Let’s band together for
afety, uality, peed of Execution
A ship is safe in
harbor, but that's not
what ships are for
1
The Problem with Poka-Yoke
We’re all in the same boat -
2
Hopefully, not this one !
Improvement? Bah, Hum Bug !!
Sustain the Gain
Our objective:
Take away
and go implement it!
And … we’ll ask for one at end of the presentation.
5
Where in the World are Poka-yoke?
They exist in the world around us…
(they’re out there)
Where in the World are Poka-yoke?
Let’s brainstorm!
1st,
some…
Classic Brainstorming Ground Rules
•
•
•
•
•
•
•
Everyone participates
No judgments or teasing
No body language
Play off each others ideas
Write so others can see
Promote a “Can do, won’t fail” attitude
Start with “Open” questions…
– “What would we do to fix?”
– “What are some ways we could…”
– “If anything were possible, what…”
Now, where have you seen one?
• Describe a poka-yoke you have experienced…
(a mistake-proofing thingy)
What Are Guidelines for Poka-Yoke ?
In general, the approach of Poka-Yoke should meet
the following guidelines:
 Based on
and obvious to the
person involved in the process
 It
at the root cause
BTW: Don’t Do Fake Poka-Yoke!
Almost !!
Almost !!
Almost !!
Almost !!
Almost !!
(Sure looks like a
trash can …)
Almost !!
Cheaper
than a
plumber!
Almost !!
Easier to
make a
sign,
then call
tech
support!
Almost !!
Do …
Careful
pedestrians
need to
stop??
Almost !!
2
Parts
to this
one…
Notice how
far away sign
is from
hospital bed
Almost !!
“falls
program…”
Really ??!??!!
Almost !!
So many signs!
Maybe the pit
fell in the void
after catching
fire??
Almost !!
Another!
Almost !!
At least they
had a little fun
with this one!
Almost !!
Who keeps leaving the coffee pot on?
Hint: the cleaning crew …
Almost !!
Why did you “pop” open the trunk to gas up?
Almost !!
Which one turns on the fan?
Gold tassel for light (golden rays of sunshine??…)
Almost !!
Almost !!
Where’s the flusher?
Almost !!
Where’s the flusher?
Almost !!
How do you turn on the shower?
Almost !!
towards their goals, but there are two big ones to look out for:
Remove And Combine Functions
First, most websites have way too many things that are clickable. Try to
eliminate unnecessary functionality, and if you can’t get rid of it, try
combining it with something else if it makes sense to do so. For example,
many shows will combine temperature and water pressure into 1 knob. This
eliminates the user’s ability to create a “hot-but-low-pressure” shower, but
most people wouldn’t want that anyway. Minimizing functionality and
clickable elements might seem obvious, but if your website is old and has
suffered from some feature creep, it might be time to do some spring
cleaning with a fresh perspective.
Avoid Failure States
Second, don’t allow the user to do things that could result in a failure state.
I’ve seen way too many forms that let me type in lots of invalid input before
submitting. It’s only after I click the button I find out that “usernames must
be 8 characters long” or that I mistyped my email address or something else
stupid (can you sense the frustration?).
http://blog.teamtreehouse.com/poka-yoke-the-quest-for-mistake-proof-designs
What is the Purpose of Poka-yoke?
Prevent a foolish action through 3 functions:
HUT DOWN a process, machine or operation
ONTROL a process, machine or operation
ARN that a defect (is about to occur or) has
occurred
Why don’t you want to Improve ?
• Stuck in a rut!
– (with associated ‘work-arounds’)
• Comfortable with your problems/errors
• Not feeling enough pain to do something
different
• Waiting for something to happen
Maybe, you just don’t know what to look for…
Top Causes of Errors
• Processing omissions: leaving out one or
more process steps
• Processing errors: process operation not
performed according to the standard
• Error in setting up: using wrong tooling or
incorrect setting/ adjustment
• Missing parts: not all parts are included in
assembly/ process
• Improper part/ item: wrong part installed in
assembly
Top Causes of Errors
• Processing wrong work piece: wrong part
machined/ processed
• Operations errors: incorrect revision or
specification sheet
• Errors in equipment, maintenance or repair:
Defects caused by incorrect repairs or
component replacement
• Error in preparation of inspection equipment,
fixtures or tools: Damaged inspection tooling;
poorly designed fixtures or wrong tools; mismeasurement
Why a “Poka-Yoke” Hierarchy?
Most Desired
Full Automation
Fail-Proof
Simplification
Training
Awareness
Least Desired
37
• No Manual Intervention
• Impossible to Fail
The process is
changed to be
less dependent
upon people
• Eliminate Activity
• Certification and Audits
• Notification
So you don’t have to “fix” the problem again!
Behavior
typically reverts
back
Why a “Poka-Yoke” Hierarchy?
Most Desired
Full Automation
Fail-Proof
Simplification
Training
Awareness
Least Desired
38
• No Manual Intervention
• Impossible to Fail
The process is
changed to be
less dependent
upon people
• Eliminate Activity
• Certification and Audits
• Notification
So you don’t have to “fix” the problem again!
Behavior
typically reverts
back
Why a “Poka-Yoke” Hierarchy?
Most Desired
Full Automation
Fail-Proof
Simplification
Training
Awareness
Least Desired
39
• No Manual Intervention
• Impossible to Fail
The process is
changed to be
less dependent
upon people
• Eliminate Activity
• Certification and Audits
• Notification
So you don’t have to “fix” the problem again!
Behavior
typically reverts
back
2 states for Poka-Yoke
Occurrence –
is the situation
(occurs)
Detection –
the situation
[“Shutout” is best]
at the point of mistake
Occurrence Poka-Yoke
Occurrence is the situation
(occurs),
but … sometimes after the fact also.
