Any person whose duties require him to enter a manhole, or who allows another under his supervision to do so, without having a person act as a guard at the entrance to the manhole, or who violates any rules or regulations of the Department of Labor and Industry promulgated pursuant to this act, shall, upon summary conviction, be sentenced to pay a fine of not less than ten dollars ($10) and not more than fifty dollars ($50), and, in default of the payment thereof, undergo imprisonment for a period not exceeding ten days.