A. It is unlawful for any person, firm, or corporation in the city to buy any commodity upon the basis of weight or measure unless the same is brought upon the basis of the true net weight or measure, and unless the scales or measures so used bear the seal of a sealer of weights and measures and conform to the standards adopted by the city.

B. It is unlawful for any vendor, or his servant, agent, or other employee in the city to offer to sell, or sell and deliver, any commodity ordinarily and usually sold in bulk or quantity by weight or measure unless the same is weighed or measured, as the case may be, upon or by officially tested and approved weights, measures, scales, scale beams, patent balances, steelyards, automatic or computing scales, or other instruments for weighing or measuring, and unless that portion of such commodity so offered for sale or sold by weight or measure is the true net weight or measure. [Code 1980 at § 15.58.030].