At present, the common systems include quality management system, environmental management system, food safety management system and occupational health management system. If you want to be the internal auditor of that system, you must attend the training of that system. The training time is usually 3-4 days, and the cost varies from place to place, usually several hundred to one thousand. If you really want to learn the standard well, it is recommended to go to a regular large-scale training institution. You can find the registration agency at CNAS. Generally, every city has such institutions. Please consult the training time again.
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