Mistake-Proofing
Everyday
Activities
Can You Mistake-Proof Your Wife?
Life?
by
Dr. Neal Jeffries
Osher Lifetime Learning Institute
Reminders for your Automatic Memory
such as where you put your keys, glasses, wallet or purse,
watch, phone, etc..
These Reminders are called “Poka-Yokes”
or “Mistake-Proofing Devices”
Example: I had dinner out with a friend and she took home about
half of her dinner in a carry-out box. Then we stopped by my
condo to watch a show I had recorded on my DVR. While she
was there, I went to the fridge and discovered the carry-out box,
along with her keys on top of it, right there in the fridge.
What was her purpose?
Is there any way to improve on this Poka-Yoke?
My Short-Term and Long-Term Memories are not
too bad, but my Automatic Memory is constantly
giving problems, such as “Where are those keys”.(or
Hammer & Nails)
But fortunately, these problems can be managed
by extensive use of Poka-Yokes or Reminders, such
as Check Lists, Visible Reminders, and especially
Preventative Reminders.
Here’s a Preventative Poka-Yoke if you leave
items on top of your car :
Book
Car Keys
Do you sometimes make simple, irritating
little mistakes such as:
Misplacing keys, glasses, wallet, purse,
etc.?
Forgetting to take the important mail with
you when you went to the P.O.?
Leaving credit card, license, other
important items, where they should not be?
Forgetting why you went into the bedroom,
bathroom, or workshop, etc.?
Setting something down for just a moment
and then not being able to find it?
Putting something important in a special
place just so you won’t forget it, and then
forgetting where was the special place?
IF SO, THIS CLASS MAY HELP YOU!
Examples: Recent Lunch
Credit Card
– Leave wallet out
Wallet
– On top of keys
Sunglasses
– in pocket, attached to hat, extras
Gloves
– in coat pocket
Jacket – Sleeve tucked into pocket
Hat – in coat pocket or on top of keys
or have extras
Some other methods that have worked:
Post it notes on something I always take with me such
as wallet, pocket calendar, keys, folder for
meeting, etc.
Put change for parking meter in glove to transfer to cup
holder in car
My parents had their own methods to reduce mistakes:
When Mom called me, it was usually,
“DonRexNeal…”
which became, for all of us, just, “Boy”
My Dad called all of his granddaughters, “Suzie”
My Journey with Poka-Yoke
I used the Zero Defects Program, devised by the
Air Force, at General Electric. It did not work.
Then in 1985 I heard about the Mistake-Proofing
System invented by a Japanese engineer, Shigeo
Shingo, and called Poka-Yoke. It accepted the fact
that people do make mistakes, but it is possible to
keep them from going out the door.
Similarly, you and I make many mistakes such
as forgetting things, but if we have systems to remind
us, we can avoid many problems
So I studied Mistake-Proofing and started
teaching classes for the Society of Manufacturing
Engineers, and later for Saddle Island Institute and
then for National Business Institute. Shigeo Shingo,
who wrote the first book on it, personally taught me
some things about it also when he visited Cincinnati,
and also when I took a group to Japan.
So I had a chance to see it in action in Japan,
and then later in many plants in the U.S.
Mistake-Proofing Example
At a television assembly plant, workers applied
strips of insulating tape to ten connections on the
chassis. The strips were attached to a rod just
over the chassis.
Occasionally, a worker would make a mistake
and miss applying the tape to one of the
connections. This caused rejects and rework.
How could this problem be eliminated?
Insulating Tape
Rod
The solution chosen was to arrange the
insulating strips in groups of ten, so that
the worker would be sure to complete
the entire group of insulating strips
before moving on to the next chassis.
OTHER SOLUTIONS?
Colors : Different color or different fabric at end of group.
Last one in group rings a bell, etc.
What is the best solution?
Three Methods for Mistake-Proofing
1. Warning Method: lights, bells, colors,
appearance of something unexpected
or disappearance of something
expected to be there, anything that
gets your attention.
2. Control Method: the system corrects
mistakes automatically such as drain
holes to prevent overflowing, pen with
retracting point, etc.
3. Prevention Method: electrical cord with
plug that cannot be inserted
incorrectly, camera cord with notch in
corner, diesel gas nozzles, etc.
Which System was used for the
insulating tapes?
Example of Different Methods for Mistake-Proofing
Problem: Have to remember to take a book to the
library, when I go out in the car. (I sometimes
forget)
No Method:
Leave book where it is and try to
remember to take it.
Warning Method:
Put book on table near door or hang
it in a bag on the door handle.
Control Method:
Put book in front of door, so you
can’t open the door without moving it.
Prevention Method:
Put book in car right now.
-
-
“Absolutely certain” method: In front of door.
Except with granddaughter and swimsuit; she just brushes it aside
with her foot and goes on out the door.
This gas-cap design has
three Mistake-Proofing
ideas included:
1.The tether keeps the cap
from getting misplaced.
2.The gas tank inlet is sized
so that only the correct fuel
nozzles can enter it. For
example, diesel fuel nozzles
are too large to fit in.
