md. imrul kaes root cause analysis 2013-4-17

7/28/2019 md. Imrul Kaes Root Cause Analysis 2013-4-17

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ROOTCAUSE

ANALYSIS

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If there is an unwanted recurring harmful situation

which consumes resources and tend to happen in

repeated fashion, then there is a possibility that it

might be beneficial to figure out what is really

causing the situation to occur and remove it so thesituation does not occur again. This is generally

referred to as root cause analysis, finding the real

cause of the problem and dealing with it rather than

simply continuing to deal with the symptoms.


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It raises several questions:

How does one determine which situations are

candidates for root cause analysis?

How does one figure out what the root cause is? Does the removal of cause entails less resource

expenditure than it takes to continue to deal with

symptom?


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DETERMININGCANDIDATES

In normal chaotic organizational environments, it is

often quite difficult to find candidates for root cause

analysis because the situations which repeat can

not attract the attention of almost anyone. When

organization really observes events carefully, it iseasy to determine which situations are recurring

with what frequency. Those situations which are

recurring with the greatest frequency and consume

the greatest amount of resource are the candidatesfor root cause analysis. Pareto analysis may

helpful in this case.


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GENERALPRINCIPLESOFROOTCAUSE

ANALYSIS

The primary aim of RCA is to identify the root causeof a problem in order to create effective correctiveactions that will prevent that problem from ever re-occurring.

To be effective, RCA must be performedsystematically as an investigation, with documentedevidence.

Root cause analysis can help to transform an oldculture that reacts to problems into a new culturethat solves problems before they escalate but moreimportantly; reduces the instances of problemsoccurring over time within the environment wherethe RCA process is operated.

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GENERALPROCESSFORPERFORMINGAND

DOCUMENTINGAN RCA-BASED CORRECTIVE

ACTION

Define the problem.

Gather data/evidence.

Identify the true root cause associated with the definedproblem.

Identify corrective action(s) that will prevent recurrence ofthe problem.

Effective solutions must be within your control, meet your

goals and objectives and do not cause other problems. Implement the recommendations.

Observe the recommended solutions to ensureeffectiveness.

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5 WHY

The Five Whys is a method for rapidlydetermining the root cause of a problempopularized by Taichi Ohno, the father ofthe Toyota Production System. His

technique was to approach any problem andkeep asking Whyuntil he was satisfied thatthe answer showed him what was really thesource of the problem. In doing so, he thenhad a good idea of what needed to be fixed

to prevent the problem. He called it the FiveWhys because he found over time that byasking why five times he usually ended upwith the right information to go and fix theproblem.

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Asking Why is a simple technique used to analyse

the causes of problems.

Asking Why simply involves repeatedly asking

why?' until the answer is becausethats the way it

is. At this point, it is likely that you have identified a

root cause of the problem. If tackled and removed,

the observed symptoms of the problem should also

disappear.

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First Why -Symptom

Second Why -Excuse

Third Why- Blame

Fourth Why- Cause Fifth Why -Root Cause


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ITWASNEEDEDTOMAINTAINTHECOLUMNOF

TRAFALGARNELSONTOWERIN LONDON.

1. Why it was needed for maintenance work of thattower? Because the stones were decaying because offrequent washing. The solution might be using lessharmful washing materials or less materials. But even

in that case washing could not be avoided.

2. Why were they being required washing? Becauseusually pigeons took rest there and made the placedirty by their waste.

In that case the solution might to set up such amachine which would make huge sound that wouldfrighten the pigeons. But the pigeons were the centerof attraction for the tourists. So it was not a goodsolution.


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3. Why were the pigeons come to that particularcolumn ? Because they used to come to eatspiders.

In this case the solution might be to spread insectskiller medicine on the column but it could harmhuman health. So it was not a good solution.

4. Why did the spiders use to come there? Becausethey used to come there to eat insects.

In that case we could use the solution of third whybut that was not a good solution considering humanhealth.


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5. Why did the insects use to come on that column? The insectsused to come on that column being attracted by the dazzling light of thatcolumn.

