---
kind: "section"
citation: "49 C.F.R. § 232.305"
title: "49"
number: "232.305"
heading: "Single car air brake tests."
url: "https://uscodex.org/cfr/49/232.305"
---

# §232.305. Single car air brake tests.

- (a) Single car air brake tests must be performed by a qualified person in accordance with either [Section 3.0](/cfr/49/3.0.md), “Tests-Standard Freight Brake Equipment,” and [Section 4.0](/cfr/49/4.0.md), “Special Tests,” AAR Standard S-486-18; [Section 3.0](/cfr/49/3.0.md), “Single-Car Test Requirements,” [Section 4.0](/cfr/49/4.0.md), “Special Tests,” and [Section 13.0](/cfr/49/13.0.md) “4-Pressure Single-Car Test Requirements,” AAR Standard S-4027-18; an alternative procedure approved by FRA pursuant to [§ 232.17](/cfr/49/232.17.md); or a modified procedure approved in accordance with the provisions contained in [§ 232.307](/cfr/49/232.307.md).
- (b) Except as provided in [§ 232.303(e)](/cfr/49/232.303.md?p=e), a railroad shall perform a single car air brake test on a car when:
  - (1) A car has its brakes cut-out or inoperative when removed from a train or when placed on a shop or repair track, as defined in [§ 232.303(a)](/cfr/49/232.303.md?p=a);
  - (2) A car is on a shop or repair track, as defined in [§ 232.303(a)](/cfr/49/232.303.md?p=a), for any reason and has not received either:
    - (i) A manual single car air brake test (AAR Standard S-486) within the previous 12-month period;
    - (ii) An automated single car air brake test (AAR Standard S-4027 §§ [3.0](/cfr/49/3.0.md) and [4.0](/cfr/49/4.0.md)) within the previous 24-month period;
    - (iii) Or a 4-pressure single car air brake test (AAR Standard S-4027 [§ 13.0](/cfr/49/13.0.md)) within the previous 48-month period;
  - (3) A car is found with missing or incomplete single car air brake test information;
  - (4) **One or more of the following conventional air brake equipment items is removed, repaired, or replaced—**
    - (i) Brake reservoir;
    - (ii) Control valve mounting gasket;
    - (iii) Pipe bracket stud;
    - (iv) Service portion;
    - (v) Emergency portion; or
    - (vi) **Pipe bracket.**
  - (5) **A car is found with one or more of the following wheel defects—**
    - (i) Built-up tread, unless known to be caused by hand brake left applied;
    - (ii) Slid flat wheel, unless known to be caused by hand brake left applied; or
    - (iii) **Thermal cracks.**
- (c) Except as provided in [paragraph (d)](#d) of this section, each car shall receive a single car air brake test no less than every 5 years.
- (d) Each car shall receive a single car air brake test no less than 8 years from the date the car was built or rebuilt.
- (e) A single car air brake test shall be performed on each new or rebuilt car prior to placing or using the car in revenue service.
- (f) The Director of the Federal Register approves the incorporation by reference of the standards required in this section into this section in accordance with 5 U.S.C. [552(a)](/usc/5/552.md?p=a) and [1](/usc/5/1.md) CFR [part 51](/cfr/49/part51.md). You may inspect a copy of the material at the Federal Railroad Administration, Docket Clerk, 1200 New Jersey Avenue SE, Washington, DC 20590 (telephone: 855-368-4200). You may also inspect the material at the National Archives and Records Administration (NARA). For information on the availability of this material at NARA, email fedreg.legal@nara.gov, or go to: www.archives.gov/federal-register/cfr/ibr-locations.html. You may obtain the material from the following source(s):
  - (1) **Association of American Railroads (AAR), 425 Third Street SW, Washington, DC 20024, telephone—**
  - (202) 639-2345, email: publications@aar.com, website: https://aarpublications.com.
    - (i) **AAR Standard S-486, “Code of Air Brake System Tests for Freight Equipment—** Single Car Test,” Revised 2018 (contained in AAR Manual of Standards and Recommended Practices, Brakes and Brake Equipment), also referred to as AAR Standard S-486-18.
    - (ii) **AAR Standard S-4027, “Automated Single-Car Test Equipment, Conventional Brake Equipment—** Design and Performance Requirements,” Revised 2018 (contained in AAR Manual of Standards and Recommended Practices, Brakes and Brake Equipment), also referred to as AAR Standard S-4027-18.
  - (2) [Reserved]

## Notes

### Amendments

[66 FR 39688, Aug. 1, 2001, as amended at 73 FR 61553, Oct. 16, 2008; 74 FR 25174, May 27, 2009; 85 FR 80573, Dec. 11, 2020]

### Authority

Authority: 49 U.S.C. 20102-20103, 20107, 20133, 20141, 20301-20303, 20306, 21301-20302, 21304; 28 U.S.C. 2461 note; and 49 CFR 1.89.

### Source

Source: 66 FR 4193, Jan. 17, 2001, unless otherwise noted.

### Amendments

[66 FR 39688, Aug. 1, 2001, as amended at 73 FR 61553, Oct. 16, 2008; 74 FR 25174, May 27, 2009; 85 FR 80573, Dec. 11, 2020]