Corrugation is measured in square feet (square meters) of surface area. The mean elevation difference between the ridges and valleys of the corrugations indicates the level of severity. To determine the mean elevation difference, a 10 ft. (3-m) straightedge should be placed perpendicular to the corrugations so that the depth of the valleys can be measured in inches (millimeters). The mean depth is calculated from five such measurements.
|
Severity |
Runways and High-Speed Taxiways |
Taxiways and Aprons |
|
L |
<1/4 in.
|
<1/2 in. |
|
M |
¼ to ½ in. |
½ to 1 in. |
|
H |
>½ in. |
>1 in. |