When an employer has obtained the permission from the Director of the Labor Standards Office Concerned according to Form No. 11 with respect to the time between the commencement and completion of the entry into a pit for workers who enter and exit a pit as a group, the time period between the completion of entry into and the completion of exit from a pit shall be deemed as working hours of workers belonging to the group for the purpose of the application of the provisions of paragraph (2) of Article 38 of the Act.