Human Factors 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 h&s rules • Behaviour issues identified in risk assessments • Complaints from staff about working conditions or job-design 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 Common Human Failures in Accidents • Individual Factors: – – – – Low skill & competence levels Tired staff Bored or disheartened staff Individual medical problems 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 Human Failures • Errors (not intended) – Slips – Lapses – Mistakes • Violations (deliberate) – Routine – Situational – Exceptional Human Failures 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 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? Mistakes • Doing the wrong thing, believing it to be right • Consist of: – Rule-based – Knowledge-based 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 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 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 Influences on behaviour at Work • • • • • • • Personality Attitude Motivation Experience Aptitude Intelligence Perception 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 Attitude • A person’s 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 Attitude Formation • Attitudes are primarily dependant on: – – – – – – Early childhood Schooling Intelligence Experiences Progress (or the reverse) Economics Aptitude • A person’s talent for doing something • Education should give knowledge and help to form correct attitudes, while training and practice are necessary for aptitude 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) 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 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 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 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 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 Perceptual Distortion • Perceptions get distorted • Things which are to our advantage always tend to be more right than those which are to our disadvantage 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 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
