| 摘要 |
A retractable safety post for facilitating access in and out of a manhole is slidably attached to each side rail of a wall-mounted ladder. Each post slides within a tubular sleeve fixed to the side rail and is selectively movable between a retracted or stowed position to an extended or use position. Each post has at its upper end a ca p and handle for ease of grasping during use, and at its lower end a latch member for securing the post in its extended position during use. A wall bracket anchoring the ladder to the manhole serves as a resting support for the latch member and its post when in the extended position. The post is secured in the extended position by merely lifting the post, twisting the post a given amount in a pre-set direction, and lowering the post slight ly so that the latch member can engage the wall bracket. In its stowed position, the post rests wholly within the manhole.
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