Hi-rail rail flaw testing puts a contractor's ultrasonic test truck on your track, so the owner still has work to do. You arrange track authority under 49 CFR Part 214, confirm the truck's hi-rail gear was inspected within the last 14 months (214.523), plan suspect verification under 213.113(b), and collect a 213.241 record for every mile tested.
Buyers searching for hi-rail track inspection services are often after one of two different jobs: visual track inspection by a 213.7 qualified inspector under 49 CFR 213.233, or internal rail flaw testing under 213.237. This article covers the second, from the owner's side of the job: what to set up before the truck arrives, what happens on the day, and what paperwork should come back.
It assumes the deployment decision is made. If you are still choosing between a hi-rail truck, a push cart and hand testing, read hi-rail truck vs inspection cart first. For how a hi-rail inspector works and how the vehicle itself is built, see the hi-rail track inspector guide.
In this article
- What does an owner arrange for hi-rail rail flaw testing?
- Which Part 214 on-track safety rules apply to a hi-rail test crew?
- What Subpart D rules apply to the hi-rail vehicle itself?
- How should setting on and off be planned?
- What happens when the test finds a suspect?
- What sets daily output on a hi-rail test?
- What records must come back under 213.237 and 213.241?
- Which safety and qualification records should the owner request?
- What this checklist doesn't settle
- How EMA Industries applies this
- Frequently asked questions
What does an owner arrange for hi-rail rail flaw testing?
The owner supplies the track, the authority and the decisions; the contractor supplies the test equipment, the qualified operators and the record. Hiring the work out doesn't move compliance. Under 49 CFR 213.5 the track owner stays responsible, and 213.5(f) adds anyone who performs the work. The track inspection services article explains that split in detail.
Here is the whole job on one page. Each row is covered in its own section below.
| Item | Rule | Usually arranged by | What to ask for or confirm |
|---|---|---|---|
| Which track, and why it's due | 213.237(c) | Owner | Segment limits, class, annual MGT, last test date |
| On-track safety program the crew works under | 214.307, 214.315 | Owner (the railroad's program) | A copy of the program pages that apply, and who gives the job briefing |
| Track authority and working limits | 214.319, 214.321 | Owner or dispatcher | Form of authority, limits, window times, who is roadway worker in charge |
| Hi-rail gear inspection | 214.523(a)–(b) | Contractor (vehicle employer) | Date of the last tram, wheel wear and gage inspection |
| Set-on and set-off points | Railroad operating rules | Owner | A list of crossings or pads, by milepost |
| Operator qualification | 213.238 | Contractor | Training program and 213.238(e) records |
| A person who can decide on a defect | 213.113(a), 213.7 | Owner | Name and phone number of the 213.7 designated person for the day |
| Remedial capability | 213.113(c) | Owner | Who can apply a speed restriction, joint bars or a rail change |
| Test record | 213.241(c) | Contractor prepares, owner keeps | Report format, delivery date, electronic system |
| Untested track | 213.237(g)–(h) | Owner decides | A list of every length not validly searched |
Key takeaway: if a row has no name against it before the truck mobilizes, that is where the test day will stall.
Which Part 214 on-track safety rules apply to a hi-rail test crew?
Every member of a hi-rail test crew is a roadway worker, and no one may foul a track without on-track safety established under Part 214. The 214.7 definition of a roadway worker covers employees "of a railroad, or of a contractor to a railroad" whose duties include inspection of track. "Fouling a track" means being close enough to be struck, "or in any case" within 4 feet of the field side of the near running rail. A hi-rail on the rail is fouling the track from the moment it sets on.
The crew works under the railroad's on-track safety program, not one it brings along. Under 214.307 each railroad keeps its own program, available to FRA, and notifies FRA in writing before it takes effect. A contractor arriving on a short line follows that short line's rules for briefings, authority and protection.
The core requirements for a moving test:
| Part 214 rule | What it requires for a hi-rail test |
|---|---|
| 214.315 job briefing | Before fouling, each worker is briefed on the on-track safety method, limits and duties, and acknowledges it |
| 214.319 working limits | Only one roadway worker in charge (RWIC) controls the working limits on a segment |
| 214.321 exclusive track occupancy | Authority comes from the dispatcher or control operator; oral authority is written down and repeated back |
| 214.323 foul time | The RWIC "shall not permit the movement of trains or other on-track equipment into or within working limits protected by foul time" |
| 214.353 RWIC qualification | The RWIC is trained in the railroad's operating rules and the territory's physical characteristics |
Because 214.323(d) bars on-track equipment from moving under foul time, a hi-rail test that travels along the track is normally run under exclusive track occupancy: a track warrant, track bulletin or similar authority, depending on the railroad's operating rules. Confirm the form with the host railroad.
