Rail Inspection RFP by Track Class: FRA Scope Guide

A rail inspection RFP by track class starts from 49 CFR 213.237(c): Class 4 and 5 track, and Class 3 track with regularly scheduled passenger trains or a hazmat route, must be internally tested every 370 days or 30 million gross tons (MGT), whichever is shorter. Other Class 3 track has a looser rule, and Class 1–2 track has none.

That one rule decides most of what a testing contract has to buy. This guide maps each FRA track class to the inspection scope an RFP should specify, then works through one RFP for a network that mixes Class 2, 3 and 4 track. For the general explanation of Part 213 and its track classes, see our FRA Track Safety Standards guide. This page covers only how class changes what you put out to bid.

Why does track class decide the scope of a rail inspection RFP?

Track class sets the maximum speed a segment may carry, and almost every inspection interval in Part 213 is keyed to it. Change the class and you change how often rail must be tested, how often track must be walked or ridden, and which subpart of the rule applies.

Under 49 CFR 213.9, each segment has an "intended class" chosen by the track owner. FRA doesn't assign classes. If a segment doesn't meet every requirement of its intended class, 213.9(b) reclassifies it "to the next lowest class of track for which it does meet all of the requirements". Owners usually record the class of each segment in the timetable or in special instructions.

For an RFP writer this means three things:

Class is per segment, not per railroad. One short line or transit system can hold excepted track, Class 2 yard leads and Class 4 main line, each with a different test obligation.
Traffic matters as much as class on Class 3 track. Passenger service and hazardous materials tonnage move a Class 3 segment onto the stricter schedule.
The class is the owner's decision, and the RFP should state it. A bidder can't price an interval it has to guess.

Key takeaway: the segment list with class and traffic is the core of the scope, and every other clause depends on it.

Class 1 track is not a Class I railroad

"Class 1 track" is the lowest numbered FRA track class, limited to 10 mph for freight. A "Class I railroad" is a large carrier classified by annual operating revenue under Surface Transportation Board rules. The two have nothing to do with each other. A Class I railroad runs plenty of Class 1 yard track, and a small short line can maintain Class 4 main line. An RFP should always say "track class" to avoid the confusion.

What does each FRA track class require?

FRA defines nine track classes plus excepted track. Classes 1 to 5 are in Subparts A to F of Part 213, and Classes 6 to 9 are in Subpart G. The two tables below give the speed, the visual inspection frequency, the internal rail test interval and the geometry measurement trigger for each class, taken from the rule text.

Maximum speeds and who inspects

Class	Freight max (mph)	Passenger max (mph)	Inspections made by
Excepted	10	No occupied passenger trains	Person designated under 213.7
1	10	15	Person designated under 213.7
2	25	30	Person designated under 213.7
3	40	60	Person designated under 213.7
4	60	80	Person designated under 213.7
5	80	90	Person designated under 213.7
6	110 (all trains)	110	Person designated under 213.305
7	125 (all trains)	125	Person designated under 213.305
8	160 (all trains), with FRA approval	160	Person designated under 213.305
9	220 (all trains), with FRA approval	220	Person designated under 213.305

Sources: 213.9, 213.4 and 213.307 on eCFR.

Section 213.307 sets one speed for all trains on Class 6 and higher track. Freight may run at those speeds only if its vehicles are qualified under 213.329 and 213.345 and the loading and hazmat conditions in the footnote are met. Speeds above 125 mph are authorized "only in conjunction with FRA regulatory approval addressing other safety issues presented by the railroad system."

