The JJF 1273-2011 standard applies to the calibrating of AC, DC (including half-wave rectifier and full-wave rectifier) magnetic particle flaw detectors, but does not apply to electromagnetic yoke flaw detectors or swirl/spin magnetic field flaw detectors. Citing relevant Measurement terms and equipment standards, the specification defines the concepts of circumferential and longitudinal magnetizing currents, which are used to detect longitudinal and transverse defects in workpieces, respectively. Magnetic particle flaw detectors reveal the location, size, shape and severity of defects by applying magnetic particles to the surface of the workpiece. Flaw detectors are divided into fixed and mobile types. Fixed equipment can generate a variety of magnetizing currents, while mobile types usually have only a single current loop. This specification provides calibration methods to ensure equipment accuracy and Reliability to improve the accuracy and effectiveness of nondestructive testing.