Who acts as RWIC is a contract question. Part 214 requires one qualified RWIC; it doesn't say whose employee that person must be. Some owners send a qualified employee or pilot with the truck, and some programs let a contractor's employee qualify on the territory. Write the answer into the work order.
Why individual train detection doesn't work for a hi-rail test (214.337)
Individual train detection is the lone-worker method of watching for trains and stepping clear, and 214.337 rules it out for a hi-rail test in several ways. It may be used only by a lone worker (214.337(c)(1)), and a two-person test crew working on a common task is a roadway work group, not a lone worker (214.7). It needs "no power-operated tools or roadway maintenance machines" in use within hearing (214.337(c)(5)). And paragraph (g) closes the question:
"Individual train detection shall not be used to provide on-track safety for a lone worker using a roadway maintenance machine, equipment, or material that cannot be readily removed by hand." — 49 CFR 214.337(g)
A hi-rail truck can't be lifted off the rail by hand. So a hi-rail test needs working limits, whatever the crew size.
Horn warnings and adjacent tracks (214.339 and 214.336)
Two more Subpart C rules matter on multiple-track territory. Under 214.339, each railroad must have written procedures for horn and bell warnings from trains approaching roadway workers "or roadway maintenance machines" on or about the track. Paragraph (b) adds that the audible warning "shall not substitute for on-track safety procedures". A horn is a backup, never the protection.
214.336 can require protection on an adjacent controlled track (track centers 19 feet or less apart) when a work group with someone on the ground works with on-track equipment. It contains an exception for "a hi-rail vehicle or other rail-bound vehicle … being used for inspection or minor correction purposes", provided it isn't coupled to railroad cars (214.336(e)(3)(i)). The exception drops away if another work group is close enough to impair the crew's ability to see or hear trains. The job briefing has to settle it each day.
Key takeaway: plan for exclusive track occupancy with one named RWIC; Part 214 leaves no shortcut for a moving test truck.
What Subpart D rules apply to the hi-rail vehicle itself?
Part 214 Subpart D sets minimum safety standards for "on-track roadway maintenance machines and hi-rail vehicles" (214.501), but only some of its sections reach a hi-rail. Under 214.7, a hi-rail vehicle is "a roadway maintenance machine that is manufactured to meet Federal Motor Vehicle Safety Standards and is equipped with retractable flanged wheels". An "on-track roadway maintenance machine" is a different category: "non-highway" and over 7,500 lb. A highway-legal hi-rail truck isn't one, so the cab, lighting and horn rules in 214.505 to 214.519, which name only on-track machines, don't apply to it.
The sections that do name hi-rail vehicles:
| Section | Requirement for a hi-rail vehicle |
|---|---|
| 214.503 | The operator may refuse to run a hi-rail he or she believes in good faith doesn't comply or is unsafe; the employer needs written procedures to resolve challenges, naming its designated official |
| 214.521 | A flagging kit on board where the railroad's rules require flagging and the truck isn't inside a work group (or leads or trails one) |
| 214.523(a)–(b) | Hi-rail gear inspected at least annually, no more than 14 months apart; tram, wheel wear and gage measured; record kept until the next inspection |
| 214.523(c) | A "new" hi-rail (ordered after Dec. 26, 2003 or completed after Sept. 27, 2004) has a change-of-direction or backup alarm at least 3 seconds long and a 360-degree beacon |
| 214.523(d) | The operator checks the vehicle at the start of each shift; a non-complying condition is tagged, dated and reported; alarms and beacons are fixed within 7 calendar days |
| 214.525 | A tow bar or coupling device if the truck tows anything, within its braking capability on the grade |
| 214.531 and 214.533 | Non-complying conditions fixed within 7 calendar days, or 7 days after a back-ordered part arrives; out of on-track service at 30 days |
The vehicle's operator also needs machine training. 214.341 bars anyone from operating a roadway maintenance machine without training under 214.355 and knowledge of that machine's safety instructions. The 214.355 training covers keeping people clear of the moving machine and stopping short of obstructions, with qualification "evidenced by demonstrated proficiency".