Inspection intervals by class

Class	Visual track inspection	Internal rail inspection	Track geometry measurement system (TGMS)
Excepted	Class 1 frequency (213.4(c))	None required	Not required
1–3, main track and sidings	Weekly, at least 3 calendar days apart; twice weekly (at least 1 day apart) if the track carries passenger trains or carried more than 10 MGT the previous year	Class 1–2: none. Class 3: see the next section	Only for operation at a qualified cant deficiency over 5 in.: twice per calendar year, at least 120 days apart
1–3, other track	Monthly, at least 20 calendar days apart	Same as above	Same as above
4 and 5	Twice weekly, at least 1 calendar day apart	370 days or 30 MGT, whichever is shorter	Same as above
6	Twice weekly, at least 2 calendar days apart	Twice a year, at least 120 days apart (213.339)	Once per calendar year, at least 170 days apart (twice, 120 days apart, above 5 in. cant deficiency)
7	Twice weekly, at least 2 calendar days apart	Twice a year, at least 120 days apart	Twice in any 120 days, at least 25 days apart
8	Twice weekly, at least 2 calendar days apart	Twice a year, at least 120 days apart	Twice in any 60 days, at least 12 days apart
9	Three times per week	Twice a year, at least 120 days apart	Twice in any 60 days, at least 12 days apart

Sources: 213.233(c), 213.237(c), 213.333(a), 213.339(a) and 213.365(c). The inspection week runs Sunday to Saturday. A footnote to 213.233 relaxes the twice-weekly passenger rule for some weekend-only tourist and excursion service.

Two other class-keyed rules often end up in the same contract. Switches, turnouts and track crossings are inspected on foot at least monthly on every class (213.235), and CWR joint inspections per year depend on class, traffic type and tonnage under the CWR plan rule in 213.119(h)(6).

Class	CWR joint inspections a year, freight (<40 / 40–60 / >60 MGT)	Passenger (<20 / ≥20 MGT)
5 and above	2 / 3 / 4	3 / 3
4	2 / 3 / 4	2 / 3
3	1 / 2 / 2	2 / 2
2	0 / 0 / 0	1 / 1
1 and excepted	0	0 (excepted: n/a)

Key takeaway: visual inspection and internal rail testing are separate obligations with separate rules, and a bid package should never merge them into one "inspection frequency".

Which track classes need internal rail testing under 213.237?

Internal rail testing is required on Class 3, 4 and 5 track only, at two different intervals. The text of 49 CFR 213.237(c) reads:

"Internal rail inspections on Class 4 and 5 track, or Class 3 track with regularly-scheduled passenger trains or that is a hazardous materials route, shall not exceed a time interval of 370 days between inspections or a tonnage interval of 30 million gross tons (mgt) between inspections, whichever is shorter."

The same paragraph then sets the rule for all other Class 3 track: at least once each calendar year, with no more than 18 months between inspections, or at least once every 30 MGT, "whichever interval is longer, but in no case may inspections be more than 5 years apart."

Segment type	Interval	Which limit usually controls
Class 4 or 5	370 days or 30 MGT, whichever is shorter	Tonnage on lines above about 29.6 MGT a year; calendar below that
Class 3 with regularly scheduled passenger trains	370 days or 30 MGT, whichever is shorter	Calendar on most commuter and regional lines
Class 3 hazardous materials route	370 days or 30 MGT, whichever is shorter	Depends on tonnage
Other Class 3	Calendar year (18 months max) or 30 MGT, whichever is longer, never more than 5 years	The calendar year on busy lines; tonnage up to the 5-year cap on light lines
Class 1, Class 2 and excepted	No 213.237 interval	Owner policy
Class 6 to 9	Twice a year, at least 120 days apart (213.339)	Calendar only

A hazardous materials route under 213.237(j)(1) is track that carries at least 10,000 car loads or intermodal portable tank car loads of hazardous materials in a calendar year, or at least 4,000 loads of the materials listed in 49 CFR 172.820. The bidder can't work this out from the track chart, so the RFP should say which segments qualify.

Is ultrasonic testing required only from Class 5 up?

No. A common claim is that ultrasonic testing becomes required "at Class 5 and above", and it's wrong in two ways. The requirement starts at Class 3 under the conditions above, and Part 213 never says "ultrasonic". The rule requires "internal rail inspections" with equipment that can detect defects between joint bars (213.237(f)). Ultrasonic testing is how the industry meets it, but the method is the owner's and contractor's choice.

The rule also counts only a valid search, which 213.237(j)(4) defines as "a continuous inspection for internal rail defects where the equipment performs as intended and equipment responses are interpreted by a qualified operator as defined in § 213.238." Rail that couldn't be searched must be re-searched, run at no more than 25 mph, or replaced before the deadline (213.237(h)). The full rule is explained in our 49 CFR 213.237 guide, and the calendar-vs-tonnage arithmetic in How often must rail be tested?.

