29
Factsheet
Reducing human errors
at work
Henriikka Ratilainen • Vuokko Puro • Virpi Kalakoski
What is a human error?
All workplaces have situations in which work does not proceed as planned, things do not work out as they should,
hazards are prevalent, or accidents occur. If the reasons for
these cannot immediately be found in equipment, systems
or the environment, it is common to refer to a human error.
It has been estimated that a human factor is involved
in up to 80– 90 per cent of accidents. Something may have
gone unnoticed or been forgotten, a situation may have
been incorrectly assessed, or someone might have made a
poor choice of action. These cognitive failures are not the
root cause of things going wrong: there are many kinds of
cognitive failures, and they have many causes.
To err is human
Image: Pekka Rahkonen
Human ability to process information is limited. This is a human characteristic rather than a flaw. Typical physical limitations are easy to see and understand: for instance, humans
cannot throw ten apples into the air and catch them all with
only two hands. However, cognitive capacity limits are not
visible, and they cannot usually be consciously recognized.
Limitations in information processing
• We have a limited ability to perceive the environment
and to notice relevant details.
• We can focus attention on only one thing at a time and
may miss something obvious.
• Switching our focus of attention from one task to another increases performance time and is likely to lead to
errors.
Indiscernible
warnings
Unclearly marked
danger areas
Insufficiently loud
alarms
Poor perception
conditions
Visual obstructions
Insufficient lighting
Auditory or visual
noise
Excessive
workload or
time pressure
Pressure to
do things quickly
No time for breaks
No time to
recover
HUMAN
INFORMATION
PROCESSING
CAPABILITIES AND
LIMITATIONS
Problems
in work flow
Constant
interruptions
Several
simultaneous
tasks
• Our working memory is limited and sensitive to disruptions.
• False memories of details are common.
• We learn slowly and forget rapidly.
• Solving problems and making decisions is demanding
and prone to errors.
• There are many different ways to interpret situations
and that which we perceive.
Working conditions may make us
more prone to errors
Human errors and underlying cognitive failures are often described as the cause of unwanted events. However, rather
than root causes, these failures are more likely to be the
COGNITIVE
INHIMILLISET
FAILURES
VIRHEET
Not noticing essential
Olennaista
asiaa ei
matters
Lack of
information
Insufficient
instructions
Contradictory instructions
Instructions that
are difficult to
understand
Problems in
communication
Messages changing
or becoming distorted
on the way
Messages not
reaching the
appropriate
persons
huomata
Difficulty remembering
Salasana tai koodi on
a password or code
vaikea muistaa
Human
characteristics
and work
demands are
mismatched.
Forgetting work-related
Työhön liittyviä
matters
asioita unohtuu
Pressing the wrong
Painetaan vahingossa
switch by accident
Work does not
progress
Schedules are
delayed
Quality requirements are not met
väärää kytkintä
Hazards
tärkeysjärjestykseen
Injuries
Difficulty prioritizing
Vaikea asettaa asioita
tasks
Not being able to
Ei osata ennakoida
anticipate
a situation
tilannetta
Difficulty
picturing the
Vaikea hahmottaa
consequences
of
päätöksen seurauksia
a decision
Accidents
Factsheet 29 • Reducing human errors at work
Good choices
and decisions
• Sufficient lighting
• Warnings and alarms
that are easy to detect
• Clearly indicated danger
areas
• Reduction of distracting
factors (moving objects,
flashing lights, unnecessary acoustic signals)
• Reduction of auditory
and visual noise
• Orderliness and tidiness
of work environment,
unobstructed routes
• Suitable temperatures
for working
Perceiving
the essential
•
•
•
•
• Ensuring competence through training and induction
• Providing instructions that are clear, non-conflicting and
easily found when needed
• Offering essential information to the right person
at the right time
• Increasing arousal and attention through breaks and
work shift planning
• Creating checklists for critical tasks and encouraging breaks
in demanding situations
Focused
work
Allocating sufficient time
Providing adequate resources
Reducing multitasking
Decreasing the number of interruptions
(telephone calls, messages, disturbing someone who is working)
consequences of working conditions and situations. Cognitive failures occur when conditions, situations or tasks are
too demanding, or when work requirements overwhelm human cognitive abilities.
Many factors temporarily impair the ability to process
information. Anyone can make an error under difficult conditions, regardless of education or experience. Interruptions
and time pressure, for instance, impair our ability to notice
relevant objects and focus our attention. Fatigue and decreased arousal hinder our ability to evaluate and understand
a situation, or to estimate our own performance, and may
lead to poor decisions.
How to reduce human errors
In order to reduce human errors and unwanted events, we
should focus on the factors that led to the situation, rather than on individual employees. If individual persons are
blamed for errors, errors may be covered up, which in turn
means no-one learns from them. As a result, the conditions
and situations that make us more error prone remain unidentified, and we repeat the same errors.
When planning work and the work environment, it is
important to identify and acknowledge human information
processing capabilities and limitations. It is easier to change
work conditions than human characteristics such as the number of our limbs or a limited scope of attention.
Good proactive planning takes into account the type
of cognitive failures that occur at work and the factors that
increase proneness to them. The most effective means of
reducing human errors is to change conditions: to take action
with regard to work environments and the situations, systems, and practices that are likely to lead to cognitive failures
and that increase proneness to errors. Planning work on a
human scale can help reduce human errors and the related
disturbance to work, hazards, and occupational accidents.
A human can cope with even challenging situations when
working conditions make this possible.
Errors can be reduced by identifying the
situations and factors that make us prone
to them
Identify the cognitive failures that occur at your
workplace
• What kinds of failures occur?
• When do failures occur?
Identify the conditions that lead to cognitive failures
• What environmental factors are related to the errors?
• What kinds of situations need solutions?
Reduce the number of human errors
• What changes should be made to working conditions?
• How could the factors that increase proneness to
errors be avoided?
Further information
www.ttl.fi/sujuva
Better work flow, less errors: Decreasing human errors
at work, the SUJUVA project
www.ttl.fi/en
FIOH Topeliuksenkatu 41 a A, FI-00250 Helsinki, tel.+358 30 4741, e-mail: firstname.lastname@ttl.fi, Internet: www.ttl.fi
5/2015