| 摘要 |
PROBLEM TO BE SOLVED: To provide a ladder auxiliary device for a manhole allowing a worker to enter and exit the manhole at reasonable attitude and having a function that informs a third party of the fact that the manhole is opened. SOLUTION: This ladder auxiliary device for a manhole is provided with a pair of support pipes 3 fixed in the longitudinal direction, respectively, a pair of handrail rods 6 in which longitudinal rod parts 4 are slidably and turnably inserted into the support pipes 3, respectively, and upper parts of the longitudinal rod parts 4 are folded back in substantially U shape to form a handrail frame 5, and a fixing member 9 stretched detachably between extension end parts 8 of the handrail rods 6 to fix the extension end parts 8 mutually, on both sides of a ladder main body 2 in an upper part provided on a peripheral wall 1a of the manhole 1. The handrail rods 6 can be installed outside of the manhole 1 by raising and rotating the extension end parts 8 on the manhole 1 and bringing them into contact with a peripheral fringe part 1b of the manhole.
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