Root Causes Archives - understand-culture

Automation with a Human Touch

In the Toyota Production System, jidōka is written 自働化, not 自動化, the usual word for automation. Toyota calls it ninben no tsuita jidōka, automation with the person radical added to the character. It means automation with human wisdom added.

Toyota traces the idea to the automatic loom invented by Toyoda Sakichi. The loom did more than mechanize work once done by hand. It had a built-in device that let the machine judge good from bad. An article in the engineering news site MONOist sets the two side by side: stopping when a thread breaks, and stopping when anything is abnormal.

Medical Accident Investigations

Since October 2015, Japanese hospitals have investigated medical accidents under the iryō jiko chōsa seido, the medical accident investigation system. The Ministry of Health, Labour and Welfare says the system aims to prevent recurrence and secure the safety of medical care. A national support center collects and analyzes the hospitals’ investigations.

Fukushima Prefecture’s guide to the system adds that it is “not intended to pursue the responsibility of individuals.”

Reviewing the Game Together

In professional shogi, the two players usually examine the game together after it ends. This review is called kansōsen, the battle of impressions. Winner and loser both take part.

Day-Shift Education

On April 25, 2005, a JR West train derailed on the Fukuchiyama Line, and 107 people died, 106 passengers and the driver. Earlier in the run, the train had overshot its stopping position at Itami Station by about 72 meters and arrived there about one minute and eight seconds late.

JR West had a practice called nikkin kyōiku, day-shift education. After an incident, a crew member could be moved to day duty and retrained. The Kobe Shimbun calls it punitive training. It writes that the investigators’ report suggests that the driver may have been under pressure from the nikkin kyōiku he had been through.

Near Misses

Hiyari hatto is the experience of a situation that could have led to an accident, or the discovery of such a situation.

Japanese guides to workplace safety explain it together with Heinrich’s law. Behind one serious accident lie 29 minor accidents, and behind those lie 300 irregularities.

The Andon

On a Toyota assembly line, a worker who notices a problem activates the andon and calls a supervisor. If the problem can be fixed on the spot, the line keeps running. If not, the line stops at a set position.

The system rests on three conditions. A worker can call. When someone calls, a person always comes. The person who called is not blamed.

Hidden Recalls

In 2000, it became known that Mitsubishi Motors had hidden defect reports from customers and repaired vehicles in secret.

On January 10, 2002, a wheel came off a Mitsubishi truck in Yokohama and struck a mother and her two children. The mother, 29, died. The company blamed poor maintenance. In March 2004, it withdrew that explanation and announced a recall. In April 2004, police arrested seven former top executives of Mitsubishi Motors and Mitsubishi Fuso.

Five Whys

Taiichi Ohno, the former Toyota vice president regarded as the father of the Toyota Production System, published Toyota Seisan Hōshiki in 1978. In it he wrote that by asking why five times and answering each time, one can find the chain of cause and effect and the real cause hidden behind a problem.

Toyota employees are drilled in the method from their first days as new hires.

Failure Knowledge Database

On March 27, 2003, the Japan Science and Technology Agency released a trial version of its Failure Knowledge Database. It held about 560 cases of accidents and failures in four fields of science and technology.

The project collected and analyzed such cases and organized their lessons as knowledge to be shared. It was supervised by the engineering professor Hatamura Yōtarō.

Japan Transport Safety Board

The Japan Transport Safety Board investigates aircraft, railway and marine accidents. Article 1 of the law that set it up states its purpose. The board investigates the causes of accidents and of the damage they cause, and asks for measures based on its results, in order to help prevent accidents.

Article 18 adds that the board’s investigative powers must not be interpreted as granted for criminal investigation.