Why do some people pass the civil service physical examination but fail the occupational health examination?

Some people can pass the civil service physical examination, but the occupational health examination fails because of different standards. The physical examination of civil servants mainly focuses on the examination of basic health conditions such as internal medicine, surgery, ent and gynecology; Occupational health examination includes internal medicine, surgery, ENT, gynecology, electrocardiogram, abdominal B-ultrasound, chest X-ray and so on. Different standards lead to civil servants passing the physical examination, but failing the occupational health examination.