A survey of businesses that hire part-time teenage workers has found that more than two-thirds violate labor laws.

Labor law breaches were found at 69 percent of the 939 employers surveyed. Nearly 1,500 violations were found, including delayed payment and paying below minimum wage, according to the Ministry of Employment and Labor’s survey, which was held from Jan. 15-Feb. 8 and released Sunday.

Businesses that do not specify working conditions in labor contracts made up the largest share, at 41.5 percent.

Delayed payment of wages was also common, standing at 27.4 percent. More than 11 percent of the businesses did not pay teenagers the minimum hourly wage of 5,210 won ($4.87).

The violations were made by 686 branches of popular coffee, fast food and convenience store franchises.

The convenience stores in question include CU, 7-Eleven, GS25 and Ministop outlets, while fast food violators included branches of Mr. Pizza, Domino’s Pizza and Pizza Etang.

Branches of Ediya Coffee, Holly’s Coffee and Starbucks were also included on the list.

The Ministry of Employment and Labor vowed to require violators pay a total of 157 million won in unpaid wages to employees, while those caught by the ministry more than twice in the past year are subject to punishment.

“The ministry will supervise franchise stores to maintain appropriate working conditions for teenagers,” Lim Moo-sung of the ministry’s labor policy department said.

By Suk Gee-hyun (monicasuk@heraldcorp.com)