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U.S. Department of Transportation U.S. Department of Transportation Icon United States Department of Transportation United States Department of Transportation
FHWA Highway Safety Programs


Note: This document summarizes current practices but does not set standards; practitioners are advised to check current local standards and requirements (refer to Disclaimer and Quality Assurance Statement). Users of the data provided within this document should anticipate possible variations from current information within this document should anticipate possible variations from current information within the FRA databases, which are updated monthly.

Several issues are important to highway-rail crossing safety and operations that either were not specifically covered in previous chapters or warrant special consideration. These include the following:

  • Private Crossings
  • Short-line Railroads
  • LRT and Busways
  • High-Speed Rail
  • Trucks and Buses
  • Bicycles and Motorcycles
  • Intelligent Transportation Systems
  • Quiet Zones


Private highway-rail crossings are generally located on roadways not open to use by the public. Usually, an agreement between the land owner and the railroad governs the use of the private crossing. Typical types of private crossings are as follows:

  • Farm crossings that provide access between tracts of land lying on both sides of the railroad
  • Industrial plant crossings that provide access between plant facilities on both sides of the railroad
  • Residential access crossings over which the occupants and their invitees reach private residences from another road, frequently a public road paralleling and adjacent to the railroad ROW
  • Utility access crossings over which a utility company or public authority reach electric, sewer, water, flood control, or other facilities from another road
  • Temporary crossings established for the duration of a private construction project or other seasonal activity
  • In some instances, changes in land use may result in a need for the private crossing to become a public crossing. If the public uses a crossing, appropriate traffic control devices should be installed for warning and guidance. Usually the conversion of a private crossing will be governed by a construction and maintenance agreement with the public road authority and the railroad. Some State laws may have minimum traffic control device requirements that apply to the conversion of a private crossing to a public crossing. However, State and federal funds are generally not available for use at private crossings.

As with public crossings, the first option to be considered for improving private crossings is closure. Adjacent public crossings should be evaluated to determine if they can be used instead of the private crossing. Every effort to close the crossing should be made.

Some private crossings have sufficient train and roadway traffic volume to necessitate active traffic control devices. Considerations for the installation of these devices are the same as for public crossings. Federal funds and, often, State funds cannot be used for the installation of traffic control devices at private crossings. The railroad and the landowner usually come to an agreement regarding the financing of the devices.


There are numerous short line railroads, and the number is growing due to federal deregulation. Short line railroads are typically Class III railroads, as defined by the STB. Class III railroads include all switching and terminal companies and all line-haul railroads that have annual operating revenues of less than $35,809,698 million (as of 2017).(60) Many of these short line railroads provide switching and terminal services for the larger Class I and II railroad companies. Many short line railroads are members of the American Short Line and Regional Railroad Association (ASLRRA). The ASLRRA provides liaison with governmental agencies, serves as a source for information and assistance, and provides other benefits to short-line railroads.

Ownership of these smaller rail lines varies from State or local governments, port authorities, other short lines, private entrepreneurs, and shipper groups. Many new owners of short lines are keenly aware of the costs of line acquisition, track and rolling stock rehabilitation, and other operational expenditures. However, new operators may be unaware of the substantial expenditures needed for rebuilding crossing surfaces, renewing older traffic control systems, and maintaining them.

Costs associated with crossings may constitute a considerable portion of the limited annual maintenance-of-way budgets of short-line railroads. An abandoned plant, when acquired by the new owner, may not be in good condition. The track condition may be adequate, requiring little annual expense in comparison to other plant needs. Therefore, as annual track maintenance costs are reduced, crossing expenditures may constitute as much as 50 percent of the annual maintenance-of-way budget over a period of years. This depends on factors such as the location of the line in relation to population centers and the volume of heavy truck traffic.

On short-line railroads, there is often a lack of specialized personnel in-house for handling crossing responsibilities, such as the continuing maintenance of highly complex electronic grade crossing warning systems.

Although rail traffic on smaller lines tends to be sparse, as well as slow, grade crossing safety on smaller lines is no less important than those on larger railroads. National statistics indicate that the vast majority of crossing collisions occur at relatively low train speeds.

