How Sammy Obara used PDCA to reduce mosquito complaints in Thailand – Toyota by Toyota Book

The book, Toyota by Toyota, offers an in-depth examination of the Toyota Production System (TPS) and Lean methodologies. Authored by former Toyota employees, many of whom worked with Taiichi Ohno, the book provides insider perspectives on core TPS concepts like Kaizen (continuous improvement), Just-In-Time (JIT), Jidoka (autonomation), standardized work, and problem-solving (PDCA). It emphasizes the human element, culture of respect and humility, and the importance of hands-on learning and visible management support in successfully implementing these principles across various industries and organizational levels.

Sammy Obara’s chapter, “Problem-Solving PDCA” details a case study from Siam Toyota Manufacturing (STM) in Thailand concerning a significant mosquito infestation.

Here’s a summary of how the problem was addressed:

• Problem Identification: Employee surveys at STM revealed that 65% of employees complained about mosquitoes, making it the most significant issue, far surpassing other concerns like noise or dust.

• Team Formation: A PDCA (Plan-Do-Check-Act) team, whimsically named “Doctor Smile,” was formed. This cross-functional team included representatives from employee relations, environmental affairs, and facilities. An insect expert was consulted for a lecture and Q&A session.

• Understanding the Problem (Plan – Genchi Genbutsu):

    ◦ The team performed Genchi Genbutsu (go to the real place, see the real stuff) to thoroughly understand the problem at its point of cause.

    ◦ They investigated where mosquitoes were most common, the types of mosquitoes present, when they were most active (July to November, the rainy season), and how they bred and entered the plant.

    ◦ A sticky screen device was set up to count captured mosquitoes, which was crucial for later verifying the effectiveness of countermeasures.

• Problem Statement and Root Cause Analysis:

    ◦ The team meticulously crafted a clear, accurate, concise, and measurable problem statement to keep everyone focused.

    ◦ They applied the Five Whys technique to delve deeper into the causes, moving beyond superficial answers. This led to identifying main breeding points such as gutters and a small pond near the factory.

    ◦ Pareto charts were used to show mosquito quantities per area, helping prioritize where to tackle the problem first (attacking 20% of areas to reduce 80% of complaints). Trend charts indicated active periods. An Ishikawa (cause-effect) diagram plotted the results of their brainstorming, linking causes to the infestation.

• Implementation (Do – Trystorming):

    ◦ The team conducted mini-PDCAs or “trystorming” to test countermeasures on a small scale before full implementation.

    ◦ Examples of countermeasures included: installing fly traps at building entrances, weekly insecticide application in specific spots, and introducing fish into the pond to eat mosquito larvae. This cautious approach ensured that only effective solutions were scaled up, avoiding costly mistakes.

• Verification and Standardization (Check & Act):

    ◦ The effectiveness of the countermeasures was continuously checked. For instance, the fly traps were monitored, insecticide brands were tested in different areas, and the fish’s survival and larva-eating habits were verified.

    ◦ Once validated, the solutions were standardized (“Act” part of PDCA). This involved creating charts for insecticide application frequency and standardized instruction sheets for trap cleaning and hanging to ensure consistent application.

• Results and Recognition:

    ◦ The after-PDCA survey showed a significant reduction in complaints, from 65% to 21%.

    ◦ Toyota’s system emphasizes recognition for such projects. Rewards focused on effort and teamwork over monetary savings. Leaders, through Genchi Genbutsu and Socratic coaching, provided immediate and frequent recognition.

    ◦ The project was considered for presentation at Toyota Headquarters’ annual Kaizen and PDCA convention in Toyota City, a highly coveted form of recognition.

• Lateral Learning (Yokoten):

    ◦ The project’s findings were documented in an A3 report and shared laterally (Yokoten) with neighboring plants (e.g., electronics, engine, consumer goods manufacturers) and other Toyota sister plants globally, aiming to accelerate learning and spread best practices.

• Continuous Cycle: The PDCA cycle continued, as solving the mosquito problem elevated noise as the next major complaint, prompting a new cycle of improvement efforts.

To read the entire chapter, check out the book, Toyota by Toyota