地下管道疏通作业中有时尽管采取了积极措施，但仍会有一些不安全因素无法排除。按规定穿戴好各种防护用品就可以避免这些危险因素对人的伤害。在作业中，主要是要正确佩戴防毒面具，以防中毒。如前所述，下水管道一旦被管道疏通开，积聚在管道的硫化氢、甲烷和一氧化碳有毒气体会突然冲出井口。
Although some active measures have been taken in the dredging operation of underground pipelines, there are still some unsafe factors that cannot be excluded. Wearing all kinds of protective equipment according to the regulations can avoid the harm of these risk factors to people. In the operation, the main thing is to correctly wear gas masks to prevent poisoning. As mentioned before, once the sewer pipeline is dredged, the toxic gas of hydrogen sulfide, methane and carbon monoxide accumulated in the pipeline will suddenly rush out of the wellhead.
此时毒气浓度很大，必须佩戴长管面具、氧气呼吸器等隔离式防毒面具。尤其当发现作业人员已经中毒时，抢救人员更应戴好隔离式防毒面具再救人。决不能因救人心切，就忘记戴防毒面具或只戴过滤式防毒面具。结果使施救人员也受到伤害，清洗管道扩大中毒事故的人员伤亡和损失。
At this time, the concentration of the gas is very high, so long pipe mask, oxygen respirator and other isolation gas masks must be worn. Especially when it is found that the operators have been poisoned, the rescuers should wear isolation type gas masks to save people. Never forget to wear gas mask or only filter gas mask because you are eager to save people. As a result, the rescuers were also injured, and the pipeline cleaning expanded the casualties and losses of poisoning accidents.