Class 3 and below: the parts buyers overlook

Plug rail is a common gap. Under 213.237(c)(1) to (3), any replacement rail laid in track that must be tested has to have been tested for internal flaws. Plug rail installed after March 25, 2014 can't exceed 30 MGT in its old and new locations combined since its last test. Otherwise trains over it are held to Class 2 speed until it is tested. If the contractor is also testing stored rail, write that into the scope as its own line item.

Key takeaway: price Class 3 segments by their traffic, not by their class number alone, and list Class 1 and 2 testing as optional work the owner has chosen to add.

How does excepted track change the RFP?

Excepted track carries no internal rail test requirement and is visually inspected at the Class 1 frequency, but it comes with operating limits the bidder should know. 49 CFR 213.4 lets an owner designate a segment as excepted track if:

it is identified in the timetable, special instructions, general order or other records available for inspection
it isn't within 30 ft of an adjacent track that can be used at more than 10 mph at the same time
it is inspected under 213.233(c) and 213.235 at the Class 1 frequency
it isn't on a bridge (including 100 ft of approach on either side) or on a public street or highway, if cars with placarded hazardous materials move over it

Operations are limited to 10 mph, with no occupied passenger trains and no more than five placarded hazmat cars in a freight train. Gage may not exceed 4 ft 10¼ in. The owner must give FRA's Track and Structures Division at least 10 days' notice before taking a segment out of excepted status.

For an RFP, list excepted segments separately. A contractor testing them is doing elective work, so the owner decides the frequency. If the owner plans to return a segment to Class 1 or higher, note it in the scope: from that date the segment's normal class rules apply.

Does track class decide when a geometry car is required?

Only on Class 6 and higher track, or where trains run at more than 5 inches of qualified cant deficiency. That is the trigger in 49 CFR 213.333(a). On Class 1 to 5 track, a track geometry measurement system is required "for operations at a qualified cant deficiency, Eu, of more than 5 inches", at least twice per calendar year with at least 120 days between runs. Without that high-cant-deficiency operation, Part 213 sets no geometry car requirement for Class 4 or Class 5 track.

Some guides say Class 4 and above "require geometry measurement cars" or that Class 5 track needs geometry measurement technology by law. Neither is in the rule. Many railroads run geometry cars on Class 4 and 5 main line as policy, but that is an owner choice, and an RFP shouldn't present it as a federal requirement.

Two other rules are worth knowing:

Automated inspection on concrete ties (213.234). Class 4 and 5 main track with concrete crossties, and Class 3 concrete-tie main track with regularly scheduled passenger trains, must get automated inspection as a supplement to visual inspection when the owner is a Class I or II railroad, an intercity passenger railroad, a commuter railroad or a small governmental jurisdiction serving more than 50,000 people. The inspection targets the 213.109(d)(4) crosstie conditions. 213.234 sets the frequency by tonnage.
A proposed geometry rule. An October 2024 FRA proposal would add a track geometry measurement requirement (213.236) for busier Class 1 to 5 track. We found no final rule as of October 2026. Check its status before you write it into a contract.

Key takeaway: if your RFP bundles geometry measurement with rail testing on Class 1 to 5 track, say whether it is a regulatory run under 213.333 or an owner-policy run.

Who performs the inspections the RFP is buying?

The track owner's own qualified persons, or contractors working for the owner. FRA doesn't perform them. 49 CFR 213.7(b) puts the duty on the owner:

"Each track owner to which this part applies shall designate qualified persons to inspect track for defects."

A designated inspector needs at least a year of track inspection experience, or a combination of experience and training, and must show the owner they understand the Part 213 requirements for the track they cover. On Class 6 and higher track the designation comes under 213.305 instead. FRA's own inspectors, and state inspectors under 49 CFR Part 212, audit compliance. They don't carry out the owner's required inspections.