• An example would be a buzzer or warning light.
– a fire alarm is a type of “Occurrence ” Poka-Yoke.
Occurrence Poka-Yoke
Occurrence is the situation as it happens (occurs),
but … sometimes after the fact also.
• An example would be a buzzer or warning light.
– a fire alarm is a type of “Occurrence ” Poka-Yoke.
In general,
Occurrence situations that merit ‘Poka-Yoke’ can happen if
there is a chance that:
• the required action is not performed
• the required action is performed incorrectly
• the complexity of process could lead to defects
• information required to perform an action is not understood
or easily misinterpreted
Occurrence -example
• Computer Start-up Routines
– [password/log-in/pin etc]
• Computer Shut-down Routines
• [series of low battery warnings/ actions taken]
Occurrence
For this situation, it’s important to follow these
guidelines:
• At assembly, make sure that the wrong parts do
not join together (think of Lego pieces that
cannot join because they are not from the same
Lego set)
• Use of 100% prevention devices such as
contoured locators or fitted templates
Occurrence -example
Modern ATM Machines – address this concern:
… chance that the complexity of process could lead to defects
Detection Poka-Yoke
In Detection, the situation
operator at the point of mistake
the
• For example, when one makes a mistake, an
effective Poka-Yoke system will alert the
operator that a mistake
• was made,
• where it was made,
• and even how the mistake was made
Detection -example
In Detection, these situation should alert the
operator at the point of mistake
• Four xample, when one makes a misteak, an
effective Poko-Yoke system will alert the
operotor that a misteak was made, where it was
made, and even how the misteak was made
Detection
Here are some techniques for detection oriented
Poka-Yoke:
• Use color coded parts/graphics or images
• Before the fact, or before the defective
part proceeds to the next step in the process, a
Poka-Yoke system should alert the operator that
100% quality does not exist
• It should be autonomous, or require almost zero
intervention, but be an automatic response to a
defect; almost reflexive
Detection -example
• IS GAS CAP SECURE?
– Tighten till you hear the “click”
Detection -example
• ARE YOU LOW ON GAS? (but… how low?)
- Detection
Detection -example
• LOW ON AIR? (but … which tire?)
- Detection
What are the Conditions?
(ripe for poka-yoke)
1.
Adjustments
8. Multiple handoffs
2. Unclear or no instructions 9. Hand processing
3. Undefined process
10. Rapid repetition
4. Many units/mixed units
11. High volume demand or
deadline pressures
5. Multiple steps
6. Infrequent production
7. Ineffective or lack of
standards
12. Environmental conditions
Go Forth
• Identify what your impediments to
improvement are and work on those.
• In particular - what are barriers to higher
equipment uptime, higher process
capability, safer equipment, higher capital
and labor productivity without adding cost
or more highly trained personnel, and you
will be on the right track.
• I call this building better process stability.
.
Better Practice Sharing
Surfin’ for Ideas?
A Better Practice …
In your Outlook Calendar
Use CAPS: (Action Verb) then, the
event …
A Better Practice …
Flow control
(3 lanes and 3 cash registers)
A Better Practice …
Label, Label, Label
Color code …
A Better Practice …
Which side is gas cap on?…
Points to left side
(see arrow)
A Better Practice …
Sign (Warning)
Metal tabs (Shut-out)
A Better Practice …
Visual Management…
Which one is the fork?
A Better Practice …
Countdown to Takeoff –
Get on the plane, people !!
A Better Practice …
Major Airline /Jet way Instruction
… bumper within 1”, but not touching
A Better Practice …
Green tag for “Carry On” bags that had to be checked.
A Better Practice …
Automatic flush, soap, and water . A locked trash
receptacle. Also, a touch-less motion sensor on paper
towels…
A Better Practice …
Slotted metal guard (“stand-off”) to prevent
accidently stopping luggage conveyor at the airport.
A Better Practice …
A Better Practice …
HEAT INDEX ALERT (signage) for outside operations.
Cool down stations / water identified (in blue) …
A Better Practice …
P.P.E. REQUIREMENTS to enter into the operation.
Steel toe shoes, reflective vest, hard hat, etc.
A Better Practice …
COFFEE/ SINK AREA (signage) for galley operations.
Considerate but firm…
A Better Practice …
TIME ALERT (signage) for coffee operations.
Denotes how long coffee has been sitting…
A Better Practice …
COFFEE STATION / ORGANIZATION
(standard layout) Visual indicator for supplies…
Summary
What Poka-Yoke IS NOT:
• Retraining people.
• Disciplining people who make mistakes.
• Work instructions.
• Improving the attentiveness of people.
• Increased human attention or intervention.
What Poka-Yoke IS:
• Poka-Yoke means “mistake proofing”.
• Poka-Yoke focuses on preventing and detecting
mistakes before they become errors…
• Poka-Yoke is classified as a control method but can be
considered as a solution to a problem as well if it
prevents it from occurring.
What Did We Cover Today?
In general, ‘Poka-Yoke’ (mistake-proofing) should
ultimately be
a foolish action:
 Common Guidelines for Poka-yoke
 (inexpensive, common sense, attack the root cause)
 BTW: Don’t do “Fake” Poka-Yoke
 Purpose of Poka-yoke (S,C,W)
 States – (Occurrence/ Detection)
 Operating ‘Conditions’ in which they breed …
 (multiple handoffs, undefined processes, adjustments, etc)
 Better Practice Sharing (they’re out there…)
- What is Your Poka-Yoke?
An idea you can put into practice…
www.freeleansite.com