Worked example: is the truck's hi-rail gear inspection current?
A contractor's truck is booked for a test on March 10, 2027. Its last 214.523(a) hi-rail gear inspection is dated January 20, 2026.
| Check | Calculation | Result |
|---|---|---|
| 14-month limit | January 20, 2026 + 14 months | Due by March 20, 2027 |
| Test day | March 10, 2027 | 10 days inside the limit: compliant |
| Longer job | Test days running to March 25, 2027 | The last 5 days (March 21–25) fall outside the limit unless the gear is re-inspected first |
The "at least annually" wording and the 14-month cap work together: the inspection is meant to happen every year, and 14 months is the outer limit. If your test program spans several weeks, check the date against the last day of the job, not the first. Ask for the record itself; 214.523(b) lets it be kept on the vehicle.
Key takeaway: the hi-rail gear record is a one-line check that takes a minute before mobilization and can stop a test day if it is missed.
How should setting on and off be planned?
Part 214 doesn't prescribe how a hi-rail sets on or off; the railroad's operating rules do. FRA said so in its 2016 safety advisory on maintenance machines at grade crossings, noting that Subpart C "does not mention, nor is it generally intended to address" travel-mode moves over crossings (FRA Safety Advisory 2016-01, 81 FR 14516). That puts the planning on the owner.
What the owner can settle before the test day:
- A list of set-on and set-off points by milepost. Usually public or private grade crossings, or a hi-rail pad. Mark the ones that won't work: crossings with a steep approach, poor surface, or heavy road traffic.
- Authority before fouling. The authority has to be in effect before the truck fouls the track, and the truck has to be set off and clear before the authority is released.
- Spacing against the window. Set-on points far from the test limits cost travel time inside the window. If the nearest usable crossing is 6 miles outside the limits, that is 12 miles of on-track travel per day.
- Road traffic and shunting. FRA's advisory warns that roadway maintenance machines "do not always shunt or maintain shunt in track circuits", so crossing warnings may not activate for the truck. Expect the crew to protect road traffic at the crossing.
- The start-of-shift check. Under 214.523(d)(1) the operator checks the vehicle "prior to using the vehicle at the start of the operator's work shift". Build that time in before the authority starts.
The hi-rail track inspector article covers crossing procedure and track-circuit shunting in more depth. For a hi-rail rail flaw testing contract, the owner's job is to supply the list and the authority, and to say who protects the crossing.
Key takeaway: give the contractor a milepost list of usable set-on points; it decides how much of the window is spent testing.
What happens when the test finds a suspect?
On a stop-and-verify hi-rail test, the truck stops at each suspect indication and a qualified operator checks it by hand before testing resumes. FRA's 2014 rule describes this start/stop process as testing "at a slow speed (normally not exceeding 20 mph)" (79 FR 4234). A 1999 university study of test-car data put it plainly:
"[I]n practice the vehicle stops frequently to hand verify indications." — B. D. Jeffrey and M. L. Peterson (Colorado State University), Assessment of Rail Flaw Inspection Data, MPC 99-106, Aug. 1999
The sequence at a suspect, and who owns each step:
| Step | What happens | Who | Rule |
|---|---|---|---|
| 1. Stop | The truck stops past the indication and backs up to it | Crew, inside the working limits | 214.321(d) |
| 2. Verify | The operator hand-tests the spot with a contact probe and judges whether it is a defect | 213.238 qualified operator | 213.238(b)(3) |
| 3. Classify and size | Defect type and size are recorded against the 213.113(c) table | Qualified operator | 213.241(c)(3)–(4) |
| 4. Mark | The rail is marked on both sides of the web and base (or at the head where blocked) | Crew | 213.237(e) |
| 5. Decide | A 213.7 designated person decides whether the track may stay in use, and under what remedial action | Owner | 213.113(a) |
| 6. Act | Replace or repair the rail, or apply the lettered remedial action | Owner | 213.113(b)–(c) |
The clock matters. Under 213.113(b), once the owner learns of an indication it must verify it within 4 hours, or immediately if the suspected defect would call for remedial action A, A2 or B. On a stop-and-verify test the crew verifies on the spot, which meets that clock. Continuous testing works differently, with 84-hour and 36-hour windows under 213.240; see continuous vs stop-and-verify rail testing.
