Guide to Quality Optimization: SPC, Six Sigma, TPC, Lean Manufacturing

Other than the features and price, quality takes an important role to provide a product’s value. One way to make sure a product’s quality is maintained is by implementing a strong and adaptable Quality control (QC) strategy.




Quality control (QC) is a critical process that helps organizations ensure that their products or services consistently meet the required quality standards. QC processes are essential in maintaining customer satisfaction, reducing waste, optimizing resources, and improving productivity and profitability. To achieve all this, a comprehensive QC protocol should first be determined by businesses.

The four most popular methodologies of the standard QC protocols include:

  1. Statistical Process Control (SPC)
  2. Six Sigma
  3. Total Process Control (TPC)
  4. Lean Manufacturing




1. Statistical Process Control (SPC) 

Statistical process control (SPC) is a QC approach done by monitoring and managing processes that makes use of statistical tools. SPC aims to make a process predictable and stable while ensuring that its output remains constant over time. In order to decide whether the process is within the control limits, SPC entails measuring and analyzing the process data. Corrective action is conducted to regain control of the process if it gets out of hand.

SPC is a useful tool that businesses can adopt to monitor and manage their processes. It enables businesses to spot process differences and make necessary adjustments before the quality of their output is impacted.


2. Six Sigma
Six Sigma is a data-driven methodology used to enhance processes and lower faults. It aims to generate a process with no more than 3.4 errors for every million chances. Six Sigma involves five phases: Define, Measure, Analyze, Improve, and Control (DMAIC).

The DMAIC method assists businesses in identifying the source of a problem, formulating solutions to deal with it, and putting those solutions into practice to improve the process. Six Sigma is a powerful tool that businesses can use to reduce defects, boost quality, and enhance customer satisfaction.


3. Total Quality Management (TQM)

Total Quality Management (TQM) is a managerial approach that emphasizes continuous improvement through employee involvement to achieve customer satisfaction. TQM accentuates the significance of quality in all facets of business operations by involving the staff.

Customer focus, continuous improvement, staff involvement, leadership, process management, and data-driven decision-making are just a few of the elements that make up TQM. TQM is a powerful tool that businesses can use to raise employee engagement, increase customer satisfaction, and improve the quality of their products and services.



4. Lean Manufacturing

Lean manufacturing is a systematic strategy that aims to optimize efficiency and manage waste generation in a production process. Lean manufacturing has become a renowned strategy in recent years as it increases customer value while also reducing costs, time, and resources. Lean manufacturing relies on a quality control (QC) methodology to ensure that goods adhere to the established quality standards.

A QC strategy can be included in every step of the production process using lean manufacturing concepts like continuous improvement, root cause analysis, and visual management.


For enterprises to maintain consistent product and service quality and achieve customer satisfaction, effective standard QC methods are essential. SPC, Six Sigma, TQM, and Lean Manufacturing are four effective methodologies to support QC through quality improvement. By implementing these methodologies, manufacturers can better meet customer needs, reduce costs, and stay competitive in today's ever-changing business landscape.

Posted by Nadya Lukman

Nadya Lukman

Nadya is a Mechatronics Engineer who had worked on several different projects including PCU design, engine design, and AI image processing systems. Besides having a little bit of caffeine addiction, she enjoys reading and traveling to new places.