(a) General.
(1) Vacuum test each manhole in accordance with ASTM C1244 and the following:
a. No personnel shall be allowed in manhole during testing.
b. Test manhole after assembly and prior to backfilling.
c. Plug pipes with suitably sized and rated pneumatic or mechanical pipeline plugs. Brace plugs to prevent displacement.
d. Position vacuum test head assembly to seal against interior surface of the top of cone section in accordance with manufacturer's recommendation.
e. Draw vacuum of ten inches of mercury on manhole. Shut off the vacuum pump and close valve on vacuum line.
f. Measure time for vacuum to drop to nine inches of mercury. Manhole shall pass if time meets or exceeds the following:
Manhole I.D. (inches) | 48 | 60 | 72 | 84 | 96 | 120 |
Seconds | 60 | 75 | 90 | 105 | 120 | 150 |
g. If manhole fails test, remove head assembly, coat interior with a soap and water solution, and repeat vacuum test for approximately 30 seconds. Leaking areas will have soapy bubbles. Make necessary repairs to the satisfaction of city and repeat test until manhole passes.
(Ord. of 11-7-16, No. 10-16)