Internal rail testing has a separate qualification rule. Under 213.238, each provider of rail flaw detection needs a documented training program, and each operator needs written authorization and at least 160 hours of supervised experience on the equipment type. The track owner "shall not utilize a provider of rail flaw detection that fails to comply". Section 213.5(f) adds that a contractor performing any function the part requires must perform it "in accordance with this part."

Class 1 and 2 inspections aren't made "by qualified FRA inspectors on foot", as is sometimes written. The inspections are the railroad's, made by its designated persons. Walking is only one option: 213.233(b) allows inspection on foot or from a vehicle, at no more than 5 mph over crossings and turnouts.

How should a rail inspection RFP by track class be structured?

Give bidders a segment table first, then tie every scope item to a rule and a class. A typical structure:

Segment schedule. For each segment: milepost limits, track number, track miles, track class, annual MGT, passenger service yes or no, hazmat route yes or no, rail type and weight, and tie type.
Last test date and tonnage since. Without these the contractor can't schedule within the 370-day or 30 MGT limit, especially in the first contract year.
Interval basis per segment. State which 213.237(c) rule applies. On "other Class 3" segments, say whether you want the legal minimum or a shorter owner interval.
Test method and process. Stop-and-verify or continuous testing under 213.240. Continuous testing changes verification timing, so the choice affects the owner's staffing.
Operator qualification. Ask for the provider's 213.238 training program and each operator's qualification record.
Notification and remedial action roles (next section).
Records. Name the 213.241 fields the contractor delivers and the format. The record of "initial remedial action taken and the date thereof" can only be finished by the owner.
Optional items. Class 1 and 2 testing, excepted track, stored plug rail, joint bar inspection, and CWR joint inspections under 213.119(h)(6).
Track access. Work windows, roadway worker protection under Part 214, and who provides the employee in charge.

Our rail inspection RFP guide covers proposal evaluation and contractor selection. The RFP manual for ultrasonic testing covers technical UT requirements. Public agencies should also read Rail Inspection Services for Government and Transit Authorities for jurisdiction and procurement rules.

What should the RFP say about 213.113 remedial actions?

The RFP should say who verifies an indication, how fast the contractor reports it, and who applies the remedial action from the 49 CFR 213.113 table. Finding a defect is the contractor's job. Deciding what happens to the track is the owner's.

Section 213.113(a) says a person designated under 213.7 "shall determine whether the track may continue in use." Under 213.113(b), the owner must verify an indication within four hours, or immediately where it points to a defect requiring remedial action A, A2 or B. That clock runs from when the owner learns of the indication, so the contract's notification path sets how much of the four hours is left.

Track class changes what each remedial action means in practice, because most speed actions read "or the maximum allowable speed under § 213.9 for the class of track concerned, whichever is lower":

Remedial action (213.113 notes)	Speed effect on Class 2 (25 mph freight)	Speed effect on Class 4 (60 mph freight)
B: limit set by a designated person, no more than 30 mph	25 mph class limit already lower; a designated person with at least 1 year of supervisory experience still sets the limit	Cut to 30 mph or less
C: joint bars within 10 days	No immediate speed change in the note for Class 2	30 mph on Class 3–5 until bars are applied, then 50 mph (a 213.237-found defect may run at 50 mph for up to 4 days)
H: limit to 50 mph	No change	Cut to 50 mph
I: limit to 30 mph	No change	Cut to 30 mph
A: a designated person visually supervises each operation	Applies on every class	Applies on every class

These speed values come from the remedial action notes in the 2014 rule text; the table itself appears only as an image in the eCFR. Each defect type and size has its own row, so see our guide to FRA defect codes and 213.113 for the defect-by-defect actions.

Write these points into the RFP:

the reporting time for each class of finding: immediate for suspected A, A2 and B defects, and a set number of hours for the rest
how defects are marked on track under 213.237(e) (both sides of the web and base, or on or next to the head where those are inaccessible)
the owner's 213.7 contact who receives findings and decides on remedial action
whether the contractor may protect the location (a crew member watching moves) until the owner's person arrives

Worked example: one RFP for a mixed Class 2, 3 and 4 network

One owner, five segments, three classes: each segment's interval comes from its own rule. The figures are illustrative. Assume single track throughout, so route miles equal track miles.