3.The gas cap has a ratchet
such that the cap cannot be
over-tightened.
Many gasoline hoses are designed with a break-away feature,
so that if you forget and drive off before disconnecting, it
won’t cause a major spill and possible fire.
Philosophy of this Seminar:
“A Mistake is an Opportunity for Improvement”
When a Mistake is made, do you…
➢Ignore it?
➢Hide it? (Comment by attendee in coffee shop)
➢Hope it isn’t noticed or goes away?
➢Decide that you are going to concentrate more?
➢(Similar to the Seminar Speaker trying to be heard)
➢Complain about it?
➢Blame it on someone else?
➢Try to change things
➢ so that it doesn’t happen again?
Count the E’s and e’s in this passage
Shockwatch – a series of products which measure shock. These are
intended to reduce damage to equipment, packages, vehicles, etc., by
monitoring the shocks that the item receives.
For example, when mounted on a forklift truck the device can be made
to stop the vehicle when a certain level shock is received, such that it
cannot be started again without a special key available from a certain
supervisor.
In one company where this is used on all forklifts, because anyone is
allowed to use them, it has resulted in about 50% decrease in accidents.
This is because people are more careful about driving them, and also
because the system requires the operator to sign in before using a truck.
Thus, if there is a collision, not only is the current operator identified, but
also the drivers have become more careful so that the truck will not be
disabled while they are driving.
Another form of the product is labels on shipped packages which
indicate if the package receives unusually rough handling. The label
changes appearance if the package experiences shock of a particular
magnitude.
Results: After about 10 years of experience with people
counting the e’s in a passage like this, the results for about
1000 participants were that less than 2% were able to count
the correct amount.
In other words, counting errors are almost
everywhere!
Usually
CALENDAR Misplaced
Items:
Phone
Keys
Wallet or Purse
Watch
Purse
or
Wallet
Cell Phone
Keys Watch
Pocket Calendar
This sensor at the door picks up a signal if something leaving
the store has not been checked out correctly.
Some smoke detectors have ways of indicating if there is no or a
low battery, by not snapping together or emitting a beep.
This cash-o-matic machine counts and dispenses the correct change
every time. Some of them have a signal if the change is not
collected?
This french fry scoop has been in use for many years, and it continues to
give about the same number of french fries each time.
If Ketchup is stored upside-down, then the water comes to the top.
So when you squeeze the bottle to get some ketchup, you get the
viscous fluid you want instead of the water. These bottles are
designed to be stored upside-down.
These school buses are equipped with a wire strucure around the front bumper.
This causes the children to pass in front of the bus at a distance where the bus
driver can see them at all times.
Mistake-Proofing With Post-It Notes
I have used this when
Doctor’s
watching TV, and thinking Appointment
of something I’m supposed At 4 pm
to do the next day
SERVICE CHECKLIST
Change Oil Changed
Change Oil Filter OK
Check Air Filter OK
Check Wiper Blades Completed
Vacuum Floors Completed
Wash Exterior Windows
Additional Services as Needed:
Lubricate Chassis Sealed
Check Trans. Fluid OK
Check Diff. Fluid N/A
Check Pwr. Ster. Fluid OK
Check Wind. Wash Fluid Added
Check Battery Fluid OK
Inflate Tires to Prop. Pres F32 R32
Breather Element N/A
PCV Valve N/A
Check Brake Fluid OK
Window Sticker Completed
Lights OK
Checklist for Mistake-Proofing
Another Template
5-26
Supermarket Shopping
- List, by Aisle
Aisles 2-3
Butter
Cheese
Eggs
Milk
Etc.
Would this help you to remember to ask for your Senior Discount?
Examples Of Mistake-Proofing Systems
1. Calendars & Schedules.
2. Check Lists. including just lists, double and cross
3. Color-Coding to emphasize, differentiate, etc.
4. Reminder Signs: No Smoking, Take Laptops Out of
Luggage, Rest Rooms, Names of Businesses.
5. Tie things together, such as a letter in the wallet or
purse.
6. Visuals such as clothes, tools, food, etc. hanging
in view
7. Clock, Alarms, Dates on Newspapers, etc.
8. Instructions on how-to, such as Recipes
9. Information on Food Packages: Ingredients, How
to Prepare, Nutrition Information, Warnings about
peanuts, etc.
10. Motivators such as slogans, songs, sayings,
pictures, rewards, attaboys, etc.
11. All the many kinds of traffic signs: Stop, Speed
Limit, Parking Hours, One-Way, Street Names.
SUMMARY OF MISTAKE-PROOFING
1. It is possible to Mistake-Proof many
aspects of your life.
2. It mainly requires the philosophy of trying
to devise systems that work for you, be
they warning, control or prevention.
3. If at first you don’t succeed, try again.
Then give up for awhile, or ask someone
else for their ideas.
4. It’s kind of fun to try it, and when
something works it makes your life more
enjoyable and less frustrating.
The
End
Using a staging or template method,
mistakes were virtually eliminated.
