Pipeline flaw detection is divided into many kinds. Magnetic flaw detection is not harmful, if it is X-ray or isotope irradiation, belongs to radiation damage, radiation damage will cause hematopoietic damage, central nervous system damage and gastrointestinal damage, etc. 1. 1. hematopoietic system damage: will damage the bone marrow, spleen, lymph nodes and other blood cells generated by the hematopoietic organs. 2 ~ 10Gy radiation can appear after loss of appetite, nausea and vomiting, etc. When the symptoms are relatively stable, the lymph nodes and other organs can be damaged. When symptoms are relatively stable, hematopoietic cells in the lymph nodes, spleen and bone marrow begin to decrease, resulting in a severe shortage of red and white blood cells. Infection-fighting leukopenia can lead to severe infections. 2. Central nervous system damage: caused by exposure to ultra-high doses of radiation. Usually life-threatening. The first symptoms are nausea and vomiting, followed by fatigue, drowsiness and even coma. These symptoms are much like encephalitis. Tremors, spasms, ataxia and death can occur within a few hours. 3. Gastrointestinal damage: Severe nausea, vomiting and diarrhea caused by radiation in excess of 4 Gy leads to severe water loss. X-ray probing or isotope probing will not last 20 minutes. Only intermittent probing can be performed, so there will be no continuous exposure to X-rays or isotopes for 20 minutes in the field. In the case of X-ray or isotope exposure, the hazards described above would result.