QS-9000 is the name for the Quality System Requirements used to increase customer confidence in the quality of its suppliers.

The idea of QS-9000 is quite similar to ISO-9000, International Quality System Standard, but QS-9000 applies particularly to the automotive industry for Chrysler Corporation, Ford Motor Company, General Motors Corporation, and truck manufacturers. QS-9000 is made up of three sections: an ISO-9000 based requirement, a sector-specific requirement, and a customer-specific requirement. These requirements guarantee a supplier procures a good quality product. Furthermore, by developing QS-9000, we will be able to improve our product, customer satisfaction, and supplier relations as well.

                          Standards for ISO-9001 and QS-9000
                                                                   ISO   QS
          Quality System Requirements                             9001  9000    
          Management Responsibility                                 X     X
          Quality System                                            X     X
          Contract Review                                           X     X
          Design Control                                            X     X
          Document and Data Control                                 X     X
          Purchasing                                                X     X
          Control of Customer-Supplied Product                      X     X
          Product Identification and Tractability                   X     X
          Process Control                                           X     X
          Inspection and Testing                                    X     X
          Control of Inspection, Measuring, and Test Equipment      X     X
          Inspection and Test Status                                X     X
          Control of Non-Conforming Product                         X     X
          Corrective and Preventive Action                          X     X
          Handling, Storage, Packaging, Preservation and Delivery   X     X
          Control of Quality Audits                                 X     X
          Training                                                  X     X
          Servicing                                                 X     X
          Statistical Techniques                                    X     X
          Production Parts Approval Process                               X
          Continuous Improvement                                          X
          Manufacturing Capability                                        X
          Customer-Specific Requirement                                   X

Back to Original Page


Quality means a totality of characteristics of an entity that bear on its ability to satisfy stated and implied needs. In some references, Quality is referred to as "fitness for use", "fitness for purpose", "customer satisfaction", or "conformance to the requirements."

To achieve satisfactory quality we must concern all stages of the product or service cycle. In the first stage quality is due to a definition of needs. In the second stage it is due to product design and conformance. In the last stage quality is due to product support throughout its lifetime.

There are two major aspects of quality: quality of design and quality of conformance. Quality of design involves the variations of a product or services in grades or levels of quality. This includes the types of materials used in construction, tolerance in manufacturing, reliability, etc. Quality of conformance concerns how well the product conforms to the specifications and tolerances required by the design. Quality of conformance is influenced by the choices of manufacturing processes, training and supervision of the workforce, the type of quality-assurance system used, and the motivation of the workforce to achieve quality.

Back to Original Page

Quality at Source (Source Inspection)

Source inspection is a technique used to prevent product defects by controlling the conditions that influence quality at their source. It is the performance of the supplier's facilities to increase customer confidence with the supplier's product quality. The following elements are essential parts of source inspection.

It is important to have either external or internal company inspectors to assure adequate product control. A sources inspection is performed to insure that the decision making is correct and unbiased. Furthermore, source inspection can be devised into two categories as follows;

  1. Vertical source inspection inspects the process flow to identify and control external conditions that affect quality.
  2. Horizontal source inspection inspects an operation to identify and control interval conditions that affect quality.

Back to Original Page

SOP - Standard Operating Procedures

Standard Operating Procedures (SOP) are the instructions that cover operational parts. Initially, an SOP is based on Armywide publications and then modified to use local operating conditions and command policies as a guideline. The scope of SOP is extensive and varies. It provides the major instructions for all division elements of operational features.

In general, there are two formats for an SOP to follow:

Back to Original Page

SMED - Single Minute Exchange of Die

SMED, often called "Quick Changeover", is an process that can help us to reduce downtime due to set-ups and changeovers. Quick Changeover means we reduce time to set up a machine or process. We use SMED as a guideline to eliminate our waste changeover time in our production process, especially while changing a machine from one product to another.

There are six major steps that we should be concerned with :

  1. Ensure that everything needed for setup is already organized and on hand to save time finding something in the process setup.
  2. It is good to move your arms but not your legs to avoid spending too much time during adjustment or set-ups.
  3. Do not remove bolts completely to save time during removing bolts and setting up the process.
  4. Regard bolts as enemies; do what ever you can to get rid of them to save time by using some equipment that is better than bolts when changing the process.
  5. Do not allow any deviation from die and jig standards to save time by using the same standards. For example, use the same size of nut and bolts for each die and jig.
  6. Adjustment is waste to make the jig or figure simple to setup and avoid wasting time to adjust the positions.

Back to Original Page

SPC - Statistical Process Control

Statistical Process Control (SPC) is an collection of statistical techniques that are used to monitor critical parameters and reduce variations. We used SPC to achieve process stability and improve the capability through reduction of variability. Often the term "Statistical Quality Control" is used interchangeably with "Statistical Process Control."

The objective of SPC is to get a process under control. This is done by identifying and eliminating any specific causes of variation not associated with the process itself. A process that is in control will constantly perform within its own natural limits.

SPC can be broken into two components: process control and acceptance sampling. In process control, SPC involves these seven tools: Histogram, Check Sheet, Parato Chart, Cause and Effect Diagram, Defect Concentration Diagram, Scatter Diagram, and Control Chart These tools often called "The Seven QC tools." Most of the tools help us to identify a problem in the process. Acceptance sampling is used to reduce variation in the process by using statistical sampling techniques to select the proper sampling size and to interpret whether our whole product should be accepted or rejected.

