Issues regarding fan ventilation during the cleaning and maintenance of underground channels
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I have a question: the factory has an underground trench, which is usually filled with sand; it has only one access passage that leads down from the top, as well as a manhole, and there’s also a vent valve. If an underground trench needs to be cleaned or repaired for internal work, how is the issue of air replacement in the trench generally addressed? What I’m thinking is to use a fan to blow air in through the manhole and then expel it through the breathing valve; perhaps blowing for an hour will be enough to make the air inside suitable for people to enter and work there I wonder if this method will result in incomplete air replacement in the container on the side without a vent, creating dead zones? :o
It is recommended to first use nitrogen through a hose to be introduced directly to the bottom of the underground tank in order to displace the flammable and toxic gases present there; thereafter, compressed air can be used in a similar manner for displacement, until the oxygen level in the tank meets the required standards. To prevent dead zones, the position of the hose tip can be moved intermittently.
It is recommended to conduct an analysis of combustible gases and oxygen levels after the replacement is complete, and to have a breathing apparatus available as a backup during work.
Okay, thank you! I usually only work in design and don’t know much about actual production processes; I’ve learned a lot from this
Young man, first test the internal gas, and then develop a detailed plan. Can nitrogen ensure that all dead corners are filled? Test first, then replace, test again, insert the movable CBA into the slot, and finally clean it up. Are your first-aid plans ready once the personnel have entered? A series of questions, such as wait
Young man, first test the internal gas, and then develop a detailed plan. Can nitrogen ensure that all dead corners are filled? Test first, then replace, test again, insert the movable CBA into the slot, and finally clean it up. Are your first-aid plans ready once the personnel have entered? A series of questions, such as wait
The fan is used for forced ventilation; once the sample analysis shows satisfactory results, the operator wears a breathing tube and appropriate personal protective equipment.
It is recommended to perform replacement first, followed by an oxygen content analysis; it is best to use a long-length respirator during the operation as a precaution