Steps 5 and 6 are the owner's. A 213.238 operator isn't a 213.7 designated person unless the owner has also designated him or her. So the owner needs someone reachable during the window who can decide, and a way to apply the result: a speed restriction issued through the dispatcher, a gang with joint bars, or a rail change.
Not every indication is a defect. Worn or shelled rail, lubrication and weld geometry all return echoes, and false calls in rail UT explains why. Where the operator can't get a valid search at all, because coupling was lost or the rail surface masked the signal, 213.237(g) says that length "may not be considered as internally inspected". The owner then has to retest it, hold trains to 25 mph, or replace the rail before the deadline (213.237(h)).
Key takeaway: the contractor finds and verifies; the owner decides and acts, and needs both people on the phone during the window.
What sets daily output on a hi-rail test?
Daily output is the testing time left in the window multiplied by the average speed achieved, and both depend on your track more than on the truck. No federal rule sets a test speed, and no current public source gives a hi-rail average. The public figures are dated or are estimates:
| Figure | What it is | Source |
|---|---|---|
| "Normally not exceeding 20 mph" | FRA's description of start/stop testing speed while moving | 2014 final rule, 79 FR 4234 |
| 6 to 8 mph average | Test cars with stop-and-verify, 1999 data | MPC 99-106 (dated) |
| About 23 miles a day | Implied by FRA's 2014 small-entity estimate (70 miles in 3 days with a rented detector car) | 79 FR 4234 regulatory analysis (an estimate, not a measurement) |
Vendor ratings of 30 to 45 mph describe what a system can do on clean rail without stopping. They aren't test speeds. Ask any contractor for its planned miles per window on track like yours, and for the assumptions behind it.
The factors that move the number:
| Factor | Why it changes output | What the owner can do |
|---|---|---|
| Window length | Fixed overhead (briefing, set-on, calibration, set-off) comes out of every window | Book longer windows rather than more short ones |
| Distance to set-on points | Travel inside the authority is time not testing | Supply nearer set-on points |
| Suspect rate | Each suspect is a stop, a back-up and a hand test | Share last year's suspect and defect counts |
| Rail surface | Shelling, corrugation, dirt and heavy lubrication cause lost coupling and retests | Report known problem areas; time lubricator maintenance |
| Turnouts and special trackwork | Often hand tested, location by location | Give a turnout count by milepost |
| Joints and field welds | More reflectors and more checks per mile | Give rail type (jointed or CWR) by segment |
| Trains to clear | Each clearing move stops the test | Schedule windows in low-traffic periods |
| Calibration checks | Start- and end-of-shift checks on reference rail, plus any the procedure requires | Ask how often the procedure requires them |
| Weather | Rain, frost and heat affect coupling and safety | Agree weather-out terms in the contract |
The planning formula is simple: miles per window = (window time − fixed overhead − verification time − hand-test time) × average moving test speed. Every term except the window length comes from the contractor's procedure and your track. The hi-rail truck vs inspection cart article works the arithmetic through for a full network.
Key takeaway: ask for planned miles per window with the assumptions written down, then compare quotes on the same assumptions.
What records must come back under 213.237 and 213.241?
For each internal rail inspection, 213.241(c) lists six items the record must specify, and the owner must keep it at least 2 years after the inspection and 1 year after initial remedial action. The contractor writes most of it. The owner keeps it, and the owner completes one item.
| 213.241(c) item | What the contractor should deliver | Owner's part |
|---|---|---|
| (1) Date of inspection | Each test day | Check against the 213.237 due date |
| (2) Track inspected, with beginning and end points | Track number and milepost limits for each run | Check against the segment designated under 213.237(b) |
| (3) Location and type of defects found under 213.113 | Milepost or other locator, rail (north/south or left/right), defect type | File against the remedial action |
| (4) Size of defects, if not removed before the next train | Percent of head area or length, as the 213.113(c) table uses | Use for the remedial action choice |
| (5) Initial remedial action and its date | What was applied at the time of the test, if the crew was there | Owner's decision; the record isn't complete until it's filled in |
| (6) Location of any track not tested under 213.237(g) | Every length without a valid search, by milepost | Retest, hold trains to 25 mph, or replace (213.237(h)) |
Source: 49 CFR 213.241 on eCFR.
Three more rules shape the deliverable:
- Electronic records (213.241(j)): the system must identify each author uniquely, must not let a completed record be changed, and must store amendments separately. Storage must start within 72 hours of completing the inspection, by the person who made it.
