Introduction Pre-Construction Standard Installation Installations Considerations Post-Construction References
Visual inspection
Infiltrations & Exfiltration
Air Testing
Deflection Testing
Test Yourself
If considered necessary, pipe deflection can be tested within 30 days of installation by pulling a mandrel through the installed pipe. Testing 10% of the overall project should provide a reasonable indication of installation quality. Typical practice is to set mandrels at 7.5% of the base inside diameter as shown in the following table. Mandrel test yield only pass/fail results and can provide misleading information. Further investigation should take place to ensure the problem is not being caused by, a foreign material in the pipe, a slightly offset joint, or some other similar situation.

Nominal Pipe Diameter (in.) Base Inside Diameter (in.) Base Inside Diameter with 7.5% Deflection (in.)
4 3.86 3.57
6 5.81 5.37
8 7.65 7.08
10 9.59 8.87
12 11.63 10.76
15 14.51 13.42
18 17.45 16.14
24 23.22 21.48
30 29.05 26.87
36 34.80 32.19
42 40.09 37.08
48 46.09 42.64
54 51.47 47.61
60 57.62 53.30
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