Adequate planning is essential to ensure the proper formation of new short line railroads and to improve their survival as a necessary part of the U.S. transportation system. State agencies can assist by informing short line railroads of the requirements for improving crossings on their system and direct them to other appropriate sources of information. State agencies should ensure that the short line railroads operating in their State are included in the lines of communication regarding crossings. Short line railroads also should be encouraged to participate in other crossing safety programs, such as Operation Lifesaver.


Where LRT and Busways are separated from highway facilities, their design and operations can be very similar. These parallels can be seen in the configuration, signage, and policy guidance recommended for each type. It is important to note where an FTA-regulated rail service operates in a "shared corridor" with conventional rail, FRA regulations apply at crossings. The National Transit Database (NTD) is a valuable resource of data regarding operation and safety data for transit operations. The following section highlights some important considerations for both LRT and busway crossings.

Table 10 presents typical issues and possible solutions at LRT crossings through which Light Rail Vehicles (LRVs) operate. These issues are separated into five categories: system design, system operations, traffic signal placement and operations, automatic gate placement, and pedestrian control.

Table 10. Possible Solutions to Observed Problems at LRT Crossings

Issue Possible Solution
1. System design
Vehicles driving around closed automatic gates.

Install raised medians with barrier curbs.

Install channelization devices (tubular posts, vertical delineators).

Install longer automatic gate arms.

Photo enforcement.

Four-quadrant gates.

For parallel traffic, install protected signal indications or LRV-activated "NO RIGHT/LEFT TURN" signs (R3-1, 2).

For parallel traffic, install turn automatic gates.

LRV operator cannot visually confirm if gates are working. Install gate indication signals or in-cab wireless video link. Install and monitor at a central control facility a Supervisory Control and Data Acquisition system.
Slow trains share tracks/ crossings with LRVs and near-side LRT station stops. Constant warning time. Use gate delay timers.
Motorist disregard for regulatory signs at LRT crossings and crossing warning devices. Avoid excessive use of signs. Photo enforcement.
Motor vehicles queue back across LRT tracks from a nearby intersection controlled by STOP signs (R1-1). Allow free flow (no STOP sign) off the tracks or signalize intersection and interconnect with crossing.
Sight distance limitations at LRT crossings. Maximize sight distance by limiting potential obstructions to 3.5 feet in height within about 100 to 200 feet of the LRT crossing (measured parallel to the tracks back from the crossing).
Motor vehicles queue across LRT tracks from downstream obstruction. Install "DO NOT STOP ON TRACKS" sign. Install "Keep Clear" zone striping. Install queue cutter signal. [See also "Do Not Block Intersection Markings" from MUTCD Section 3B.17].
Automatic gate and traffic signal interconnect malfunctions. Install plaque at crossing with 1-800 phone number and crossing name and/or identification number. [See also Emergency Notification Signs from MUTCD Section 8B.19].
2. System operations

Freight line converted to, or shared with, light-rail transit.

