【正文】 existence of dangerous and harmful factors to determine the extent feasible and reasonable security countermeasures and suggestions. Such as the 2021 State Administration of Work Safety to carry out a special safety assessment of dangerous chemicals. 2. Quantify the degree of classification based on the evaluation (1) qualitative evaluation Qualitative evaluation is mainly based on experience of the production system technology, equipment, environment, personnel, management and other aspects of the security situation in qualitative judgments. Qualitative evaluation does not quantify the risk of treatment, only for qualitative parison. Qualitative evaluation using systems engineering approach to depose the system, relying on evaluation of personnel, the ability to observe and analyze, by means of the relevant regulations, standards, norms, experience and ability to judge for evaluation. Belong to this type of evaluation methods have safety checklist (Safety Check List, abbreviation SCL), prerisk analysis (Preliminary Hazard Analysis, abbreviation PHA), fault type and impact analysis (FailureMode Effects Analysis, abbreviation FMEA), risk and operability study (HazardandOperabilitySmdy abbreviation HAZOP) and other methods. Such method is characterized by simple, easy to grasp, easy to operate, the results of the evaluation process and intuitive, you can clearly express the equipment, facility or system39。 evaluation of the results depends on evaluation of the experience, the experience with a very high ponent。 description of the hazards 畢業(yè)論文 and risks of lack of depth , evaluation of objects of different types of evaluation results are not parable。 E1) evaluation method, Imperial Chemical (ICI) Richmond (Mond) division of fire, explosion, toxicity index evaluation method, the Japanese Labor Chemical six stages of plant safety evaluation method, our methods of classification of dangerous chemical safety assessment. Index method using the structure of plex systems and the use of probability is difficult to express their risk evaluation unit has a feasible method, such method is simple, more evaluation is one of the methods applied in petroleum, chemical and other areas used more often. Index used to avoid the accident and its consequences is difficult to determine the probability of the difficulties, the evaluation index value contains both accident frequency and consequences of the accident two factors. The disadvantage of this type of evaluation is to evaluate the security system model of the system function of inadequate attention, especially hazardous substances and the interaction between the security system not considered the relationship, although in Mongolia, Germany and France and China chemical plant risk classification There are certain considerations, but the deficiencies are still apparent, between the various factors to the product or additive manner, ignoring the importance of the difference between the factors. Evaluation from the beginning to use the index value is given, making the evaluation of postsafety improvements to the system more difficult. Evaluation of various indices in the current model, the value of the indicators and targets set to determine only whether or not, but not with objective indicators of factors independent of the state, resulting from a hazardous materials type and content, spatial arrangement similar to the difference between the actual level of security than remote system, the evaluation results are similar, these methods lead to less flexibility and sensitivity. 3. Content classification based on the evaluation (1) plant design safety assessment Plant design and application of new technologies, develop new products, while 畢業(yè)論文 feasibility studies for safety evaluation, planning and design stages through the evaluation of the risk factors on the control and elimination, some countries have it fixed in the form with the regulations. (2) evaluation of the effectiveness of safety management The business performance of the existing security management structure, the rate of injury, loss rate, investment returns and other systematic safety evaluation to identify the weak link, from the technical measures and security management to be improved. (3) human behavior safety evaluation Psychological state of human insecurity, and ergonomic points determine the behavior, assess their safety. (4) evaluation of safety and reliability of production equipment Equipment, devices, ponents fail, the application of safety systems engineering analysis to evaluate the safety and reliability. (5) Operating conditions evaluation Evaluation of operating environment and conditions on human health hazards. (6) risk assessment of chemical substances Evaluation of chemicals in the production, use, storage, transport, business process risks exist, and possible fire, explosion, poisoning, corrosion and other accidents, measures proposed to prevent accidents. 4. The nature of the classification based on the evaluation (1) the inherent risk assessment system Risk is inherent in the system planning, design, manufacture, installation and other factors determine the risk of the original, that the system put into operation before the existence of risk. According to the results of the inherent risk assessment, risk can be a hierarchy of systems, risk levels for different countermeasures to be taken into account in order to achieve an acceptable level. (2) practical risk assessment system Evaluation system is still mainly real risk, through the evaluation of various hazard control the distribution and status of safety management to focus on 畢業(yè)論文 strengthening the control.