In that case the solution was to turn on the light of that column 30minutes later than the lights of the other columns so that the insects

would be attracted by the light of other columns.

30 minutes later lit the light of that column.

No insects on that column.

No spiders on that column.

No pigeons on that column.

No dirt.No detergent no washing.

No decay of expensive stones.

[No human health problem.

Tourists were similarly attracted to that square.]


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PROB 1: HIGHALTERRATEOFGARMENTS.

1. Why is there a high alter rate of garments?

Because there is high rate of oil spot.

2. Why is there high rate of oil spot? Because dust

gather inside the machines, absorb oil and release that

oil when the machines start run.3. Why does dust remains inside the machine for

long time? Because machines are not cleaned regularly.

4. Why machines are not cleaned regularly? Because

they only service machines when they break down orbecome problematic, not on a preventative basis.

5. Why only service after breakdowns? Because

maintenance says it is cheaper (but what about the cost

of rejects and rework?).


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PROB 2: HUGEAMOUNTOFRE-IRONING

1.Why is there a lot of re-ironing problem? Because afterironing and before packing, products have to be keptwaiting for long time often.

2.Why garments have to be kept waiting? Because ofshortage of finishing accessories.

3.Why there is shortage of accessories? Because freshmerchandisers regularly make mistake in giving timelyorder because of lacking of experience of handlingcritical orders.

4.Why fresh merchandisers handle critical order?

Because experienced merchandisers do not stay herelong.

5.Why experienced merchandisers do not stay here long?Because merchandiser manager behaves roughly withmerchandisers and gives poor direction.


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Although called Asking Why Five Times, five is a

rule of thumb. There may be more or less questions

depending on the particular situation.

Asking Why is a way of identifying the underlying

root cause of a problem so that this can be tackled

rather than dealing only with superficial symptoms.

It should be seen as a simple and quick alternative

to Cause and Effect Analysis.


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TORESOLVEORNOTTORESOLVE

Once the root cause is identified then it has to be

determined whether it costs more to remove the

root cause or simply continue to treat the

symptoms. This is often not an easy decision. Even

though it may be relatively easy to estimate the costto remove the root cause, it is generally very

difficult to assess the cost of treating the symptom.

This difficulty arises because the cost of the

symptom is generally wrapped up in some numberof customer satisfaction factors in addition to the

resource cost associated with just treating the

symptoms.


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FISHBONEDIAGRAM

Dr. Kaoru Ishikawa, a Japanese quality control

statistician, invented the fishbone diagram.

Therefore, it may be referred to as the Ishikawa

diagram. The fishbone diagram is an analysis

tool that provides a systematic way of lookingat an effect/problem and the causes that create

or contribute to that problem. Because of the

function of the fishbone diagram, it may be referred

to as a cause-effect diagram. The design of thediagram looks much like the skeleton of a fish.

Therefore, it is often referred to as the fishbone

diagram.


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WHENSHOULDAFISHBONEDIAGRAMBE

USED?

Need to study a problem/issue to determine the

root cause.

Need to identify areas for data collection.

Want to study why a process is not performingproperly or not producing the desired results.


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HOWISAFISHBONEDIAGRAMCONSTRUCTED?

List the problem/issue to be studied in the "head ofthe fish".

Label each "bone" of the "fish with majorcategories typically utilized which are:

The 4 Ms: Methods, Machines, Materials,

Manpower.

Identify the factors within each category that maybe affecting the problem/issue and/or effect being

studied.

Repeat this procedure with each factor under thecategory to produce sub-factors.


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CAUSE -EFFECTDIAGRAMTuesday,April16,2013

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Effect

Material

ManMachine

Method

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CAUSE -EFFECTANALYSISOFPOORPRODUCTIVITYTuesday,April16,2013

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Poor

productivity

Too much

waste of

energy

Poor

method of

working

Poor

maintenance

Poor

material

Poor staff

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CAUSE -EFFECTANALYSISOFPOORMATERIALSTuesday,April

