Shorter working hours kicked off nationwide Monday, testing both the competiveness and productivity of Korea Inc., which has long relied on a workforce that puts in long hours for its dramatic growth.

Marking a significant change in the nation’s labor market, after the five-day workweek was adopted in 2004, the new system requires workers to work less than 52 hours a week. It has taken effect for large businesses with more than 300 employees for now. Smaller businesses with fewer than 300 workers should implement the system starting Jan. 1, 2020, while financial, media and postal companies have been granted a yearlong grace period to avoid market confusion.

If the rules of keeping employees’ workweek under 52 hours are violated, a business owner could face up to two years in prison or a fine of up to 20 million won ($18,000). A survey conducted by the Labor Ministry on 3,627 businesses with more than 300 workers showed that 59 percent had already enforced the maximum 52-hour workweek.

On its first day, there were both expectations for better work-life balance and concerns of industries losing their strengths across the corporate world.

Samsung Electronics and its subsidiaries have adopted a new system that allows workers to design their work schedule and make flexible choices for their office hours.

Steel giant Posco implemented a dual-work system for office workers and engineers at its plants, an official said.

From now on, workers at Posco’s offices can choose to submit a one-month work-hour plan in advance and consult with their supervisors to prevent a void in operations, while engineers at plants can also choose to schedule their work hours on a three-month basis so that they work more flexibly at steel mills operating 24-hours a day.

“What we can expect from the new system is work-life balance,” said the Posco official. “We could at least schedule something for ourselves later in the evening that could, in return, invigorate our energy for work,” he said.

No drastic change is expected at the offices of carmakers Hyundai and Kia, as they implemented an 8-to-5 work system years ago. But they will better manage the working hours of office workers to make sure they do not work extra hours, officials said.

Amid growing calls for work-life balance, companies have been seeking a change in the work culture that has considered workers spending long hours at the office as a sign of loyalty.

For companies, a change in the traditional work culture is necessary, as the shorter workweek means they have to hire more. Posco, for instance, plans to hire 500, in addition to its existing plan of 1,000 new jobs a year.

Experts say the shorter workweek will result in a new work culture in order to maximize efficiency in shorter hours and spend less time on corporate bonding events like company dinners. To do so, Korean conglomerates may have to go through massive reforms in the work culture built on a hierarchical system, they said.

Still, skepticism remains toward the new system, with some saying it is not enough to change the existing culture.

“I doubt it. How could a sales person win a contract without having a long dinner with his or her clients in this market that regards close relationships as the basis of trust,” said Young Cho, a worker in Seoul.

By Cho Chung-un (christory@heraldcorp.com)