Back to Original Page


Sampling is the process of obtaining samples from a large group of data (or called population). There are numerous data, so it is difficult or impossible to examine the whole group. Examining all data will expend a lot of time, so doing only a small part of entire data, a sample, is more appropriate. Additionally, sampling theory is a study of the relationship between the whole data and the samples. It is useful to understand whether there are differences between two samples.

All possible samples of size n can be drawn from a given population. For each sample, we can calculate a statistic; for example, the mean and the standard deviation of the data will vary from sample to sample. So a sampling distribution is useful to explain the data characteristics.

There are three types of sampling processes:

  1. Single sampling is composed of selecting a specifically random sample of n items from each group of items presented, and then condemning each group depends up on the results. For example, chose n items from each group for inspection. We will accept the group if the number of defects is less than or equal to d, a specific value. Otherwise, we will reject them.
  2. Double sampling is composed of selecting two specifically random samples of n1 and n2 from data. By a technique of this type, the results of selecting a first sample (n1) are accepting the group, rejecting, or talking another sample of n2 items. The decision making depends on the associated results.
  3. Multiple sampling is a technique of sampling that is similar to the double sampling, but there are more than two sampling items used in decision making.

Back to Original Page

Scatter Diagram

A scatter diagram is a graphical diagram to show the relationship between two data variables. It is used to display the change of one variable when another changes. From a scatter diagram, we can find a mathematical equation that relates to the variables. To create a scatter diagram, these steps are followed:

From a scatter diagram, curves are tentatively devised for linear and non-linear curves. With this, we can call two relationships between variables to linear and non-linear relationships.

Back to Original Page

Self Inspection

Self inspection is a technique of inspection in which workers check their own work. Self inspection provides the most immediate feedback. With this technique, the worker may accept products that ought to be rejected. Furthermore, the worker may not notice all the errors.

On the other hand, if the errors in decision and careless mistakes are eliminated, self inspection would be the efficient technique. However, it could be improved by developing tools or using devices that could automatically detect defects or mistakes. Providing new knowledge of quality processes to workers is an efficient method to improve the self inspection technique.

Generally, the results from inspections are reported in terms of the total percentage of defects. With this method, inspectors will check the final products. They may find some mistakes or product errors, but they will not know the actual error source. As mentioned, self inspection is a method to solve this problem.

Back to Original Page

Sensory Inspection

Inspections involve distinguishing acceptable from unacceptable goods and comparing them with a standard. Sensory inspection is a kind of inspection, conducted by the human senses, such as inspections of paint saturation or judgments of plating adequacy. They are different from physical inspection, which involves the use of devices, like calipers, micrometers or gauges, to measure.

For inspection of this kind, it is difficult to set criteria because it depends on the physical condition of human workers, the period of work, and the skills acquired from experience. Naturally, different people have different senses and even the same person may make different judgments at different times. It is laborious to judge an object with a complex form or a not-well-defined shape.

Back to Original Page

Seven Steps or Seven QC Steps

The 7 QC Steps process is a structured problem solving approach for improving weak processes. This approach is known as reactive improvement. The 7 QC Steps is easy to understand and learn, easy to use, and easy to monitor.

The 7 QC steps process is structured as follows:

Step 1: Select a Theme. In this step, the weakness in the process or the problem to be solved is clarified in a theme statement. A Flowchart, a Theme Selection Matrix, or a Cause & Effect Diagram is used as a tool in this step.

Step 2: Collect and Analyze Data. This step focuses facts about the problem and discovers what types of problems occur frequently. When collecting data, you must think of all possible causes. Checksheets and Pareto Diagrams are the tools most often used.

Step 3: Analyze Causes.With sufficient data from step 2, the root cause, or fundamental cause, is found by constructing a Cause & Effect Diagram.

Step 4: Plan and Implement Solution. In this step, you brainstorm for ideas that are causing the problem and develop a solution that prevents the root cause from recurring. Then, you implement an adjustment to the process. The 4W's and 1H Matrix (What, When, Where, Who, and How Matrix) is used to develop a plan.

Step 5: Evaluate Effects.You evaluate the effects of implemented solution to make sure the solution worked and does not have unacceptable results from the comparison of data, before and after the implementation of the solution. In this step, comparative Pareto Charts and Graphs are frequently used to identify the results.

Step 6: Standardize Solution. A standardized solution is confirms that the old process is replaced with an improved process and indicates that the solution is workable. A flowchart is most often used.

Step 7: Reflect on Process and the Next Problem. In this step, you consider what the team's accomplishment was in the first 6 steps and recommend a weakness to work on next.

Back to Original Page

7QC Tools

Seven QC tools are fundamental instruments to improve the quality of the product. They are used to analyze the production process, identify the major problems, control fluctuations of product quality, and provide solutions to avoid future defects. Statistical literacy is necessary to effectively use the seven QC tools. These tools use statistical techniques and knowledge to accumulate data and analyze them.

Seven QC tools are utilized to organize the collected data in a way that is easy to understand and analyze. Moreover, from using the seven QC tools, any specific problems in a process are identified.

7QC tools always include :

Back to Original Page