When signs are erected giving notice thereof, no person shall operate any commercial vehicle exceeding 14,000 pounds gross weight at any time upon any of the streets or parts of streets not described in Schedule VII, PMC 10.80.040, except that such vehicle may be operated thereon for the purpose of delivering or picking up materials or merchandise and then only by entering such street at the intersection nearest the destination of the vehicle and proceeding thereon no farther than the nearest intersection thereafter. [Code 1970 § 10.64.020; Code 1954 § 8-38.08.]