Segment	Class	Track miles	Traffic	Rule that applies	Maximum test interval
A: freight main line	4	22	45 MGT a year	213.237(c), shorter of 370 days / 30 MGT	30 ÷ 45 × 365 = 243 days (tonnage controls)
B: shared commuter branch	3	9	8 MGT, regularly scheduled passenger trains	213.237(c), shorter of 370 days / 30 MGT	30 MGT takes 3.75 years, so 370 days controls
C: light freight branch	3	14	4 MGT, no passenger trains, not a hazmat route	213.237(c), longer of calendar year / 30 MGT, 5-year cap	30 MGT takes 7.5 years, so the 5-year cap controls
D: busy freight connector	3	6	40 MGT, no passenger trains, not a hazmat route	213.237(c), longer of calendar year / 30 MGT	30 MGT comes after 274 days, but the longer limit applies: once each calendar year, no more than 18 months apart
E: industrial lead (main track)	2	5	1 MGT	No 213.237 interval	Owner policy only

The visual inspection rules for the same segments come from 213.233(c):

Segment	Visual inspection under 213.233(c)	Why
A	Twice weekly, at least 1 calendar day apart	Class 4
B	Twice weekly, at least 1 calendar day apart	Class 3 carrying passenger trains
C	Weekly, at least 3 calendar days apart	Class 3 main track, 4 MGT, no passengers
D	Twice weekly, at least 1 calendar day apart	Class 3 with more than 10 MGT the previous year
E	Weekly, at least 3 calendar days apart	Class 2 main track, 1 MGT

Turning the intervals into a bid quantity

Average track miles of internal testing needed a year, if every test is made exactly at the limit:

A: 365 ÷ 243.3 = 1.5 tests a year × 22 miles = 33.0 track miles. That is two tests in some years and one in others.
B: 1 test a year × 9 miles = 9.0 track miles.
C: 1 test every 5 years × 14 miles = 2.8 track miles a year on average.
D: 1 test a year × 6 miles = 6.0 track miles.
E: 0 required.

That is 33.0 + 9.0 + 2.8 + 6.0 = 50.8 track miles a year of required testing on average.

In practice no owner schedules at the exact limit. A bad search near the deadline leaves no time to re-test. Segment A is the one to watch: at 45 MGT a year, a test planned at 243 days has no margin if tonnage runs ahead of forecast. The RFP should ask for a test about every 7 months (around 213 days, roughly 26 MGT) and price that as 2 passes in each contract year, or 44 track miles a year on that segment.

The Class 3 segments show why "Class 3" alone isn't enough for a bidder. Segment D carries five times segment B's tonnage, yet B must be tested within 370 days and D only once each calendar year, because B carries passengers. Segment C could legally go 5 years between tests. An owner with old rail or a history of broken rail there will want a shorter interval, and the RFP is where to say so.

Segment E carries no federal test obligation. If the owner wants it tested, list it as an optional line item with its own frequency so it isn't mistaken for a compliance requirement.

The RFP's segment schedule for this network would therefore state: class, track miles, MGT, passenger and hazmat status, last test date and MGT since that test, the interval rule, and the owner's chosen interval if shorter.

What happens to the RFP when a segment changes class?

A class change during the contract changes the test interval from that date, so the RFP should say how reclassification is handled. The common cases:

Upgrading Class 3 to Class 4, for example after tie and surfacing work, moves an "other Class 3" segment from the calendar-year rule to the 370-day / 30 MGT rule. The next test may fall due much sooner than the contract schedule assumed.
Starting passenger service on Class 3 track has the same effect, and it also brings twice-weekly visual inspection under 213.233(c).
Downgrading under 213.9(b) happens when track no longer meets its intended class. A Class 4 segment that drops to Class 3 may move to a looser interval, but only if it carries no passenger trains and isn't a hazmat route.
Missing the service failure target. If a segment misses its 213.237(a) failure rate for two consecutive years, 213.237(d) requires the owner, for the area with the most service failures, either to cut the test tonnage interval to 10 MGT or to reduce the track to Class 2 until the target is met. A 10 MGT interval can triple the passes on a busy segment.

