSTEM 5 6 7
DEFECT
DESIGN REVISION VIA--
- SOP
- REGULATIONS
- POLICY LETTERS
- STATEMENTS
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24. Seven Avenues
Potential countermeasures for each modern
causation approach include:
5
1 2 3 4 OPERATING 6 7
ERROR
ENGINEERING
TRAINING
MOTIVATION
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25. Seven Avenues
Potential countermeasures for each modern
causation approach include:
6
1 2 3 4 5 7
MISHAP
PROTECTIVE EQUIPMENT
BARRIERS
SEPARATION
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26. Seven Avenues
Potential countermeasures for each modern
causation approach include:
7
1 2 3 4 5 6
RESULT
CONTAINMENT
FIREFIGHTING
RESCUE
EVACUATION
FIRST AID
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27. Army Systems Model
A system is simply a group of interrelated parts which,
when working together as they were designed to do,
accomplish a goal. Using this analogy, an installation or
organization can be viewed as a system.
The elements of the Army Systems Model are:
 Task
 Person
 Training
 Environment
 Materiel
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28. Army Systems Model
TASK
• Communication Control
• Arrangement
• Demands on soldiers
• Time aspects
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29. Army Systems Model
PERSON
Selection Motivation
• Mentally • Positive
• Physically • Negative
• Emotionally • Retention
• Qualified
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30. Army Systems Model
TRAINING
Types Targets Considerations
• Initial • Operator • Quality/Quantity
• Update • Supervisor
• Remedial • Management
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31. Army Systems Model
ENVIRONMENT
•Noise
•Weather
•Facilities
•Lighting
•Ventilation
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32. Army Systems Model
MATERIEL
•Supplies
•Equipment
•Machine Design
•Maintenance
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33. Army Systems Model
SAFETY Army Systems
MANAGEMENT Model RESULT
ERROR • Task
• Training
• Environment
SAFETY • Materiel
PROGRAM • Person MISHAP
DEFECT
COMMAND SYSTEM OPERATING
ERROR DEFECT ERROR
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35. Thank You
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