Unionized subway employees who work on a portion of Seoul’s line number nine launched a three-day strike on Monday. 

The Korean Confederation of Trade Unions(KCTU), the umbrella organization that represents the workers’ union, says the strike will affect a 13-station section between Eeonju station and VHS Medical Center in southeast Seoul.

KCTU said subway train operations in this section will run as normal between 7 and 9 a.m., but will be scaled back to 80 percent between 5 and 7 p.m. and to 60 percent during the remaining hours.

The umbrella organization added such a decision was made given that subways are a public workplace that require essential maintenance under related laws.

However, subway passengers are unlikely to face major disruptions given that the Seoul Metropolitan Government and Seoul Metro will deploy substitute workers to maintain normal line nine operations.

The union workers are seeking to replace the annual salary system with a salary step system, an expansion of personnel and to turn four non-regular security personnel into regular employees.