求翻译：在设计之前进行安全评价，可避免选用不安全的工艺流程和危险的原材料以及不合适的设备、设施，或当必须采用时，提出降低或消除危险的有效方法。设计之后进行的评价，可查出设计中的缺陷和不足，及早采取改进和预防措施。系统建成以后运行阶段进行的系统安全评价，可了解系统的现实危险性，为进一步采取降低危险性的措施提供依据。是什么意思？

Safety assessment carried out before the design can avoid using unsafe process and dangerous raw materials, and inappropriate equipment, facilities, or must be an effective way to reduce or eliminate the danger. Design after evaluation, can identify defects and deficiencies in the design, as soon as

Before the design safety evaluation, you can avoid using unsafe processes and hazards as well as the raw material is not appropriate equipment, facilities, or when you must, by reducing or eliminating risk. After the design of the evaluation to identify weaknesses in the design and not enough, take

Before design carries on the safety evaluation, may avoid selecting the unsafe technical process and dangerous raw material as well as the inappropriate equipment, the facility, or when must use, proposed reduces or the elimination danger effective method.The design carries on afterwards the apprais

Before the design safety evaluation, you can avoid using insecure processes and hazardous materials, and without the right equipment, facilities, or when you must, make effective methods to reduce or eliminate the risk. After the design of evaluations, to identify gaps and deficiencies in the design