Confined space manhole sign system
US5842811A · kind A · utility
Inventor
Key dates
| Filing date | Feb 21, 1997 |
| Grant date | Dec 1, 1998 |
| Priority date | — |
| Expiry date | Feb 21, 2017 |
Classification
- Technology area (CPC E)Fixed Constructions
- CPC primaryE02D2300/0006
- WIPO fieldCivil engineering
- WIPO sectorOther fields
Abstract
A confined space manhole sign system for use in association with a manhole including a ledge and a manhole cover, the apparatus comprises a plurality of manhole insert members each having a circular base with an upper surface, an upstanding sidewall extending from the base and being formed contiguously therewith, two drain apertures being positioned at the intersection of the base and the sidewall, a flange being formed contiguously with the upstanding sidewall and extending radially therefrom, the flange having a lower surface including a plurality of perforation grooves formed therein; and a plurality of warning signs each having descriptive indicia marked thereupon, each of the warning signs being fixedly positionable upon the upper surface of the base, the system warning manhole workers of potentially dangerous situations within a manhole.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.