- Availability (213.241(h)–(i)): records stay available to the people who did the inspection, to later inspectors of the segment, and to FRA on request. They are kept, not sent to FRA.
- Service failure rate (213.241(e)): the owner keeps the records behind its service failure rate calculation for each segment that has a 213.237(a) target. A contractor's test report doesn't do that for you.
Beyond the rule, a useful hi-rail test report also carries the calibration record for each shift, the operator's name and qualification for each run, and a list of suspects that proved to be non-defects. Ask for those in the contract. The 49 CFR 213.237 article explains the intervals and the valid-search definition behind items (1), (2) and (6).
Worked example: how long must the record be kept?
A hi-rail test runs on March 10, 2027 and finds a detail fracture. The owner applies a speed restriction that day, and the rail is replaced on April 2, 2027.
| Test | Date | Retention runs to |
|---|---|---|
| 2 years after the inspection | March 10, 2027 + 2 years | March 10, 2029 |
| 1 year after initial remedial action | March 10, 2027 + 1 year | March 10, 2028 |
| Keep until | Both conditions must be met | March 10, 2029 |
The replacement date doesn't extend retention, because 213.241(d) counts from the initial remedial action (the speed restriction). It would control only if initial action came more than a year after the test. Where the record is electronic, storage had to start by March 13, 2027 (72 hours after the test ended).
Key takeaway: write item (5) and the untested-track list into the report format, so the record is complete when it lands.
Which safety and qualification records should the owner request?
Before the test, ask for the records that show the operators, the vehicle and the crew meet the rules that bind them. One of these is an owner gate, not a courtesy. Under 213.238(a):
"A track owner shall not utilize a provider of rail flaw detection that fails to comply with the requirements of this paragraph." — 49 CFR 213.238(a)
That paragraph requires a documented training program and a record of the equipment types each operator is qualified on. The full request list:
| Record | Rule | What it should show |
|---|---|---|
| Documented operator training program | 213.238(a) | The program exists and names equipment types |
| Operator qualification records | 213.238(e) | Name, equipment type, date of qualification, date of most recent reevaluation |
| Experience basis | 213.238(c) | At least 160 hours of supervised rail flaw detection experience and demonstrated proficiency on each equipment type |
| Roadway worker on-track safety training | 214.343(b), (d) | Training at least once every calendar year; name, type of qualification and most recent date |
| RWIC qualification (if the contractor provides the RWIC) | 214.353 | Qualified on your railroad's operating rules and territory |
| Machine operator qualification | 214.341(b), 214.355 | Trained on the machine and its safety instructions |
| Hi-rail gear inspection | 214.523(a)–(b) | Tram, wheel wear and gage measured within 14 months |
| Good-faith challenge procedure | 214.503(c) | Written procedure and the employer's designated official |
| Training program statement for railroad clients | 243.101(e) | That the contractor's program was FRA-approved, or a similar program is kept under another rule |
| Drug and alcohol program coverage | Part 219 | That the crew is covered as maintenance-of-way staff (check with your Part 219 program manager) |
Two cautions apply. First, SNT-TC-1A certification on its own doesn't answer 213.238: it is a recommended practice employers use to certify NDT staff, while 213.238 asks for a rail flaw detection training program and equipment-specific qualification. Second, a qualification record is only as good as its equipment entry. An operator qualified on a push cart isn't qualified on a hi-rail system unless the record says so (213.238(c), "for each type of equipment"). The professional rail inspection services buyer's guide covers how to compare contractors on these records.
Key takeaway: the 213.238 records are the one request where a missing answer means the owner can't use the provider.
What this checklist doesn't settle
This checklist covers federal minimums for a stop-and-verify hi-rail test on the general railroad system. Several things sit outside it.
- Operating rules differ. Track warrant, bulletin and set-on procedures come from the host railroad's rulebook (GCOR, NORAC or its own). No public full text of those rulebooks was checked here.
- Isolated rail transit isn't under Part 213 or 214. Rapid transit not connected to the general system falls under FTA's 49 CFR Part 671 and the state safety oversight agency, whose rules on protection and records differ.
- A hi-rail test doesn't cover all of the rail. FRA's 2014 rule says the beams "normally scan the entire rail head and web, as well as the portion of the base directly beneath the web". Most of the base, and much of a turnout's frog and switch points, need other methods. Field welds may need a separate hand test of the base.
