The board has jurisdiction over and shall make provision for inspection of plumbing installations or alterations to public buildings and installations in newly constructed dwelling units, except as provided in this section. Political subdivisions may provide for inspection of plumbing work done within their jurisdictional limits. The board may charge the person responsible for the installation a reasonable fee not to exceed the cost of inspection. No inspection is required for any repair work or plumbing fixture replacement which requires only minor alteration, or to buildings that are not connected to a public system of waterworks or sewerage, and does not apply to maintenance work conducted by regularly employed maintenance personnel on the business premises of their employer.