For new LRT systems, initially operate LRVs slower, then increase speed over time.
Collisions occur when second LRV approaches pedestrian crossing. When practical, first LRV slows/stops in pedestrian crossing, blocking pedestrian access until second, opposite direction LRV enters crossing.
Motorists disregard crossing warning devices. Adequately maintain LRT crossing hardware (routinely align flashing-light signals) and reduce device "clutter."
Emergency preparedness. Training of staff and emergency response teams (fire, police, EMS).
3. Traffic signal placement and operation
Motorists confused about conflicting flashing-light signal and traffic signal indicators. Use traffic signals on the near side of the LRT crossing (pre-signals) with programmable visibility or louvered traffic signal heads for far-side intersection control. Avoid using cantilevered flashing-light signals with cantilevered traffic signals.
Track clearance phasing. Detect LRVs early to allow termination of conflicting movements (pedestrians).
Excessive queuing near LRT crossings. Use queue prevention strategies, pre-signals.
Turning vehicles hesitate during track clearance interval. Provide protected signal phases for through and turning motor vehicles.
Vehicles queue back from closed gates into intersection. Control turning traffic toward the crossing.
LRT crosses two approaches to a signalized intersection (diagonal crossing). Detect LRVs early enough to clear both roadway approaches and/or use pre-signals or queue cutter signals. Delay the lowering of the gates that control vehicles departing the common intersection.
Motorists confused about gates starting to go up and then lowering for a second, opposite direction LRV. Detect LRVs early enough to avoid gate pumping (also allows for a nearby traffic signal controller to respond to a second LRV preemption). At near-side station locations, keep gates raised until LRV is ready to depart.
LRT versus emergency vehicle preemption. At higher-speed LRT crossings (speeds greater than 55 km/hr. (35 mph)), LRVs receive priority and emergency vehicles second priority.
Turning motorists violate red protected left-turn indication due to excessive delay. Recover from preemption to phase that was preempted.
With leading left-turn phasing, motorists violate red protected left-turn arrow during preemption. Switch from leading left-turn phasing to lagging left-turn phasing.
4. Automatic gate placement
At angled crossings or for turning traffic, gates descend on top of or behind motor vehicles. Install gates parallel to LRT tracks. Install advanced traffic signal to control turning traffic.
5. Pedestrian control
Limited sight distance at pedestrian crossing. Install pedestrian automatic gates (with flashing-light signals and bells (or alternative audible device)).
Pedestrians dart across LRT tracks without looking. Install warning signs. Install swing gates.
Pedestrians fail to look both ways before crossing tracks. Channel pedestrians (Z-crossings). Paint LRT directional arrow between tracks.
Pedestrians ignore regulatory and warning signs. Mount signs lower, but in accordance with MUTCD requirements, so they are closer to average eye level for pedestrians. Install active pedestrian warning devices. Provide education and enforcement.
Pedestrians stand too close to tracks as train approaches crossing. Install pedestrian stop bar with tactile warning outside of the dynamic envelope.
Pedestrians and bicyclists routinely cross the LRT tracks behind the automatic gate mechanism while it is activated. Install positive control behind the sidewalk (if present) or roadway shoulder.

Source: Korve, Hans W., Brent D. Ogden, Joaquin T. Siques, Douglas M. Mansel, et al. Light Rail Service: Pedestrian and Vehicular Safety. Washington, DC.: Transit Cooperative Research Project Report 69, Transportation Research Board, 2001.


Special consideration should be given to highway-rail crossings on high-speed passenger train routes. The potential for a catastrophic collision injuring many passengers demands special attention. This not only includes dedicated routes with train speeds over 79 mph, but also other passenger routes over which trains may operate at speeds higher than freight trains, see Table 11.

Variations in warning time may occur with high-speed passenger trains at crossings equipped with active crossing warning devices. Because of the wide variation in train speeds (passenger trains versus freight trains), train detection circuitry should be designed to provide the appropriate advance warning for all trains.

All crossings located on high-speed rail corridors should either be closed, grade separated, or if remaining at grade, equipped in accordance with FRA recommended policies summarized below. The train detection circuitry should provide constant warning time. Where feasible, other site improvements may be necessary at these crossings. Sight distance should be improved by clearing all unnecessary signs, parking, and buildings from each quadrant. Vegetation should be periodically cut back or removed. Improvements in the geometries of the crossing should be made to provide the best braking and acceleration distances for vehicles.

The FRA Highway-Rail Grade Crossing Guidelines for High-Speed Passenger Rail (61), address the following topics:

  • Consolidation and Grade Separation
  • Safety Improvements at Private Crossings ^ Creation of "Sealed Corridors"
  • Warning Systems and Other Highway Traffic Control Devices
  • Train Control Integration
  • Barrier Systems
  • Pedestrian and Trespass Considerations
  • Systems Approach

The "Sealed Corridors" approach involves a diagnostic process to assess the appropriate level of safety improvement needed for existing grade crossings which may include closure/ consolidation, enhanced warning devices, medians, and grade separation. For public highway-rail grade crossings within a "sealed corridor," FRA expects highway authorities will consider installing equipment such as (a) four-quadrant gates, (b) three-quadrant gates (exit gate on one side with a 100-foot minimum non-traversable median on opposite side), (c) 100-foot minimum non-traversable medians, or (d) paired one-way streets. Similarly, FRA expects diagnostic teams will evaluate private crossings for closure or treatment with active warning systems, such as flashing-lights and gates or a locked gate system interlocked with the railroad signal system.

