Human Factors

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Human Factors
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Indicators of Human Factors Problems

• Accidents where human error is a cause
• Occupational health reports of mental or physical
  ill-health
• High absenteeism or sickness rates
• High staff turnover levels
• Low level of compliance with hs rules
• Behaviour issues identified in risk assessments
• Complaints from staff about working conditions or
  job-design

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Common Human Failures in Accidents

• Job Factors
• Illogical design of equipment instruments
• Constant disturbances or interruptions
• Missing or unclear instructions
• Poorly maintained equipment
• High workload
• Noisy unpleasant working conditions

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Common Human Failures in Accidents

• Individual Factors
• Low skill competence levels
• Tired staff
• Bored or disheartened staff
• Individual medical problems

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Common Human Failures in Accidents

• Organisation Management Factors
• Poor work planning, leading to high work pressure
• Lack of safety systems and barriers
• Inadequate responses to previous incidents
• Management based on one-way communication
• Deficient co-ordination and responsibilities
• Poor management of health safety
• Poor health safety culture

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Human Failures

• Errors (not intended)
• Slips
• Lapses
• Mistakes
• Violations (deliberate)
• Routine
• Situational
• Exceptional

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Human Failures
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Slips

• Actions-not-as-planned
• Examples
• Performing an action too soon in a procedure
• Carrying out an action with too much or too
  little strength (e.g. over-torquing a bolt)
• Switching the wrong switch
• Moving switch up rather than down
• Carrying out the wrong check on the right item

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Lapses

• Forgetting to carry out an action
• Lose our place in a task
• Can be due to interruptions or distractions
• Example
• Forgetting to fill switchgear with oil?

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Mistakes

• Doing the wrong thing, believing it to be right
• Consist of
• Rule-based
• Knowledge-based

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Routine Violations

• Breaking the rule has become a normal way of
  working within the work group. This can be due
  to
• Desire to cut corners to save time energy
• Perception that rules are too restrictive
• Belief that rules no longer apply
• Lack of enforcement of the rule
• New workers starting a job where routine
  violations are the norm and not realising that
  this is not the correct way of working

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Situational Violations

• Breaking rule is due to pressures from the job
  such as
• being under time pressure
• insufficient staff for the workload
• right equipment not being available
• extreme weather conditions

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Exceptional Violations

• Rarely happen and only then when something has
  gone wrong
• To solve a new problem you feel you need to break
  a rule even though you are aware that you will be
  taking a risk

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Influences on behaviour at Work

• Personality
• Attitude
• Motivation
• Experience
• Aptitude
• Intelligence
• Perception

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Personality

• The study of what makes each of us a distinct
  person
• Some characteristics are shared by all human
  beings
• Each person is different in some respects

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Attitude

• A persons point of view, or their way of looking
  at something
• Influences the way a person reacts in a certain
  situation
• Both good and bad attitudes are contagious

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Attitude Formation

• Attitudes are primarily dependant on
• Early childhood
• Schooling
• Intelligence
• Experiences
• Progress (or the reverse)
• Economics

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Aptitude

• A persons talent for doing something
• Education should give knowledge and help to form
  correct attitudes, while training and practice
  are necessary for aptitude

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Motivation

• That which makes an individual act as they do -
  their reason for doing something
• A drive can be either
• Appetitive - towards something we want
• Aversive - avoiding something unpleasant
• An event that is followed with reward is likely
  to recur (positive reinforcement)
• An event that is followed with punishment is
  likely to desist (negative reinforcement)

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Experience

• With increasing experience we expect more
  competence and an increase in ability to cope
  with situations
• However, there is a tendency to cut corners, as
  shown in the graph

Accident Frequency
Age
Experience
Time
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Intelligence

• There needs to be enough mental stimulation, but
  not too much
• A person with low intelligence may find even a
  routine, mundane job very taxing
• If a person of high intelligence is set a mundane
  task, he will probably employ himself in finding
  new and less arduous, but not necessarily safer,
  ways of completing a task

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Sensory Defects Screening

• Sensory defects increase with age and failing
  health
• We screen out things we are not interested in or
  consider not worth listening to
• We can go into auto-pilot mode, which saves
  effort and allows us to concentrate on other
  things, or think ahead. This is useful, but
  causes many accidents

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Perception of Danger

• Factors involved in perception
• Signals from sensory receptors
• Expected information from memory
• Signals from sensory receptors and memory can be
  misleading, particularly if we are affected by
  stress, alcohol, drugs, fatigue or just
  familiarity

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Perceptual Set

• Also called a mind set
• When we have a problem, immediately we perceive
  not only the problem, but the answer
• Further evidence may become available which sows
  our original perception to be faulty, but we are
  so busy congratulating ourselves on our
  intelligent solution that we fail to see
  alternative causes solutions

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Perceptual Distortion

• Perceptions get distorted
• Things which are to our advantage always tend to
  be more right than those which are to our
  disadvantage

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Errors in Perception Caused by Physical Stressors

• Consider effects of
• fatigue
• overwork
• overtime
• stress from work and home
• Shift work is a major factor
• Our bodies operate best when we have a regular
  routine

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Perception and the Assessment of Risk

• In assessing a risk, there is safety in numbers
• One persons faulty perception of a risk could be
  corrected by another persons clearer perception
• Perception also depends upon knowledge
  experience - a group will have more to contribute