#### § 213.331 Track surface.

(a) For a single deviation in track surface, each track owner shall maintain the surface of its track within the limits prescribed in the following table:

| Track surface (inches) | Class of track | | | |
| --- | --- | --- | --- | --- |
| 6 | 7 | 8 | 9 |
| The deviation from uniform1 profile on either rail at the mid-ordinate of a 31-foot chord may not be more than | 1 | 1 | 3/4 | 1/2 |
| The deviation from uniform profile on either rail at the mid-ordinate of a 62-foot chord may not be more than | 1 | 1 | 1 | 3/4 |
| Except as provided in [paragraph (b)](/on/2024-09-24/title-49/section-213.331#p-213.331(b)) of this section, the deviation from uniform profile on either rail at the mid-ordinate of a 124-foot chord may not be more than | 13/4 | 11/2 | 11/4 | 1 |
| The deviation from zero crosslevel at any point on tangent track may not be more than2 | 1 | 1 | 1 | 1 |
| Reverse elevation on curves may not be more than | 1/2 | 1/2 | 1/2 | 1/2 |
| The difference in crosslevel between any two points less than 62 feet apart may not be more than3 | 11/2 | 11/2 | 11/4 | 1 |
| On curved track, the difference in crosslevel between any two points less than 10 feet apart (short warp) may not be more than | 11/4 | 11/8 | 1 | 3/4 |
| | | | | |
| --- | --- | --- | --- | --- |
| 1 Uniformity for profile is established by placing the midpoint of the specified chord at the point of maximum measurement. | | | | |
| 2 If physical conditions do not permit a spiral long enough to accommodate the minimum length of runoff, part of the runoff may be on tangent track. | | | | |
| 3 However, to control harmonics on jointed track with staggered joints, the crosslevel differences shall not exceed 1 inch in all of six consecutive pairs of joints, as created by seven low joints. Track with joints staggered less than 10 feet apart shall not be considered as having staggered joints. Joints within the seven low joints outside of the regular joint spacing shall not be considered as joints for purposes of this footnote. | | | | |

(b) For operations at a qualified cant deficiency, Eu, of more than 5 inches, a single deviation in track surface shall be within the limits prescribed in the following table:

| Track surface (inches) | Class of track | | | |
| --- | --- | --- | --- | --- |
| 6 | 7 | 8 | 9 |
| The difference in crosslevel between any two points less than 10 feet apart (short warp) may not be more than | 11/4 | 1 | 11 | 3/4 |
| The deviation from uniform profile on either rail at the mid-ordinate of a 124-foot chord may not be more than | 11/2 | 11/4 | 11/4 | 1 |
| | | | | |
| --- | --- | --- | --- | --- |
| 1 For curves with a qualified cant deficiency, Eu, of more than 7 inches, the difference in crosslevel between any two points less than 10 feet apart (short warp) may not be more than three-quarters of an inch. | | | | |

(c) For three or more non-overlapping deviations in track surface occurring within a distance equal to five times the specified chord length, each of which exceeds the limits in the following table, each track owner shall maintain the surface of the track within the limits prescribed for each deviation:

| Track surface (inches) | Class of track | | | |
| --- | --- | --- | --- | --- |
| 6 | 7 | 8 | 9 |
| The deviation from uniform profile on either rail at the mid-ordinate of a 31-foot chord may not be more than | 3/4 | 3/4 | 1/2 | 3/8 |
| The deviation from uniform profile on either rail at the mid-ordinate of a 62-foot chord may not be more than | 3/4 | 3/4 | 3/4 | 1/2 |
| The deviation from uniform profile on either rail at the mid-ordinate of a 124-foot chord may not be more than | 11/4 | 1 | 7/8 | 5/8 |

[[78 FR 16106](https://www.federalregister.gov/citation/78-FR-16106), Mar. 13, 2013]