COUNTING PROBLEMS
Occurrences: Assembly, Order-Picking, Shipping,
Inventory, Financial Reports, etc.
SOLUTIONS:
1. Multiple Counts
2. Computer Counter
3. Automatic Counter
such as on a machine, electrical,
mechanical, digital, bar code, vision, etc.
4. Weighing or Measuring for standard Parts
5. Templates
-
M-P Examples
from the Internet
from John Grout’s site
(go to M-P Examples 1-10, under All Files)
Fast food restaurants have been using visual cash registers like these
for years, so that the employee is more likely to ring up the correct sale.
Notice the color-coding for types of products. Some software even has
pictures of the products.
Some drills have a sensor such that, if you hit a wire or cable,
they will stop automatically
With this ATM, you don’t
have to insert your card.
You merely swipe it
through a slot and the
transaction can
proceed. No more
forgotten or impounded
cards.
Most, but not all, elevators have sensors to prevent the doors
from closing when someone is in the way. Also, they often
are prevented from operating if the maximum weight is
exceeded.
To keep pipes from freezing during a cold
winter, some people let a little water keep
running when they are gone. This pipe
does the same thing automatically.
These shower heads are equipped
with an anti-scald sensor, which
turns off the flow if the water is too
hot.
Some wallets are now
equipped with a bell that
rings if a credit card is
removed and not
returned before the
wallet is closed.
Synopsis: Improving Your Memory
1. Recall from Long-Term Memory:
Prompts -“FLIP PART”
2. Short-Term Memory Retention and Recall:
Pegs (One=Gun, Two=Shoe, etc.)
3. “Automatic Memory” Lapses:
Poka-Yokes (Letter in front of door)
4. Names & Faces: Repetition, Pictures
5. Mnemonic Devices: Poems, Sayings, etc.
(Spring ahead; fall back)
6. General Helpers:
Diet:“What’s good for the heart is good for the brain
Supplements: Antioxidants - Vitamins C and E; B12
Physical Exercise: Regular, Not too strenuous, such as 3X
weekly walk of 45 min.
Mental Exercise: Puzzles, Memorizations, Math & Logic
Problems, Scheduling, Cooking, Bridge
Meditation: Breathe in for 7 sec, out for 7 sec, Rep 7X
Prayer, if it works for you.
7. Chunking and Linking:
Chunk couples you wish to remember, link friends
or those with similar interests
Templates for Mistake-Proofing
-
Pictures for Mistake-Proofing
Colors for Mistake-Proofing
-
Color-Coding helps ensure
that similar items are not mixed up
I taught Classes in Poka-Yoke for about
20 years. They were very popular and useful
for most companies, in my experience.
I learned to use the mistake-proofing
methods in my own work, and then in my
personal life.
I have found that it does not eliminate all
mistakes, but it does prevent most of them.
It shows me that perhaps all mistakes
can be eliminated or reduced, if I take the time
to implement the system completely.
Excerpt from Zero Quality Control by Shigeo Shingo
“In 1977 I hurried to Shizuoka Plant of Matshushita
Electric’s Washing Machine Division when I heard that
the facility had achieved a continuous record of one
month with zero defects in a drainpipe assembly line
operation involving 23 workers.
When I got there, I found that this significant goal had
been attained by the use of source inspections, self-
checks and by the installation of effective poka-yoke
devices – ingenious and relatively inexpensive
mechanisms that everyone had cooperated in
coming up with.
Before the Matsushita's accomplishment, I had
secretly been afraid that it might be impossible
for a drainpipe assembly line employing so many
workers and handling 30,000 units each month to
actually go through an entire month with zero
defects.
Seeing this achievement gave me an
unprecedented jolt, therefore, and I drew
boundless confidence and courage from the
realization that given the proper conceptual
approach and appropriate techniques, and given
suitable leadership and general enthusiasm and
cooperation, people can in fact achieve things
that have been thought to be impossible.
The Matsushita Washing Division's Shizuoka
plant continued zero defect production for
over six months, and I confidently appealed to
a number of other plants with the assertion that
they, too, could achieve zero defects for the
space of one month.
Lo and behold, these plants began to
achieve zero defects for one month, and even
for several months running.“
So, Poka-Yokes
DO WORK!!
Possible Opportunities for Mistake-Proofing
(for trying to solve today)
1. Forgetting Names, Dates and Places.
2. Forgetting Passwords or Numbers (Pin, etc)
3. Misplacing Keys, Glasses, Wallet or Purse, Watch,
etc. Leaving items on top of car.
4. Taking Medications at the right time
5. Leaving Gloves on tables; leaving Napkin tucked
into belt, failing to Zip up pants
6. Misplacing Multiple Items, such as tools or gift-
wrapping items.
7. Leaving Children or Pets in wrong place.
8. Others?
SOME KINDS OF TEMPLATES
SPACES: 1 2 3 4 5 6
HOOKS OR PEGS:
SLOTS:
RACKS:
BOXES:
BOWLS:
SHADOW BOX
OR INDENTATIONS:
