铁路既有隧道维修施工作业急性职业中毒对策研究

Countermeasures against acute occupational poisoning in maintenance construction of existing railway tunnel

目的根据3种不同隧道施工模式中一氧化碳、氮氧化物浓度情况,提出风险等级、危险分析关键控制点(HACCP)项点及针对性防护措施,最大限度地避免急性职业危害事故的发生。方法选取昆明铁路局单线隧道施工为研究对象,在施工过程中对工人工作位置设置检测点进行一氧化碳、二氧化氮浓度检测,对不同施工模式检测数据进行t检验。按照3种不同施工组织模式中一氧化碳浓度情况划分风险等级,根据HACCP原理找出风险关键项点,制定针对性措施。结果 3种施工模式(捣固、清筛、换轨)正常施工中,二氧化氮浓度从高到低依次为人工清筛、换轨、捣固,均符合国家卫生标准。而一氧化碳浓度从高到低依次为换轨、人工清筛、捣固施工,换轨施工一氧化碳浓度超过国家标准限值4～12倍,人工清筛一氧化碳浓度超过国家标准限值2倍,捣固施工一氧化碳浓度符合国家标准限值。结论隧道单纯捣固施工属于低风险作业,不易引起急性一氧化碳职业中毒;人工清筛作业属于中等风险作业,可能引起急性一氧化碳职业中毒,HACCP关键项点是管理好发电机和同时进入隧道的机车数量;隧道换轨作业属于高风险作业,极易发生急性一氧化碳职业中毒,HACCP关键项点是管理好小型螺栓机及发电机。对3种施工按风险等级从组织管理、人员、设备及防护4个方面对HACCP环节进行职业病危害防护,避免发生急性职业中毒事故。

[Objective]According to the concentrations of carbon monoxide and nitrogen oxides in railway tunnels under 3 construction modes to put forward HACCP and targeted control measures,and make maximum avoidance of acute professional accident.[Methods]The construction of single track tunnel by Kunming Railway Bureau was selected as study object.The concentrations of carbon monoxide,nitrogen dioxide were monitored in the operation spots during construction process,and the data of different construction modes were carried out t test.The risk grade of the 3 kinds of construction was classified on the nitrogen dioxide concentration,and the risk control points were identified on the HACCP principles to develop control measure.[Results]Under the normal construction of 3 different modes,the concentrations of nitrogen dioxide in descending order were artificial ballast cleaning,tamping and track replacement,all meeting national standard;while the concentrations of carbon monoxide in descending order were track replacement,artificial ballast cleaning and artificial ballast cleaning,the concentrations of carbon monoxide in track replacement exceeded 4-12 times of national limits,artificial ballast cleaning over 2 times,but tamping within the national limit.[Conclusion]The simple tamping construction in tunnel belongs to low-risk operation which is unlikely to cause acute carbon monoxide poisoning.Artificial ballast cleaning belongs to medium-risk operation which may cause acute poisoning of carbon monoxide;the key control point by HACCP is to manage generators and the number of locomotives entering into the tunnel simultaneously.Track replacement belongs to high-risk operation which is easy to cause acute carbon monoxide poisoning;the key control point by HACCP is to manage small bolt machine and generators.The occupational protection on HACCP control points in 3 construction mode based on risk grade from the aspects of organization and management,worker,equipment and protection is aimed to avoid the occurrence of acute occupational poisoning accident.