Dr. Toru Nakata National Institute of Advanced Science and
Technology, Japan. Nov. 20, 2011 1 Human Error Theory and
Prevention Slide 2 Part I 2 Theory of Human Error Prevention Slide
3 How we make mistakes 1-1 3 Slide 4 Why do we err? 4 Unknown Even
masters of chess sometime commit easy mistakes. A lot of typical
pattern of misconception are found. Four-card problem Monty Hall
problem Horse Trading problem But there is no universal tendency
among them Change the question more productive. Why can we usually
avoid errors? Because we can notice and fix errors before they
break out. Slide 5 Horse Trading Problem Frank sells Sue a horse
for $60. Then he decides he wants it back, but Sue makes him pay
$70 for it. Then Sue changes her mind and buys it back from Frank,
but for $80 (Frank is no dummy). Finally, Frank buys it back from
Sue foryou guessed it$90 (Sue is no dummy, either). At this point,
who comes out ahead?
http://ohiorc.org/for/math/stella/library/problem.aspx?i d=128 5
Slide 6 Typical Example of Human Error Accidents 1-2 6 Slide 7 Case
1: Confusing patients (1999, Japan) 7 Patient A: 74 yrs old. Plan
to be undergone surgery on his heart. Patient B: 84 yrs old. Plan
to be undergone surgery on his lung. Loaded an elevator together,
Mistaken each other, when they brought out of the elevator. 7 Slide
8 But, it was doubtful Some staffs in the operatin room said, Is he
patient A? Different face, vital signs, etc Reconfirm by telephone
to the patient room Have Patient A been moved to the operation
floor? The answer was yes Yoshida Kenko, a famous author, said in
his book Tsure- zure-gusa, The top secret skill of horse riding is
do not ride the horse, when you cannot convince the situation is
perfect. 8 Slide 9 9 Case 2: Bhopal accident (1984, India)
Safeguards are not safe. Because, the management for safety becomes
reluctant. Multiple Safeguards seem highly enough. In actual, all
safeguard did not work enough. Not maintenance for them. Slide 10
What is real meaning of Human Error? 1-3 10 Slide 11 Dont say
error, use term uncertainty 11 Is error wrong? Some errors bring
good results at last. We cannot define error as a bad. What you are
thinking is uncertainty in the work flow. Slide 12 Three ability
for human error prevention 12 AbilityMeaningPower Detectabilty/
Sensitivity against mistakes Can you (or work team) find hidden
mistakes in the front of you? Only this ability can prevent the
accident. Most important ability. Traceability for mistake Can you
specify the cause of the mistake? Greatly reduce the cost to
recovery. Secondary important. Dexterity Can you do your task
without errors? Reduce running cost of the task. But no grantee for
prevention of accident. (Even you are OK, other workers might sow
seeds of accidents) Slide 13 Part 2 13 Solutions for Human Error
Prevention Slide 14 Techniques to ensure human ability 2-1 14 Slide
15 Wake! 1) Fool-proof If the driver sleep, the train will stop
automatically (Fig.1) 2) Fool-Trap If the driver violates speed
limit, he will be injured before he hit somebody else. 15 Fig.2
Bump of the road. Fig. 1 Train console Slide 16 Look your task! 3)
Keep consious about your task. Sing work songs. Cell Production
system 4) Comfortable weather People become thoughless when it is
too hot or cold. 16 Boring line work Cell Production Slide 17 Check
with objectiveness 5) Use body and voice together Pointing and
Calling 6) Check by pair Pair programming in software production.
17 Yes/No check Most easy and unreliable. Check with reporting
number Check with argument Slide 18 This is not end! 7. Prevent
sense of achievement at too early timing Staffs are making a line
when their task already finished. They think they have to keep
their tension until this ceremony. 18 Slide 19 Tool and System to
prevent human errors 2-2 19 Slide 20 Zoning No zoning Zoning for
sanitary 20 Slide 21 Metaphor Tablet representing right to go
forward Remove before flight strap representing the mode of door
safeguard 21 Starbucks Slide 22 Pop-out effect 22 Which is reverse?
Is somebody there? Slide 23 Planning the strategy 2-3 23 Slide 24
Event Tree Analysis (ETA) Mistake files Mistake buttons Business
stops Mistake Email address Other Loose file Reek files Other 24
Ordinary problem Think risk of severe accidents from ordinary
problem. Slide 25 Fault Tree Analysis (FTA) Think the cause of a
particular severe accident by asking why. shipwreck Titanic Lack of
Boats No aids No rescue Iceberg Collision with other ships High sea
25 Paticular accident you have to prevent Slide 26 How to gather
incidents reports easily 26 WhenWhereWhatHowReactionWhoReview
comment 9-2-Mon- 9:00Milling cutter No.3 DrillBrokenRenewalTanakaOK
(Suzuki) 9-4-Wef- 13:00Heater No.5 IntakeDirtyCleanSatoTo be
inspected (Suzuki 9-9-Mon- 10:03 Heater No.5 HolderScrew loosen
TightTanakaOK (Suzuki) Easy to write in. Bring the data into Excel,
and sort them. By sorting, you can find which features (when,
where, .) have got the most reports. That are the most dangerous
features. Slide 27 Slogan: Safety by walking around Hawthorne
effect: Under the situation that somebody may watch your working
scene, you tend to perform better, quicker, and safer. The watcher
is NOT his boss. Without duty, people naturally try to show
themselves as good workers. Walking around. Meet various staffs who
are not bosses nor subordinates in order to encourage them.
Negative Hawthorne effect: Under the situation that your supervisor
is watching you closely, you fell uneasy and tend to refuse the
observation. 27 Open Kitchen. The cook tend to perform better and
more moderate, because somebody may watch him.
