8D - The 8
Disciplines Process
The
8 Disciplines (8D) process
is a problem management tool popularly used in responding to customer
returns or issues. Its effectiveness stems from the fact that it
incorporates all the important aspects of problem management, i.e.,
containment of the problem, root cause analysis, problem correction, and
problem prevention.
The output of an 8D process is the 8D report, the format of which
follows the steps of the 8D process. Below is the basic outline of an 8D
process/8D report.
Discipline 1. Form the
Team
This is the first
step of the 8D process and the first part
of the 8D report. This step defines the composition of the
8D team. The
team should be cross-functional and should include as members the
process owner, a member from QA, and others who will be involved
in the containment, analysis, correction and prevention of the
problem. The names of the members as well as their positions in
the company organization must be enumerated in this part of the
report.
Discipline 2.
Describe
the Problem
This
step involves a detailed assessment of the problem highlighted by
the customer. Under this step, the 8D report provides
background information on and a clear picture of the problem being
highlighted by the customer. It should include the following
details: a) the identity of the customer; b) a description of the
customer application; c) device information (device, package, lot
#, date code, etc.; d) when the problem was encountered; e) where
the problem was encountered; f) a specific description of the
failure mode; and g) failure rate.
Discipline 3. Contain
the Problem
This
discipline explains the extent of the problem and bounds it.
Based on initial problem investigation, all lots that are
potentially affected by the same problem must be identified and
their locations pinpointed. If possible, specific lot #'s
and/or date codes of potentially affected lots shall be enumerated
in this portion of the report.
Lots
that are still in the factory must be put on hold until their
reliability has been properly assessed. They must only be
released if the lots are either proven to be clean or the failures
may be effectively screened.
If the
problem has an extremely high reliability risk and the application
of the product is critical (e.g., failure of the product is
life-threatening), lots already in the field may need to be
recalled. However, recall must only be done under extreme
cases wherein the impact of reliability risk is greater than the
impact of recall.
Discipline 4. Identify
the Root Cause
This 8D
process step consists of performing the failure analysis and
investigation needed to determine the root cause of the problem.
The corresponding portion in the 8D report documents the details
of the root cause analysis conducted. A detailed description of
the actual failure mechanism must be given, to show that the
failure has been fully understood.
The
root cause is then presented, showing how it triggered the failure
mechanism identified. All events emanating from the root cause and
leading to the failure mechanism must be included in the
explanation. As much evidence as possible must be provided to show
that the root cause is the real culprit behind the problem. The root cause must also be
correctively actionable.
Discipline 5.
Formulate and Verify Corrective Actions
This next discipline
identifies all possible corrective actions to address the root
cause of the problem. The owners of the corrective actions and the
target dates of completion shall be enumerated in this section of
the report. It is also suggested that the rationale behind
each corrective action be explained in relation to the root cause.
Sometimes, identification of the best corrective action(s) for the
root cause requires preliminary evaluations and studies before
they can be implemented. This is referred to as
'verification of the corrective actions.' This must be done
especially in cases wherein the affected volume is very large,
since an incorrect solution deployed over a large inventory will
result in wastage of crucial time and money.
Discipline 6. Correct
the Problem and Confirm the Effects
The sixth
discipline of the 8D process involves the actual implementation of the identified corrective
actions, details of which must be documented in the corresponding
portion of the 8D report. The dates of completion and owners of the corrective
actions must be shown in this section. Data showing that the
corrective actions are effective in preventing the root cause of
the problem must be presented. Any deficiency in the effectiveness of the
corrective actions must be addressed by improvements in or
additions of corrective actions.
Discipline 7. Prevent
the Problem
This
next discipline should not be confused with 'correcting' the
problem. Prevention of the problem entails the
identification of devices or packages that are similarly
vulnerable to the same problem highlighted by the customer, even
if not affected under the current situation. Actions
necessary to prevent these from being affected by a similar
problem in the future are called preventive actions. All
preventive actions must be enumerated, along with their owners and
target dates of completion.
An
important aspect of this discipline is the standardization and
deployment of corrective actions or process improvements to all
products that may possibly be subjected to the same issue.
Discipline 8.
Congratulate the Team
The last
step of the 8D process and the last portion of
the 8D report consists of an acknowledgement from management of the good work
done by 8D team. Approvals for the 8D report are also shown
in this last discipline.
See Also:
TPM; TQM; Kaizen; 6-Sigma; Poka-Yoke