A practical clause: the owner notifies the contractor in writing of any change in class, passenger status or hazmat status, and the contract's unit rate per track mile applies to the revised number of passes.

What doesn't track class tell an RFP writer?

Track class sets federal minimums for the track. It says nothing about the rail's condition, the right test method or whether Part 213 applies at all. Its limits:

Part 213 doesn't apply to every rail system. Under 213.3(b)(3) it excludes track "used exclusively for rapid transit operations in an urban area that are not connected to the general railroad system". Isolated transit systems fall under FTA rules and their state safety oversight agency. In California, CPUC General Order 143-B uses the 213.9 classes and Part 213 track standards as a guideline, but not the inspection subpart. A transit RFP may borrow class-based intervals as policy, but it should say that it is doing so.
The rule is a minimum. Section 213.1(a) lets owners adopt more stringent requirements. Many owners test Class 4 track more often than 370 days, and many test Class 2 track that the rule doesn't reach.
Class doesn't describe rail condition. Two Class 3 segments can need very different attention depending on rail age, weight, defect history and surface condition. Heavy shelling can block a valid search, and class can't predict that.
Part 213 names no test method. It requires internal rail inspections and a valid search, but sets no probe angles, sensitivity or test speed. Those belong in the technical section of the RFP.
CWR isn't a class requirement. Part 213 doesn't make continuous welded rail mandatory at Class 7 or any other class. Subpart G still has rail joint requirements for Class 6 and higher (213.351) and a surface footnote for jointed track (213.331). CWR plans under 213.118 and 213.119 apply to any owner with CWR, whatever the class.
Speeds in the table are limits, not service speeds. Amtrak's NextGen Acela trains, which entered service in August 2025, are designed for up to 160 mph, 10 mph faster than the first-generation fleet's 150 mph. Press reports describe 160 mph running only on short upgraded stretches in New Jersey. Check current Amtrak information before quoting a figure.

How EMA Industries applies this

EMA Industries performs ultrasonic rail flaw testing for transit agencies, short lines and industrial track owners. We are based in Southern California and mobilize nationwide. When an owner sends us a segment list with class, tonnage and passenger and hazmat status, we work out the 213.237 interval for each segment and point out where an owner interval should be shorter. We can also scope rail weld inspection and Level III support in the same package. Contact us with your segment schedule for a test plan and quote.

FRA Track Safety Standards (49 CFR Part 213), the general guide to the rule and its classes
49 CFR 213.237 rail flaw detection requirements
How often must rail be tested?
FRA defect codes and 213.113 remedial actions
Rail inspection RFP guide
RFP manual for ultrasonic testing
Rail inspection services for government and transit authorities

FAQ

How often does Class 3 track need internal rail testing?

It depends on traffic. Class 3 track with regularly scheduled passenger trains, or on a hazardous materials route, must be tested at least every 370 days or 30 MGT, whichever is shorter. Other Class 3 track must be tested once each calendar year (no more than 18 months apart) or every 30 MGT, whichever is longer, and never more than 5 years apart (49 CFR 213.237(c)).

Does Class 1 or Class 2 track have to be ultrasonically tested?

Part 213 sets no internal rail test interval for Class 1 or Class 2 track, or for excepted track. Owners still test it by policy, often on older rail or where hazardous materials move. An RFP should list that testing as optional work at the owner's chosen frequency.

What is the internal rail test interval for Class 6 and higher track?

Section 213.339(a) requires a continuous search of all rail at least twice a year, with at least 120 days between inspections, on Class 6 to 9 track. There is no tonnage element, and the remedial actions are in 213.337 rather than 213.113.

Who decides a segment's track class?

The track owner. Section 213.9 speaks of a segment's "intended class" and drops it to the next lower class it meets if it falls short. FRA doesn't assign classes, but FRA and state inspectors check that track meets the class the owner operates it at.

Can one RFP cover track of several classes?

Yes, and most do. Give each segment its own row with class, track miles, tonnage, passenger and hazmat status and last test date, then state the interval rule per segment. The worked example above shows a Class 2, 3 and 4 network priced as one contract.