Heinrich Deconstructed
(and reconstructed!)
A Safety Revolution in Progress
Presented at CSSE 2012
Professional Development Conference, Niagara Falls, Canada
September 11, 2012
Wayne Pardy - Quality Plus Inc.
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Some brief historical context


Heinrich’s Causation Theory: the 88-10-2 Ratio
Heinrich professed that among the direct and
proximate causes of industrial accidents:
•88% are unsafe acts of persons.
•10% are unsafe mechanical or physical conditions.
•2% are unpreventable (i.e. acts of God).
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Krause took this further

“In the majority of cases – from 80% to
95% - accidents are caused by unsafe
behavior. This statement emphatically
does not mean that the injury is the
employees fault”.
Source: “The Behavior-Based Safety Process” Krause, Hidley & Hudson
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Dupont went even further still
10 year study across all DuPont sites
 96% of injuries resulted from ‘unsafe acts”
and “poor work practices”

Dupont, 1986
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And Difford has gone even further still
“Whilst generally supportive of Heinrich
(1941), Difford presents the case to revise
Heinrich’s finding that 88% of accidents
result from unsafe acts and proceeds to
logically adjust that figure to 98%”
Keith Scott, Chairman International Institute of Risk and Safety Management
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Are Difford and Heinrich wrong?
While there have been many critics of
Heinrich, it is worthwhile to note that
“Heinrich's 88% has been dismissed and
criticized, but not refuted”
Difford on LinkedIn (EHSQ Elite)
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So What?
According to Manuele, “Heinrich’s. . . ratios have had the
greatest impact on the practice of safety” – How?

“It has also done the most harm” – Why?

“Since it promotes preventive efforts being focused on
the worker, rather than on the operating system”.
Heinrich Revisited: Truisms or Myths
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Borderline unethical?
A Manuele colleague who is disturbed by safety
professionals who reference Heinrich premises as fact,
says, “It is borderline unethical on their part.”
Source: http://www.asse.org/professionalsafety/pastissues/056/10/052_061_F2Manuele_1011Z.pdf
.
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Manuele’s bottom line
“The premise discussed here (unsafe
acts of workers) are the principle causes
of occupational accidents are wrongly
based and cannot be sustained by safety
practitioners”.
Source: http://www.asse.org/professionalsafety/pastissues/056/10/052_061_F2Manuele_1011Z.pdf
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Manuele’s call to safety professionals



Stop using and promoting these premises
Dispel these premises in presentations, writings
and discussions;
Apply current methods that look beyond
Heinrich’s myths to determine true causal factors
of incidents.
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Enter Paul Difford and “Redressing the
Balance (2011)
Accident causation
“There are many who believe that
management or organizational failures are
the root of all accidents”.
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Redressing the Balance, 2011





Management failures cause all accidents - Myth
Reason’s Swiss Cheese Model and Bird’s management
failure model - Disproved
The ‘so called’ Organization Accident - Myth
Petersen’s multiple causation theory - Disproved
Heinrich’s Accident Causation Theory - Empirically and
logically valid with modification
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“Redressing the Balance” supported by:
Ten year study about current models of
causation
 114 books
 56 publications and papers
 18 UK, EU and USA case studies, and
 10 web site references

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The management failure movement
Petersen, Bird, Reason, et. al.
 “Compelled into absurdity and the categoric
denial that workers have either right, inclination
or opportunity to exercise free-will in the
workplace”
 “For them, error and violation are always the
consequence of managerial or organizational
failings”
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A perspective on Heinrich’s 88%
“A common, if not ‘convenient’ misinterpretation
is that this in some way equates to a theory that
blames front-line workers, but that is not the
case
Source: Difford, 1998
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HSE
(UK - 2002:1)
“The nature of accident causation has changed with
engineering failures no longer being a major feature in
many accidents”
“It is now largely behavioral with human failings being a
significant part of the causes of most accidents. Of
these, knowingly deviating from approved work practices
represents a large proportion of incidents involving some
form of human error. This form of human error is often
termed ‘violation’.”
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Interesting!

Where is the body of literature, empirical
data and research that supports multiple
causation theory, management failure and
organizational accident perspectives?

We’re still waiting.
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Some perspective - What is a Causal
Factor? (in my world)
“Mistakes or failures that, if corrected,
could have prevented the incident from
occurring or would have significantly
mitigated its consequences”
Source: TapRoot®: Changing the Way the
World Solves Problems. P. 77
By Mark Paradies and Linda Unger
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What does a causal factor look
like?
Was this a mistake made, or was
something done wrong, or
 What equipment failed or did not work as
intended?

NOTE! “Wrong” does not indicate blame. It
is simply a statement of fact.
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Causation considered



Why do so many automatically default to the
organization or system when an accident happens?
Why is it not the person’s accident?
Why is it someone else’s accident?
These questions have no notion or reference to blame in
them. . . therefore there should be no notion or reference
of blame in your answer.
Source: Difford. P. 175
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Management or Organizational Failures?
Workers were asked who they thought was best placed to
reduce the chance of them having an accident?

