According to the 2018 Labor Force Survey by the Ministry of Internal Affairs and Communications, the percentage of people working 49 hours or more per week was 11.5% in the UK, 10.1% in France, and 8.1% in Germany, while in Japan it was 19.0%. Thus, compared to other countries, Japan tends to have longer average working hours.

The manufacturing sector, which accounts for 20% of GDP, is no exception, with long working hours and excessive overtime being major concerns.

This time, we'll introduce the causes of increased overtime work in factories and five main solutions.

1. Reasons why overtime work increases in factories

First, let's examine the reasons behind the increase in overtime work at factories.

Labor shortage in the manufacturing sector

As Japan's working population declines due to its low birthrate and aging population, the number and proportion of young workers (under 34 years old) in the manufacturing sector are also steadily decreasing, leading to a worsening labor shortage.

This trend is particularly pronounced among small and medium-sized enterprises with fewer than 300 employees, and has been on a long-term downward trend. The White Paper on Manufacturing (2019) revealed that the number of new graduates entering the manufacturing industry, which was over 100,000 in 2000, had fallen to less than 60,000 in 2016.

When there is a shortage of labor, the workload on each person increases, and more people end up working overtime to finish tasks that cannot be completed within regular hours.

A culture where overtime is considered normal.

While overtime hours in Japan have gradually decreased since the bubble economy era, many of those who worked during that time still view overtime positively.

When there are supervisors who are not opposed to overtime, more employees feel reluctant to leave work due to the workplace atmosphere, which can become one of the factors contributing to chronic overtime.

We do not know our production capacity.

Not understanding the current production capacity of the factory can lead to overtime work.

For example, if a factory can produce 100 cars a day and receives an order for 100 cars a day, the order quantity is considered to be in line with its production capacity. However, if the order increases to 120 cars a day, the only way to compensate for the 20 cars that exceed production capacity is through overtime work.

If production capacity is known, measures can be taken to avoid accepting orders that exceed production capacity, or to increase production capacity by improving work efficiency. However, operating without knowing production capacity can lead to overtime work.

They evaluate work based on working hours.

In Japan, the adoption of discretionary work systems is not widespread, and the system of paying wages based on working hours is common. Especially in factories, where productivity per hour is easy to measure, a system of evaluating an employee's work based on working hours has become established.

As a result, companies fail to develop systems for evaluating employees' work outside of working hours. This leads to a situation where employees are judged as contributing more to the company the more overtime they work, and consequently, more employees voluntarily work overtime.

Business processes are not transparent.

When there are tasks that only certain employees can do, it increases the burden on those specific employees, which ultimately leads to increased overtime.

By identifying which employees are performing which tasks and "making work visible," managers can distribute work within teams, preventing work from becoming concentrated on specific employees.

On the other hand, if the "invisibility of work" is left unaddressed, it can lead to an increase in the workload for each individual, potentially resulting in inefficient overtime.

2. Five ways to reduce overtime

So, what specific methods can be used to reduce overtime in factories? Here are five main methods that can be implemented in factories.

Thoroughly implement 5S

5S activities, used to improve the factory environment, also help reduce overtime. 5S stands for Sort, Set in order, Shine, Standardize, and Sustain, and refers to the following initiatives:

・Organize: Classify parts and tools, and dispose of anything that is not needed.
・Organization: Arrange parts and tools so they are easy to access.
• Cleaning: Maintain a clean state through cleaning.
• Cleanliness: Organize, tidy up, and clean daily.
• Discipline: Share the importance of organization, tidiness, cleaning, and cleanliness with employees.

Thorough implementation of 5S activities helps eliminate waste in the workplace and work processes, leading to increased work efficiency.

To implement 5S activities more effectively, it's a good idea to designate a leader to conduct regular factory inspections. Questions raised during inspections, such as "Why is it arranged this way?" or "Why isn't it categorized?", can lead to the discovery of long-standing inefficient habits and waste.

Multi-skilled workers

Multiskilling refers to developing multiple skills, where an individual is trained to perform multiple tasks rather than being assigned to just one.

In a system where each employee performs only one task ("single-skilled worker"), the types of work they can do become uneven, leading to an excessive burden on some employees. This can result in work being concentrated on specific departments or individuals depending on the project, and create disparities in overtime hours among employees.

By promoting multi-skilling, the workload among employees becomes more equitable, and the amount of overtime per person can be reduced.

Make them report their overtime to their supervisor.

A system requiring prior notification of overtime is also effective in reducing overtime work. If you need to work overtime, you should submit an application form containing the following information to your supervisor.

Reasons for working overtime
• Planned overtime hours
・Overtime details

Managers should review these details to determine if overtime is necessary and, if not, instruct employees to carry over the work to the following day. Additionally, compiling these application details to understand which departments are working overtime, for what reasons, and to what extent can be used to inform efforts to reduce overtime.

Create a no-overtime day.

According to a 2011 survey conducted by the Ministry of Health, Labour and Welfare on actual working hours per month, 15.5% of companies that did not implement no-overtime days had actual working hours of less than 160 hours, compared to 27.7% of companies that did. This shows that companies that introduced no-overtime days had shorter actual working hours.

A "no overtime day" is an initiative to designate a specific day of the week when overtime is prohibited. However, instead of setting a company-wide rule for this day, allowing employees to choose their own no-overtime day makes it easier for them to leave work without worrying about their colleagues, thus increasing its effectiveness.

In addition, by allowing employees to share their no-overtime days with each other, teams can coordinate to avoid overlaps, minimizing the impact on work.

Incorporate working hours into performance evaluations.

Incorporating guidelines for overtime hours and initiatives for work improvement into the performance evaluation system can raise employees' awareness of reducing overtime work and is effective in improving overtime hours.

Furthermore, by incorporating items related to subordinates' overtime work into the evaluation criteria for managers, it becomes possible to improve work efficiency through a top-down approach, which leads to the appropriate management of overtime work.

3. Implement initiatives that are appropriate for your factory.

This time, we've introduced the main reasons for the increase in overtime, but it's impossible to generalize because each factory has different production systems, personnel, and challenges.

First, identify the challenges facing your own factory and then implement solutions that are appropriate for those challenges.

４．まとめ

Japan tends to have longer working hours compared to other countries, and the manufacturing sector is no exception.

Factories tend to experience chronic overtime due to factors such as labor shortages and the evaluation of work based on working hours.

To solve this problem, effective measures include thoroughly implementing 5S, multi-skilling workers, an overtime application system, no-overtime days, and improvements to performance evaluations. However, since the causes of overtime vary from factory to factory, it is important to thoroughly understand the current situation at your own factory before working to reduce overtime.