(a) Maintenance. A thorough examination of the fire extinguisher done in accordance with the manufacturer's written instructions and the requirements of this chapter. It is intended to give maximum assurance that a fire extinguisher will operate effectively and safely. Maintenance includes a thorough examination and any necessary repair or replacement. Maintenace will normally reveal if hydrostatic testing or internal maintenance is required.

(b) Master Gauge, Low Pressure Test Equipment. A master gauge is a pressure indicating device that is used as a calibration standard and has an inherent accuracy equal to or better than the requirement for the pressure indicating device being verified. Master gauge calibration shall comply with the Section 12500 of the California Business and Profession Code by a third party using a dead weight test device or an electronic pressure measuring device of appropriate accuracy. A master gauge shall not be used as a pressure indicating device.

(c) Marketing. The act of selling. [See Section 557.19 (a)].

(d) Mild steel shell. Except for stainless steel and steel used for high pressure cylinders, all other steel shells are defined as “mild steel” shells.