(a) A fee of $135.00 per hour, and for work performed after 5 PM on Monday through Friday or at any time on Saturday, Sunday and on a State holiday a fee of $ 202.50 per hour, or part thereof, including travel time as set forth in part (1) of this subsection, based on quarter hour intervals, with a minimum of one-half hour, shall be charged for all shop, field erection and resale inspections of al