The dirty dozen are the 12 most common human factor precursors to incidents.

1. Human factors in healthcare - The Dirty Dozen
Over the last few decades the aviation industry has lead the way in the study of
human factors. As aircraft have become increasingly safer and more reliable
mechanically it has become more apparent that the humans maintaining and
operating an aircraft can sometimes represent the weakest link in the cause of any
incident.
Human error is both universal and inevitable as it is inherent in our nature as humans
to be prone to these types of error. When errors occur it is natural to think that the
person who made the error is lacking in skill or character, whilst thinking we would
never make such a mistake because we do not share those same deficiencies,
however this thinking means we never learn the lessons we should. Often the most
highly skilled people will make the worst errors because they are assigned the riskiest
tasks.
In high risk industries such as aviation and healthcare small errors can quickly
develop into serious issues that can have drastic and potentially fatal consequences.
An awareness of human factors and how they influence us and our colleagues as well
as using control measures to catch errors before they develop is the best approach for
maintaining safety.
So what are ‘Human Factors?’ There are many definitions available but the UK Health
and Safety Executive defines them as such, “Human factors refer to environmental,
organisational and job factors and human and individual characteristics which
influence behaviour at work in a way which can affect health and safety.” (UKHSE,
2005)
In the late 1980’s, early 1990’s, Gordon Dupont was working with Transport Canada
as an accident investigator and noticed that many of the accident reports he submitted
had the same basic human errors in common. He felt that some of the reports were so
similar he could have changed the details of the incident and submitted the same
report. He went on to identify the 12 most common preconditions for human error and
christened them “The Dirty Dozen”.
The Dirty Dozen
1) Lack of Communication
2) Complacency
3) Lack of Knowledge
4) Distraction
5) Lack of Teamwork
6) Fatigue
7) Lack of Resources
8) Pressure
9) Lack of Assertiveness
10) Stress
11) Lack of Awareness
12) Norms

2. Lack of communication
Generally, only 30% of verbal communication is received
and understood by either party in a conversation.
Normally people will only recall the first and last part of a
conversation and sometimes messages may be unclear
or misunderstood.
Safety Nets
 Ensure the most important information is communicated first and repeated at the
end.
 Use written instructions, guidelines or checklists where available.
 ‘Close the loop’ by repeating back instructions to confirm they were understood.
 Never assume and offer opportunities to ask questions.
Complacency is a feeling of self-satisfaction that occurs
when routine activities have become habituated and
are considered by an individual or organisation to be
easy and safe. When an individual is so used to a task
they think they can complete it without thinking there is
a risk of complacency as People tend to see what they
expect to see.
Complacency
Safety Nets
 Accept that small mistakes can have serious consequences.
 Challenge yourself to find flaws in those habitual tasks.
 Keep yourself physically fit as this helps you stay alert.
 Never delegate a seemingly simple task to someone who is untrained to complete
that task.
 Cross check each other’s work where possible.
 Assume that if it can go wrong it will.

3. Lack of Knowledge
It may seem obvious that lack of knowledge is a major
contributor to errors, but lack of knowledge includes
inexperience or lack of on the job knowledge. People’s
knowledge may become outdated or not relevant to
current practices.
Additionally, an organisation can lack the knowledge it
requires to plan safely if they do not have a safety
culture.
Safety Nets
 Undertake continuing professional development, including learning about human
factors.
 Create opportunities for more experienced staff to share their knowledge with
colleagues.
 Encourage staff to seek help and clarification when they are unsure.
 Refer to checklists, policies and guidelines when they are available.
 Foster a “Safety Culture” where errors can be reported without fear of penalty so
lessons may be learnt.
Our jobs and our lives are full of distractions. When a
distraction shifts our focus away from what we are
doing there is a real risk of us leaving a task incomplete
or omitting a step. Distractions come in all forms such
as our environment, our colleagues or intrinsic factors
such as illness or our home life.
Distraction
Safety Nets
 Ensure you complete a task before assisting or responding to others.
 Signpost or flag tasks which are incomplete.
 Use checklists to ensure all steps have been completed.
 When restarting a task, retrace the last 3 steps.
 Create “Circles of safety” or do not disturb zones around workers engaged in
critical tasks.

