其二，对事故致因理论、预先危险分析法以及故障树分析法进行了介绍及改进，

Second, the accident causing theory, Preliminary Hazard Analysis and Fault Tree Analysis and improvements were introduced, and apply it to the construction site safety management systems, completed a closed-end management of construction site safety. <br>Third, the use of an accident causing theory of factors that could cause accidents analyzed and identification, using both A Method for Risk Assessment (MES) risk assessment method factors quantization process, the above work is completed, for reasonable security program, improve construction site safety management system has played a very valuable scientific reference.

Second, the accident cause theory, pre-danger analysis method and fault tree analysis method are introduced and improved, and applied to the construction site safety management system, completed the closed management of the safety of the construction site.<br>Third, the factors that may cause accidents are analyzed and identified by using the accident cause theory, and the factors of The A Method for Risk Assessment (MES) risk assessment method are quantified, and through the completion of the above work, a reasonable safety plan is formulated. Perfecting the safety management system of the construction site has played a very valuable scientific reference role.

Secondly, it introduces and improves the accident cause theory, pre hazard analysis method and fault tree analysis method, and applies them to the construction site safety management system to complete the closed management of the construction site safety.<br>Thirdly, using the theory of accident cause to analyze and identify the factors that may lead to the accident, and using a method for risk assessment (MES) to quantify the factors, through the completion of the above work, it has played a very valuable scientific reference role in formulating a reasonable safety plan and improving the safety management system of the construction site.