Our laboratory adheres to the quality concept and policy of “Justice, Science and accuracy”: strictly following the principle of national standards, adhering to the scientific development route of continuous innovation and exploration, and constantly improving the laboratory technical capacity, expand the service network, continuous improvement, build a service innovation, high-quality personnel, management science, advanced equipment, service quality of a comprehensive laboratory. In order to guarantee the reliability of the test results, the laboratory implements the strict quality control method, including two parts: The quality control in the laboratory and the quality control between the laboratories. Laboratory control includes blank test, check of calibration curve, calibration of instrument and equipment, parallel sample analysis, add-sample analysis and use of quality control chart. It is the process by which the laboratory analyst exercises self-control over the testing process. Inter-laboratory quality control includes the distribution of standard samples to evaluate the analytical results of various laboratories, the verification of analytical methods by cooperative experiments, and the examination of encrypted samples. It is an important measure to find and eliminate systematic errors between laboratories.