- Continuous testing has its own rules. Owners who choose 213.240 continuous testing take on verification windows, data review staff and an annual report that this article doesn't cover.
- Contracting doesn't transfer compliance. Only a 213.5(c) assignment with notice to FRA moves Part 213 responsibility, and even then FRA may hold both parties. See contracting Part 213 inspections.
- Rule texts change. FRA's August 31, 2026 final rule (91 FR 55749, effective Sept. 30, 2026) amended several Part 214 sections, though not the hi-rail sections cited here. Check eCFR for the current text before you write a contract.
This article isn't legal advice. Where a reading of Part 214 decides whether a crew is protected, ask the host railroad's on-track safety officer.
How EMA Industries applies this
EMA Industries provides ultrasonic rail flaw testing for transit agencies, short lines and industrial track owners, along with rail weld inspection and NDT Level III support. EMA is based in Southern California and mobilizes nationwide. Level III support can include reviewing a provider's rail flaw procedure, 213.238 qualification records and 213.241 report format against the lists above before a test is booked.
To scope ultrasonic rail flaw testing or a Level III review for your track, see ultrasonic rail flaw testing or contact EMA Industries.
Frequently asked questions
Who provides the roadway worker in charge for a contractor's hi-rail test?
Part 214 requires one qualified RWIC to control the working limits (214.319), but it doesn't say whose employee that must be. The RWIC must be qualified under 214.353 on the railroad's operating rules and the territory. Many owners send their own qualified employee or pilot; some programs qualify a contractor's employee. Put the answer in the work order.
How often must a hi-rail test truck's gear be inspected?
Under 214.523(a), the hi-rail gear must be inspected at least once a year, with no more than 14 months between inspections. Tram, wheel wear and gage are measured and adjusted. The employer keeps the record until the next inspection, on the vehicle or at a designated location. Separately, the operator checks the vehicle at the start of every shift (214.523(d)).
Can a hi-rail rail flaw test run under foul time?
Not as a moving test. 214.323(d) says the RWIC "shall not permit the movement of trains or other on-track equipment into or within working limits protected by foul time". A test truck moves along the track, so it normally runs under exclusive track occupancy (214.321). Check the form of authority with the host railroad.
How long must hi-rail rail test records be kept?
Under 213.241(d), at least two years after the inspection and one year after initial remedial action, so the later date controls. Records of continuous tests under 213.240 follow the same "whichever is later" rule in 213.241(f)(5). Electronic records must be stored within 72 hours of the inspection (213.241(j)(5)).
What happens to track the hi-rail couldn't test properly?
If the qualified operator decides a valid search couldn't be made over a length of track, that length doesn't count as inspected (213.237(g)). It goes on the record under 213.241(c)(6). Before the test deadline, the owner must retest it, cut speed to 25 mph until it is tested, or replace the rail (213.237(h)).
Sources
- 49 CFR 214.7 Definitions (eCFR); text read on Cornell LII, Oct. 2026
- 49 CFR 214.307, 214.315, 214.319, 214.321, 214.323 (eCFR, Part 214 Subpart C)
- 49 CFR 214.336 Adjacent tracks (eCFR)
- 49 CFR 214.337 Lone workers (eCFR)
- 49 CFR 214.339 Audible warning from trains (eCFR)
- 49 CFR 214.341, 214.343, 214.353, 214.355 (eCFR)
- 49 CFR 214.501–214.533, Subpart D (eCFR), including 214.503 and 214.523
- 49 CFR 213.113 Defective rails (eCFR)
- 49 CFR 213.237 Inspection of rail (eCFR)
- 49 CFR 213.238 Qualified operator (eCFR)
- 49 CFR 213.241 Inspection records (eCFR)
- FRA, Track Safety Standards; Improving Rail Integrity, final rule, 79 FR 4234 (Jan. 24, 2014)
- FRA Safety Advisory 2016-01, Movement of Roadway Maintenance Machines Over Highway-Rail Grade Crossings, 81 FR 14516 (Mar. 17, 2016)
- FRA, Repealing Outdated Railroad Workplace Safety Requirements and Making Other Improvements, final rule, 91 FR 55749 (Aug. 31, 2026)
- Jeffrey, B. D. and Peterson, M. L., Assessment of Rail Flaw Inspection Data, MPC 99-106, Mountain-Plains Consortium, Aug. 1999