Table 11. Potential Tier Structure for Passenger Systems at Highway-Rail Crossings

Service Description Feeder Regional Core Express Core Express
Speed Range (mph) 0-90 91-110 111-125 126-150 126-220
Other Traffic Allowed on Same Track Mixed Use (passenger and freight) Mixed Use Mixed Use Mixed Use Dedicated ROW
Maximum Track Class Class 5 Class 6 Class 7 Class 8 Class 9
Signals and Train Control PTC PTC + vital perimeter protection PTC + vital perimeter protection PTC + HSR-125 PTC + HSR-125
Public Highway-
Rail Grade Crossing Treatments
Automated warning; supplementary measures or sealed corridor treatments where necessary Sealed corridor; evaluate need for presence detection and PTC feedback

Barrier/warning systems required per §213.247;

Presence detection tied to PTC

None above 125 mph None above 125 mph
Private Highway-
Rail Grade Crossing Treatments
Automated warning or manually locked gate preferred; cross-buck and stop or yield sign where conditions permit Automated warning or locked gate with signal interlock

Barrier/warning systems required per §213.247;

Presence detection tied to PTC

None above 125 mph None above 125 mph

Source: Highway-Rail Grade Crossing Guidelines for High-Speed Passenger Rail, FRA, 2009, as updated to reflect subsequent changes in FRA allowable maximum speeds.

Special attention should be given to the interconnection of grade crossing warning systems with other traffic control systems, where applicable. This is to ensure that the traffic/railroad preemption timing is sufficient to safely clear vehicular traffic away from the crossing prior to the activation of the grade crossing flashing-lights and gates. A traffic engineering study should be conducted to determine the appropriate timing for the interconnection; whether the interconnection should be simultaneous or advanced preemption. The use of pre-signals and queue-cutter signals should also be explored where warranted.

Vehicle Presence Detection (VPD) technology should be considered when four-quadrant gates are present. At highway-rail grade crossings that are near highway-highway crossings, with vehicular storage constraints present, VPD should be provided in connection with the train control system when train speeds above 100 mph are present with crossings equipped with non-traversable medians.

As stated in the 2009 Highway-Rail Grade Crossing Guidelines for High-Speed Passenger Rail, the use of Remote Health Monitoring (RHM) technology at grade crossings on highspeed rail lines is clearly indicated. RHM allows immediate reporting to the railroad signal's trouble desk (or railroad dispatcher) when an intermittent malfunction or a complete failure of the grade crossing signaling system occurs. RHM provides for the continuous monitoring of the crossing system's health performance. Once a failure is detected and reported, the system enables responsive action by dispatchers, train crews, and signal maintainers to diagnose and correct the problem.

Special signing might also be employed at these crossings to remind the public that the crossings are used by high-speed trains. The signing should be in conformance with the guidelines provided in MUTCD Section 8B.20, see Figure 64.

Figure 64. Train Speed Warning Sign - This figure is an example of what a train speed warning side looks like. It is diagonal in shape and reads, "TRAINS MAY EXCEED 80 MPH.&quuot;

Figure 64. Train Speed Warning Sign

Source: Manual on Uniform Traffic Control Devices, 2009 Edition. Figure 5F-1 Highway-Rail Grade Crossing Signs and Plaques for Low-Volume Roads, Washington, DC, FHWA, 2009.


Highway-rail crossings are designed and controlled to accommodate the vehicles that use them. Trucks and buses have unique characteristics that should be considered. The following describes the additional evaluation and design taken into consideration for trucks and buses at crossings.

Trucks with Hazardous Material Cargo

Crossings used by vehicles with hazardous material cargo should be considered for improvements and, in turn, these improvements should consider the special needs of these vehicles.

