| 摘要 |
PROBLEM TO BE SOLVED: To prevent diffusion of dust to the outside during internal inspection work. SOLUTION: In the manhole 1 for internal inspection work arranged at a dust collector 2, an air nozzle 6 for supplying compressed air C into the dust collector 2 is arranged on the periphery of an opening part 5. An air curtain is formed by supplying compressed air C into the dust collector 2 from the nozzle 6 during internal inspection work to prevent the dust D present in the dust collector from scattering to the outside from the manhole 1. When a worker 8 comes out of the manhole 1, the dust D bonded to a working uniform or the like is shaken off by compressed air C and sent into the dust collector 2 to prevent dust D from falling to the outside of the manhole 1. |