Themselves – 70%

Other workers, Supervisors Management & Unions (30%)
Are those 70% of respondents out to lunch?
Source: Hale and Perusse (1977) citing McKenna
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HSE (UK) 2002 & 2004 studies


Violations were linked to between 70%-90% of
accidents (2002)
Problems stemming more from known violations
than from lack of knowledge (2004)
“A Deadly Maintenance. . . 30% of the 739
deaths to which he refers could not possibly
have been rooted deeper in management” (1985)
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Management Failure School of Philosophy
Based almost exclusively on the belief that a man is never the cause
of his own behavior, i.e. that a man is never responsible for his own
actions.
On the one hand, Petersen stated that management ‘invariably’
causes all accidents. . . Yet Petersen himself was even forced to
concede:
“a painfully obvious and simple truth. . people, not things cause
accidents”
(Petersen 1979:15)
Source: Difford, p. 161
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Bird & Reason
“ Moved a million miles away from Heinrich’s
findings in order to claim (based on their own subjective
re-labeling of things) that the cause of a man’s
behavior, without exception, is due to
management or organizational failures”
Difford. . . P. 74
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Difford
“If they are right that only management can
cause an accident, then only management
can prevent one since. . .
. . . with no opportunity for sharp-end man
to cause one, logic dictates that he cannot
possibly have any opportunity to avert one
either”.
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I am not an animal!
Management failure theory: “Presumes a
workplace full of mindless automatons devoid of any free
will. . . such that, regardless of what anyone does, it will
always be someone else’s fault (i.e. attributable,
ultimately and without exception, to management or the
organization”.)
Source: Difford. P. 101
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Can you or I control ourselves?
For Difford and his supporters, “the notions of so-called
organization accident (Reason, 2004) and the
organizational model of human error are pure fiction”.
“They reply largely, if not exclusively, on the belief that
workers (you and I) have neither right, inclination, ability
or opportunity to exercise free will.”
Difford, P. 103
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Difford’s 10 year study

At a stretch, error is behavior

. . . But, it is not a system driven phenomenon insofar as
it has not been found to be caused by the environment in
the academic, epidemiological or multi-factorial sense.

More often than not, it results from an individual’s
assessment of the environment’s ability to either prevent
or support the behavior that they are contemplating
(Bogner, 2004)
(Ajzan, 1991)
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How many dominos do we need?
If Bird genuinely believed that management failures always cause
accidents then there is no reason for his domino sequence to look
anything other than the depiction below:
Management failures
Accidents
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So what are the challenges?
“Academics have confused themselves and each other
over causation. . . That aside, the MCT (multiple
causation theory) approach is extremely attractive to
regulators and so it is not surprising that they force the
philosophy into the H&S community.
“For now, they need to realize that people, not things,
cause accidents and that something is seriously out of
balance”.
Wayne Pardy - Quality Plus Inc.
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Why Difford’s work is unsettling for many in the
safety community:


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It requires a questioning of the widely held belief that
management or organizational failures are the root
causes of most, if not all, accidents.
“ There is, in fact, no such thing as an organization
accident” (it being an academically miscalculated
invention).”
For some, all their rhetoric and money making ideas and
programs are seriously challenged
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Challenges to the safety community



Many have put too much on the line to even
read Difford.
It would mean a change in approach to a lifetime
of what some safety practitioners have written
and practiced.
Many have said so much in support of
management system failure theory of accidents,
MCT and organizational accidents that they are
now not able to ‘save face’ if they in any way
accept Difford’s work/conclusions.
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Will anyone listen?
“The extent of the programming is such
that many will be unable to change”.
Source: Difford in email to W. Pardy
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So where does this leave us?

We have 2 very distinct camps, both supported by their
research/perspectives and theories

They cannot co-exist
Management failures, organizational accidents and multiplecausation theories of causation
vs.
Management cannot possibly cause all accident approach
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What to believe and why?
Acts of God aside, (or more correctly, the unpredictable
and uncontrollable consequence of natural phenomena) human
behavior, irrefutably, will be the proximate
cause of any preventable accident.
OR
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Management or organizational failures
cause all accidents
What to do?
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You make up your own mind after considering the
evidence (I’m simply a messenger).
Consider:
 Redressing
the Balance (Difford)
 Heinrich Revisited: Truisms or Myths
As well as the following
The following links will be helpful:
http://www.nsc.org/safetyhealth/Pages/Examiningthefoundation1011.aspx#.UDFonPVHCVo
http://www.asse.org/professionalsafety/pastissues/056/10/052_061_F2Manuele_1011Z.pdf
http://www.neucom.eu.com/documents/REPLYTOASSEMANUELE.pdf
http://www.neucom.eu.com
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Final thought

Don’t be bullied by those ‘experts’ who have a great deal
to lose by maintaining their ‘theory’ of accident causation
(academics, consultants, regulators, etc.)


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Read and absorb all you can and then decide based on
the logic, rationale and argument of your own research.
Don’t dismiss Difford outright, as some have done. Fear
won’t progress our efforts in causation.
Do your homework, assess the evidence, and make up
your own mind.
Wayne Pardy - Quality Plus Inc.
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So what? Why should I care?

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It will help us determine effective prevention strategies
It will put our resources in the right place, for the right
reasons
It’s about people – let’s emphasize what’s important
Alternatively, we’ll continue to be polarized
We’ll have no accepted body of knowledge on causation
Let’s get our own house in order
Safety is still in growth and pursuing maturity.
How about you. . . What will you do?
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