Based upon various NTSB studies of collisions involving trucks including those carrying hazardous materials, the following guidance should be considered:

  • Trucks carrying bulk hazardous material should use routes that have grade separations or active control devices. Where routes that have crossings with only passive control devices are near terminals, the crossings should be considered for upgrading to active control.
  • Ensure that active warning devices are activated with enough "warning time" (activation in advance of the arrival of a train) so that trucks have the available distance required for stopping. Also, for vehicles stopped at the crossing when signals are not operating, adequate warning time should be provided for clearance of tracks by loaded trucks before the arrival of a train.
  • If feasible, where there is an intersection near the crossing, increase the storage space (defined as the "clear storage distance" in MUTCD) between the tracks and the intersecting highway. If on a direct route to a truck terminal, also consider giving ROW to the critical movement through control measures.
  • Promote a program of education and enforcement to reduce the frequency of hazardous driving and alert the driver of potential danger. Driver training and education programs such as Operation Lifesaver should be expanded to include a specific program that addresses the problems.
  • At crossings where a significant volume of trucks is required to stop, consideration should be given to providing a pull-out lane. These auxiliary lanes allow trucks to come to a stop and then to cross and clear the tracks without conflicting with other traffic. Hence, they minimize the likelihood of rear-end collisions or other vehicle-vehicle collisions. They would be appropriate for two-lane highways or for high-speed multilane highways.


Because buses carry many passengers and have performance characteristics like large trucks, these vehicles also need special consideration. Many of the measures suggested for trucks with hazardous material apply to buses. Railroad-highway crossings should be taken into consideration when planning school bus routes.

Potentially hazardous crossings, such as those with limited sight distance or horizontal or vertical alignment issues, should be avoided if possible. Crossings along school bus routes should be evaluated by the appropriate highway personnel to identify the need for improvements. Drivers should be instructed on safe crossing procedures and routes.

In addition to the recommendations that apply to trucks with hazardous cargo, the following should be considered when evaluating crossings where buses are likely to cross regularly:

  • Special training for bus drivers
  • Pavement markings and stop lines to delineate where buses should stop when checking for possible on-coming trains

Long and Heavily Laden Trucks

Large trucks have problems at crossings because of their length and performance characteristics. Longer clearance times are required for longer vehicles and those slow to accelerate. Also, longer braking distances become necessary when trucks are heavily laden, thus reducing their effective braking capability.

As truck sizes, configurations, and weights have increased over time, it is critical to address currently allowable large vehicles (such as the interstate semitrailer truck–WB-62 or WB-65), where such vehicles may be expected to utilize a highway-rail crossing on a regular basis. Consequently, when considering improvements, the designer should be aware of and design for the amount and type of current and expected truck traffic. Areas that should be focused upon include the following:

  • Longer sight distances
  • Placement of advance warning signs
  • Warning time for signals
  • Approach and departure grades
  • Storage area between tracks and nearby highway intersection


The configuration of each trail-rail intersection is unique. There are available reference guides, but solutions should be adapted to site conditions using standard treatments, where applicable. The FRA, State DOTs, and Class 1 railroads are working to close existing at-grade rail crossings to reduce liability, exposure, and incidents.

To enhance visibility of the trail-rail intersection for approaching cyclists and other trail users, advance notice of the crossing should be displayed via pavement markings and signage. Allowing the cyclists enough time to assess the situation and choose whether to clear the intersection or stop prior to entering the crossing. The angle of the trail-rail crossing is another critical issue. Right-angle crossings are preferred. Where unable to meet these criteria (crossing angle is less than 45 degrees) additional width should be provided near the crossing. Figure 65 illustrates this guidance.

Figure 65. Design for Degree of Trail-Rail Crossing - This figure gives two designs for different degrees of Trail-Rail crossings. The first figure, 5.20, has a 45 degree trail-rail crossing. The trail has a maximum width of 4.2 meters (14 feet). There needs to be a Crosshatch with a STOP sign both on the same post placed at the top of both ROW fences on both sides of the railroad track. The second figure, 5.21, has a 90 degree trail-rail crossing. The trail has a maximum width of 4.2 meters (14 feet). Ther

Figure 65. Design for Degree of Trail-Rail Crossing

Source: Adapted from Rails-with-Trails: Lessons Learned, Literature Review, Current Practices,

Conclusions, USDOT, FTA, FHWA, FRA, August 2002.