4. Lack of Teamwork
Delivering safe healthcare is a team effort and no single
individual can be responsible for a patients safety all of
the time. Staff need to rely on colleagues, other
professionals and sometimes outside agencies as well
as giving their support to others.
Safety Nets
 Ensure the team has a clear objective or mission which everybody agrees with.
 Determine who the team leader is and ensure everyone else knows their role and
responsibilities.
 Maintain clear communication within the team.
 Rehearse and practice rare occurrences as a team.
Fatigue is not just being tired. It is a natural
physiological reaction to prolonged physical or mental
stress and can have a similar effect on performance
as being intoxicated. Humans tend to underestimate
the amount of fatigue they are suffering and
overestimate their ability to cope with it. When we are
suffering fatigue our ability to remember things and
make sound decisions is impaired. We are also more
prone to becoming distracted and losing situational
awareness.
Fatigue
Safety Nets
 Be aware of the symptoms of fatigue and look for them in yourself and your
colleagues.
 Where possible, avoid safety critical tasks when you are most prone to fatigue.
 When this is not possible, try to mobilise other resources to provided added safety
controls.
 Sleep and exercise regularly.
 Ask others to double check your work when you are risk of fatigue.

5. Lack of Resources
A lack of resources can significantly interfere with the
ability to carry out a task safely. Those resources could
be equipment, staff, time, information, appropriate skills,
experience or knowledge. Resources may be available
but outdated or inadequate.
Safety Nets
 Identify early and potential short falls in resources and plan how to manage them
to avoid making decisions ‘on-the-fly’.
 Pool resources and have systems available to share resources.
 Ensure resources are maintained adequately, including human resources.
Urgent demands that are put upon us to complete
tasks create pressure. A certain amount of pressure
is appropriate but excessive pressure can lead to
mistakes or the use of dangerous shortcuts. Some
pressure can be self-induced, but other sources of
pressure can come from managers, patients or our
colleagues.
Pressure
Safety Nets
 If pressure is self-induced it can be self-reduced by prioritising your workload.
 Communicate your concerns to someone who can help alleviate the pressure.
 Ask for help.
 As a last resort, just say no.

6. Lack of Assertiveness
Assertiveness is the ability to express your beliefs,
opinions or needs in a positive and productive manner. It
is not the same as being aggressive and should not lead
to conflict. Assertiveness sits between being passive
where there is a desire to acquiesce to others and being
aggressive where the tendency is for someone to put
their own needs above others. Assertiveness should
strike a balance between both parties’ rights and needs.
Safety Nets
 Refuse to compromise on your standards
 Remain calm and communicate your concern clearly.
 Focus on objective facts and behaviours, not personalities.
 Use graded assertiveness techniques.
Stress can be a mixed blessing. Acute stress can be a
motivation to perform and can have beneficial effects
on our awareness. Acute stress is a result of the
current mental or physical demands that are placed
upon us. Chronic stress can be a result of personal
factors unrelated to the task in hand and it can
exaggerate the effects of acute stress. To little stress
leads to boredom and complacency whilst too much
stress leads to task fixation mistakes or clouded
judgement.
Stress
Safety Nets
 Take 5 minute breaks using relaxation techniques such as deep breathing
exercises.
 Take ‘timeouts’ to look rationally at a problem.
 Determine a rational course of action and follow it. Develop an action plan.
 Discuss the stressors with someone else; they may have a different perspective or
point of view.
 Ask colleagues to monitor your work.

7. Lack of Awareness
Lack of situational awareness is the failure to recognise
the consequences of an action, or the failure to
understand the wider context of an action or event.
Sometimes an excessive focus on one aspect of a task
can lead to a failure to recognise other risks that may be
developing. Often the loss of situational awareness can
occur when other human factors are in play such as
distractions, lack of communication or complacency.
Safety Nets
 Pre-plan possible eventualities before undertaking any safety critical task.
Brainstorm possible unforeseen events.
 Be aware of red flags that may indicate the loss of situational awareness.
 Manage any other human factors that may be present using their safety nets.
 Rehearse the management of unexpected events.
 Constantly ask “What if…?”
Norms are unwritten rules of behaviours that are
followed by a group under the influence of a workplace
culture. As workplace practices develop and change
over time an attitude of “how we do things here” can
develop and normalisations of practice begin to
develop. Norms can be good or bad, safe or
dangerous and are often reinforced through peer
pressure even though they deviate from accepted rules
or procedures. Norms have not been designed to meet
all circumstances and therefore have not been tested
to meet all potential threats.
Norms
Safety Nets
 Always follow the correct procedure, policy or manufacturers instruction.
 If you think you have a better way of doing something raise it so policies can be
discussed and if accepted, amended.
 Be assertive and challenge norms wherever you find them.

8. The dirty dozen is a catchy title but by no means covers all the human factors that
influence our behaviour. Hopefully this article will promote awareness and discussion
about human factors and how they can influence patient safety. Errors are a natural
part of life and the more we can guard ourselves against sure errors the safer we can
provide care to our patients.
Human factors’ training is available and all staff should be encouraged to take part in
such training.
Jon Kyffin

9. UK Health and Safety Executive (2005) Reducing error and influencing behaviour
HMSO