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Poor material

goes to

customer

Improper work instruction

Poor

receiving

inspection

Poor Raw

material

No checking on production line

Poor QC

Lack of work

instruction

carelessness

Unstable

source; no

purchasing

policy

Bulk purchasing

Non conforming productfrom previous stage

Poor Final

product

Poor final

inspectionPoor QC

In process poor

material

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CAUSE -EFFECTANALYSISOFPOORSTAFFTuesday,April

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Poor staff

Accidents

Unstable labor

No team work

Extended shift work

Sickness

Lack of technical training

Low competence

Lack of skill training

Lack of motivation

Negative

minded

carelessness

Idleness

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PARETO ANALYSIS

Pareto analysis is a statistical technique in decision

making that is used for the selection of limited

number of tasks that produce significant overall

effect. It uses the Pareto Principal (also known as

80-20 rule) the idea that by doing 20% of thework you can generate 80% of benefit of doing the

whole job. Or in terms of quality improvement, a

large majority of the problems (80%) are produced

by few key causes (20%). This is known as the vitalfew and trivial many.

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HOWITISNAMED

In the late 1940s quality management guru Joseph

Juran suggested the principle and named it after

Italian economist Vilfredo Pareto, who observed

that 80% of income in Italy went to 20% of the

population. Pareto later carried out surveys on anumber of other countries and found to his surprise

that a similar distribution applied.

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The 80-20 rule can be applied to almost anything:

80% of the customers complaints arise from 20% of

your products or services.

80% of delays in schedule arise from 20% possible

cause of delays.

20% of your products or services amount for 80%

of your profit.

20% of your sales force produces 80% of yourcompany revenues.

20% of system defects cause 80% of its problem

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HOWTODRAWPARETOCHART

1. In a graph list the causes and their frequencies inpercentage form.

2. Arrange the causes in the decreasing order offrequencies that is, the most occurred cause will be onthe most left.

3. Add cumulative percentage column to the graph.4. Plot with causes on X-axis and cumulative percentage

on 2nd Y-axis.

5. Join the above points to form a curve.

6. plot a bar graph with causes on X-axis and cumulative

percentage on Y-axis.7. Draw a line 80% on Y-axis parallel X-axis. Then drop

the line with the point of intersection on X-axis. Thispoint on the X-axis separate causes on the left andless important causes on the right.

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DATA:

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Type of defect Frequency

1. Oil spot 50

2.Uncut thread 30

3.Dirty spot 3

4.Drop stitch 3

5.Cut stitch 3

6.Lebel mistake 3

7.Puckering 3

8. Hole 3

9. Shade 1

10. Uneven front back 1


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CHECKSHEET

Check sheet, also called defect concentration

diagram, is basically a data collection sheet. It is a

simple tool used to record data for further

processing. The data collection should be pre-

printed and highly systematic and structured, sothat recording the frequency of the problems

become easier.

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PROCEDUREFORPREPARINGCHECKSHEET:

Decide what event to be observed.

Decide when data will be collected and how long.

Design the form. Set it up so that data can be

recorded simply by making check marks or similar

symbols.

Label all spaces of the form.

Test the check sheet for a short trial period to be

sure it collects the appropriate data and easy to

use.

Each time problem occurs, record data on the

check sheet in tally format.

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ANEXAMPLEOFCHECKSHEETFORDATA

COLLECTIONTuesday,April

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Check Sheet

Dept. Name Order no. Style no.

Line. No. Inspector name. Date:

Type of defect Checks Frequency (%)

1. Oil spot lllll lllll lllll lllll lllll lllll lllll lllll lllll

lllll

50

2.Uncut thread lllll lllll lllll lllll lllll lllll 30

3.Dirty spot lll 3

4.Drop stitch lll 3

5.Cut stitch lll 3

6.Lebel mistake lll 3

7.Puckering lll 3

8. Hole lll 3

9. Shade l 1

10. Uneven front back l 1

Total 100 100%


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Success from a data collection sheet largely

depends on classification of problem types. A

wrongly designed and inappropriately classified

data sheet may not carry any significant information

for further analysis.

Data can be collected randomly, on different days,

at different times, in different line, for different

styles, for different buyers in order to clearly pointout reasons for defects.

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md. imrul kaes root cause analysis 2013-4-17

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