The crossing surface type will likely impact cyclists as well. Depending on the angle and type of crossing, a cyclist may lose control if the wheel becomes trapped in the flangeway. The surface materials and the flangeway width and depth should be evaluated. The more the crossing deviates from the ideal 90-degree crossing, the greater the potential for a cycle wheel to be trapped in the flangeway. If the crossing angle is less than 45 degrees, consideration should be given to widening the bikeway to allow sufficient width to cross the tracks at a safer angle.

For signing and markings at a crossing intended for use by bicyclists, refer to Figure 48, which shows the MUTCD treatment for a pathway crossing.


ITS extends into applications that can be implemented at railroad crossings and within vehicles which will affect traffic signal preemption. Typically, trains have the ROW at crossings, and the crossings are managed to maximize safety of all users while minimizing delay to roadway traffic. This involves the coordination of railroad active safety devices with highway traffic signals, as well as the dissemination of crossing status information to aid in route planning. The advancement of ITS applications can enhance these capabilities for all parties involved.

ITS National Architecture and User Service 30

Per FHWA, "National ITS Architecture (also "national architecture") means a common framework for ITS interoperability. The National ITS Architecture comprises the logical architecture and physical architecture which satisfy a defined set of user services. The National ITS Architecture is maintained by the USDOT and is available on the DOT website.(62)

The FHWA, in conjunction with FRA, has developed "User Service 30" to describe the ITS applications that relate to the highway-rail crossing. These ITS applications have been defined in the National ITS Architecture, which is a framework for developing integrated transportation systems. The National ITS Architecture defines a set of "subsystems," "terminators," and "architecture flows" that describe the transfer of information between ITS systems.

Subsystems are the building blocks of the National ITS Architecture that perform the ITS functions identified in 33 user services (which include the highway-rail crossing user service). Terminators are systems that interface with the ITS systems. Architecture flows are the definition of the information that is passed between subsystems or between subsystems and terminators. In the context of the National ITS Architecture, highway-rail crossing functions are identified with the following three interfaces (refer to Figure 66):

  • Roadway subsystem and the wayside equipment terminator
  • Traffic management subsystem (TMS) and the rail operations terminator
  • Highway-rail intersection data, traffic management to roadway
Figure 66. Highway Rail Intersection Interface Overview - This figure shows a visual reference of the Highway Rail Intersection Interface Overview. The first figure is of the Railroad system. The images in this figure are TRACK CIRCUITS, a train on a railroad, a WAYSIDE EQUIPMENT TERMINATOR, and AUTOMATIC GATES/BARRIERS. The RAIL OPERATIONS TERMINATOR crossfunctions with the TRAFFIC MANAGEMENT SYSTEM, which is part of the second figure. This second figure is the Roadway system. The images in this figure are

Figure 66. Highway Rail Intersection Interface Overview

Source: The National Architecture for ITS, USDOT.

Roadway subsystem and the wayside equipment terminator. The roadway subsystem represents ITS field equipment, including traffic control signal controllers. The wayside equipment terminator represents train interface equipment (usually) maintained and operated by the railroad and (usually) physically located at or near a crossing. The roadway subsystem interface with the railroad wayside equipment will provide crossing status and blockage notification to wayside equipment and, conversely, real-time information about the approach (actual or predicted) of a train to the roadway subsystem. The interface operates as follows:

  • The roadway subsystem sends the real-time crossing status to the wayside equipment. This includes a confirmation that the crossing is closed (gates are down) and that trains may proceed at full authorized speed.
  • The roadway subsystem also sends a real-time indication of intersection blockage. This message would be used to provide the information needed by the wayside equipment to alert the train to reduce speed or stop.
  • The wayside equipment provides a real-time indication of its operational status via the track status flow. This would alert the roadside equipment to possible failures or problems in the wayside equipment. The track status flow also includes the simple binary indication of a train approaching, which is currently used when traffic control signal controller units are interconnected with the wayside equipment.
  • In future implementations, the wayside equipment would provide expected time of arrival and length of closure via an arriving train information flow.

TMS and the rail operations terminator. The interface between the rail operations terminator and TMS provides for the exchange of management or near real-time data between these two key functions.

