TEXT VERSION OF SLIDE:
Title: Code Requirements
Type: Text and Image Slide
- City codes require a vacuum test - must maintain 10 inches of mercury for a specific time based on depth of manhole
- If vacuum test fails, then sections of the manhole must be grouted to get a better seal
- As stated earlier, there were 6 employees on site the day of the accident. 5 of the employees were working over the hill laying sewer pipe. The victim was assigned the job of grouting.
- Each manhole, per city codes, must pass a leak test, which is accomplished by pulling a vacuum and the manhole must hold a vacuum of 10 inches of mercury for a set time based on the depth of the manhole.
- This slide shows the vacuum test equipment. The upper photo shows the apparatus which seals the top of the manhole and the vacuum pump. The lower photo shows the plug inserts which are placed in the sewer pipe entering the bottom of the manhole and completes the sealed space.
- If this test fails, as in this case, someone has to grout the seams of the manhole sections.
[Images of vacuum test equipment, including manhole seal, vacuum pump, and plug inserts.]