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equipment, or the equipment will have certain safety constraints in place. Personnel handling the radiography machine will have ample training and know the functions of the equipment. Hydrostatic Test According to DOE-HDBK-1017/1-93, during hydrostatic testing, minimum pressurization temperature precautions include making sure that the desired hydrostatic pressure is consistent with plant temperatures so that excessive stress does not occur. Load Test Load testing uses a machine at high pressures. This machine should be well maintained to prevent any possible accidents. The operator should wear goggles and understand the operation of the machine. Personnel should keep a safe distance from equipment during use. e. Identify the special hazards that are associated with radiographic testing and discuss how they are mitigated. The following is taken from NASA, “Radiographic Testing of Aerospace Materials.”Radiography constitutes a health hazard that requires special radiation training for personnel involved with its use. Also, adequate safety devices should be built into the x-ray facility, including safety interlock switches keylock system radiation monitoring device
236 warning system adequate facility shielding At least one qualified operator plus a radiation protection supervisor or designated alternate must be present at all times during any x-ray operation. The personnel requiring access to the x-ray area must be monitored to ensure that no one absorbs excessive amounts of radiation. The normal means for monitoring radiation is to wear pocket dosimeters and film badges. The dosimeter is read and recorded daily and usually the film badge is developed and read at least quarterly. Both devices are compared and should check within 20 percent of each other. The allowable dose of radiation is 1.25 roentgen equivalent man (rem) per quarter year. For added safety, each time the x-ray area is entered a survey meter should be used to ensure that the area is safe to enter. Interpretation of radiographs requires highly trained and qualified technicians who must 1) define the quality of the radiographic image, which requires a critical analysis of the radiographic procedure and the image developing procedure; 2) analyze the image to determine the nature and extent of any abnormal condition in the test piece; 3) evaluate the test piece by comparing interpreted information with standards or specifications; and (4) report inspection results accurately and clearly. f. Identify the special qualifications needed by technicians performing each of the listed test and inspection techniques and discuss how those qualifications are achieved. The following is taken from the NDT (nondestructive testing) Resource Center. Nondestructive testing personnel are often certified by their employer or other agency to meet certain qualifications, which are established by industry. Certification is basically a process of providing written testimony that an individual is qualified to do certain work. The qualifications