  • The rail operations function will send information to the TMS to support forecasting of crossing closures. This includes train schedules and crossing maintenance schedules. In addition, the rail operations function will send to the TMS information about rail incidents that may impact vehicle traffic. This latter information would be in near real time; other schedule information would be provided on a periodic basis (such as daily).
  • The TMS would notify the rail operations function in near real time about equipment failure, intersection blockage, or other incident information (such as a nearby hazardous material spill). The TMS would also send information about planned maintenance activities occurring at or near the crossing that would impact the railroad ROW.

Roadway subsystem and TMS. Beginning in 2011, FRA began researching connected vehicle concepts appropriate for highway-rail crossings. The primary objective of this research is to explore the feasibility of in-vehicle safety concepts capable of providing an alert of an approaching train to a highway vehicle approaching a highway-rail crossing. The technology is intended to be deployed at any highway-rail crossing where benefit would be accrued by increasing situational awareness to minimize safety related incidents or improving the flow of roadway traffic.

A set of the following potential scenarios were initially identified and evaluated for future implementation:

Highway-rail crossing equipped with active warning devices. Connected vehicle roadside equipment is activated by the highway-rail crossing signaling system preemption signal by means of a hardwire interconnection. Approaching highway vehicles received alerts over the connected vehicle Dedicated Short Range Communications (DSRC) communications channel.

Trains equipped with advanced technology. This scenario would utilize emerging train positioning technology. Connected vehicle roadside equipment could receive train location information over the 220MHz communications network and provide alerts to approaching highway vehicles over the connected vehicle DSRC communications channel.

Highway-rail crossing not equipped with active warning devices. A train is equipped with connected vehicle onboard equipment that allows it to transmit over a DSRC communications channel directly with highway vehicles. This is the only scenario that is dependent upon the installation of connected vehicle technology on trains.

To this end, FRA has been exploring the feasibility of the first scenario and has developed concept of operations and system requirements documents to support this approach. Proof-of-concept testing was performed in 2017 on a DSRC-based platform, but the effort remains in the exploratory phase.

Standard 1570

The Institute of Electrical and Electronics Engineers (IEEE) empaneled a working group that developed IEEE Standard 1570, "Standard for the Interface Between the Rail Subsystem and the Highway Subsystem at a Highway Rail Intersection."(63) This standard was developed to coordinate information transfer between the two with emphasis on digital data communication and to enable interoperability among the various types of equipment.



The FRA regulations on quiet zones allow localities nationwide to mitigate the effects of train horn noise, while maintaining a high level of safety at grade crossings located within quiet zones.(5) These regulations were developed to provide a consistent approach nationwide to enable local jurisdictions to establish quiet zones without compromising safety. They address use of the horn at public highway-rail grade crossings.

The public authority responsible for traffic control or law enforcement at the highway-rail grade crossing is the only entity authorized to establish a quiet zone.

FRA regulations on quiet zones:

  • Define engineering solutions known as "supplementary safety measures" (SSMs) for use at highway-rail grade crossings without FRA approval.
  • Provide explicit flexibility for the modification of SSMs to receive credit as "alternative safety measures" (ASMs).
  • Include a provision that provides risk reduction credit for pre-existing SSMs and pre-existing modified SSMs that were implemented prior to December 18, 2003.
  • Allow use of education and enforcement options, including photo enforcement, subject to verification of effectiveness.

Public authorities may establish quiet zones in which train horns will not be routinely sounded at grade crossings. The details for establishment of quiet zones differ depending on the type of quiet zone to be created (pre-rule or new) and the type of safety improvements to be implemented (if needed).

FRA regulations governing quiet zones (49 CFR Part 222) also:

  • Allow establishment of quiet zones that prohibit sounding of horns during the nighttime hours only. These quiet zones are referred to as partial quiet zones.
  • Require diagnostic team reviews of pedestrian crossings and private crossings that provide access in active industrial or commercial sites, if the pedestrian and private crossings are located within proposed new quiet zones.
  • Require that public authorities retain automatic bells at public highway-rail grade crossings subject to pedestrian traffic.
  • Require public authorities to provide notification of their intent to create a new quiet zone. During the 60-day period after the Notice of Intent is mailed, comments may be submitted to the public authority.
  • Require that public highway-rail grade crossings located within a Quiet Zone comply with applicable MUTCD provisions.

