Six Sigma Tool Navigator: The Master Guide for Teams

2017-07-07 02:10:07

AKA

N/A

Classification

Changing/Implementing (CI)

Tool description

The potential problem analysis (PPA) is a tool used for minimizng the probability of solution implementation failure by identifying potential problems and possible countermeasures.

Typical application

To anticipate and analyze potential problems.

To identify potential problems that could cause delays, difficulties, or outright failure in the implementation of a solution.

To estimate the risk of project failure and the cost of prevention.

Problem-solving phase

→	Select and define problem or opportunity
→	Identify and analyze causes or potential change
→	Develop and plan possible solutions or change
	Implement and evaluate solution or change
	Measure and report solution or change results
	Recognize and reward team efforts

Typically used by

	Research/statistics
4	Creativity/innovation
2	Engineering
	Project management
3	Manufacturing
	Marketing/sales
	Administration/documentation
	Servicing/support
	Customer/quality metrics
1	Change management

links to other tools

before

Problem Analysis

Activity analysis

Barriers-and-Aids Analysis

Reverse Brainstorming

Action and Effect Diagram (AED)

after

Action Plan

Resource Requirements Matrix

Consensus Decision Making

Countermeasures Matrix

Facility Layout Diagram

Notes and key points

The team may identify potential problems as seen from this example.

What? Parts not available when needed

Where? At "parts assembly" workstations

When? First 10 days of each month

Who? Required by operators of all shifts

Extend? Could shut down the assembly process

Suggested definitions and scales.

R -		Risk in implementation (1–10): The amount of risk a potential problem may bring to the implementation of solution. A rating of 1 stands for very little risk, a rating of 10 may prevent implemetation altogether.
P -		Probability of occurrence (1–10): An estimate of probability for a potential problem to materialize. A rating of 1 is very low, 10 is extremely high.
RP -		Residual probability (1–10): A reestimated probability for a potential problem to occur after appropriate counter measures may prevent a potential problem from appearing. A rating of 1 is very low, 10 is extremely high.
C -		The estimated cost of counter measures or contingency plans. L = low cost, M = medium cost, H = high cost.

Step-by-step procedure

STEP 1 First, a facilitated team determines a set of solution implementation goals and all activities required to successfully reach these goals.

STEP 2 Using the reverse brainstorming method, a list of potential problems is developed and recorded on a whiteboard.

STEP 3 The list of potential problems is used to draw a table of potential problem analysis. See example Implementation of a Just-in-Time (JIT) Manufacturing System.

STEP 4 The facilitator asks participants to analyze each potential problem by asking: what? where? when? who? and to what extent? This will provide more detailed information for risk estimation.

STEP 5 Next, the team discusses the amount of risk each potential problem brings to the implementation effort. After reaching consensus on the risk estimates, the probability of problem occurrence is estimated. Ratings are placed with the potential problems in the table, as shown in this example.

STEP 6 Team discussion follows on the possible prevention of potential problems. Countermeasures are identified and the residual probability of occurrence estimated. The residual probability is estimated on the basis of a greatly reduced probability of problem occurrence after countermeasures have been placed into effect.

STEP 7 Lastly, contingency plans are agreed upon just in case the countermeasures will not significantly affect the most serious problems.

STEP 8 To complete the potential problem analysis table, costs are estimated for countermeasures and contingency plans.

STEP 9 The team reviews the table, makes final revisions, dates the table, and presents this analysis to the process owners.

Example of tool application

Implementation of a Just-in-Time (JIT) Manufacturing System Date:xx/xx/xx

ID	Possible Causes of Potential Problems	R	P	Countermeasures to Prevent Problems	RP	C	Contingency Plans for High-Risk Problems	C
A	Suppliers cannot meet delivery schedule	8	5	Select and certify more suppliers	2	M	Acquire (purchase) supplier company	H
B	Parts not available when needed	10	7	Rearrange work, balance supply	4	M	Stock critical parts	M
C	Managers show resistance to change	5	4	Get managers involved early	2	L	Rotate, transfer decision-making	L
D	No direct operator involvement	5	9	Establish self-directed work teams	4	M	— — —
E	Bottlenecks exist; no workflow balance	6	7	Perform process and cycle time analyses	3	H	— — —
F	Lack of operator JIT training	4	8	Schedule operator JIT training	0	M	Engage outside training firm	M
G	No self-inspection methods in place	3	8	Develop practices and procedures	0	L	— — —
Notes: R = Risk, P = Probablility, RP = Residual Probablity Scale 1–10, 1 = LowC = Cost; L = Low, M = Medium, H = High