L - Cracks have only light spalling (little or no FOD potential) or no spalling, and can be filled or non-filled. If non-filled, the cracks have a mean width of ¼ in. (6 mm) or less; filled cracks are of any width, but their filler material is in satisfactory condition.

M - One of the following conditions exists: cracks are moderately spalled (some FOD potential) and can be either filled or non-filled of any width; filled cracks are not spalled or are lightly spalled, but filler is in unsatisfactory condition; non-filled cracks are not spalled or are only lightly spalled, but the mean crack width is greater than ¼  in. (6 mm); or light random cracking exists near the crack or at the corners of intersecting cracks.

H - Cracks are severely spalled with pieces loose or missing causing definite FOD potential. Cracks can be either filled or non-filled of any width.