Once a quiet zone is established, the railroad is generally barred from routine sounding of the horn at the affected grade crossings. However, railroads remain free to use the horn for other purposes as prescribed in railroad operating rules on file with FRA. In addition, railroads must use the horn as specified in other FRA regulations (see 49 CFR 222.23), even within quiet zones.

The FRA provides a web-based tool for communities to use in performing "what if" calculations and preparing submissions necessary to create or retain quiet zones. This tool, the Quiet Zone Calculator, may be found on FRA's website.(64)

The FRA regional personnel are available to participate in diagnostic teams evaluating options for quiet zones.

Requirement to Sound the Locomotive Horn

Outside of quiet zones, railroads must sound the horn 15-20 seconds prior to a train's arrival at a public highway-rail grade crossing, but not more than one-quarter-mile in advance of the crossing (49 CFR 222.21).

Note: Before 49 CFR Part 222 was issued, State laws and railroad rules generally required that the locomotive horn begin sounding from a point one-quarter-mile in advance of the highway-rail grade crossing and continue sounding until the crossing is occupied by the lead locomotive of a train. For trains operating at less than 45 miles per hour, FRA's current regulations in 49 CFR Part 222 reduce the time and distance over which the horn is sounded, thereby reducing noise impacts on local communities.

The required pattern for sounding the horn is two long, one short, and one long blast repeated or prolonged until the lead locomotive occupies the public highway-rail grade crossing. Train operators may vary this pattern as necessary where public highway-rail grade crossings are closely spaced; they are also authorized (but not required) to sound the horn in the case of an emergency, even in a quiet zone.

The FRA regulations in 49 CFR 229.129 also prescribe a minimum and a maximum volume level for the train horn. The minimum level is 96 dB(A), and the maximum volume level is 110 dB(A).

Creation of Quiet Zones

The rule provides significant flexibility to communities to create quiet zones. This flexibility extends to communities that had existing whistle bans, as well as other communities that previously did not have an opportunity to restrict locomotive horn sounding at grade crossings.

It should be noted that 49 CFR Part 222 permits implementation of quiet zones in low-risk locales without requiring the addition of safety improvements.

  • This concept utilizes a risk index approach that estimates expected safety outcomes (that is, the likelihood of a fatal or non-fatal casualty resulting from a collision at a highway-rail crossing including the existing risk caused by the absence of the sounding of the locomotive horn)
  • Risk is averaged over the public highway-rail grade crossings in a proposed quiet zone. This averaged risk is called the Quiet Zone Risk Index (QZRI)
  • The QZRI within the proposed quiet zone is then compared with the average nationwide risk at gated public highway-rail grade crossings where the horn is sounded (the "Nationwide Significant Risk Threshold" [NSRT]). FRA periodically revises the NSRT

The effect of this approach is that it may be possible to establish quiet zones without significant expense if flashing-lights and gates are already in place at the public highway-rail grade crossings. Typically, these quiet zones have few trains traveling at low speeds.

If the QZRI for a proposed new quiet zone exceeds the NSRT and the level of risk when horns are routinely sounded within the proposed quiet zone, SSMs or ASMs will need to be used to reduce that risk (to fully compensate for the absence of the train horn or to reduce risk to a level below the NSRT).

Establishment of New Quiet Zones

New quiet zones may be established if all public highway-rail grade crossings within the proposed quiet zone are equipped with flashing-lights and gates; and either of these following specifications:

  • The QZRI within the proposed quiet zone is less than the NSRT >• SSMs are present at each public highway-rail grade crossing
  • Safety improvements (SSMs or ASMs) are made to compensate for loss of routine sounding of the train horn
  • Safety improvements (SSMs or ASMs) are made to reduce the QZRI within the proposed quiet zone to a level below the NSRT

Note: FRA regulations (49 CFR 222.35) require that the active warning system at each public highway-rail grade crossing within a quiet zone consist of flashing-lights and gates be equipped with power-out indicators, which provides information on the presence of commercial electrical power at the crossing. FRA regulations also require that the active crossing warning system be equipped with constant warning time train detection, if reasonably practical. Detailed instructions for establishing a quiet zone are available on FRA's website.(65)

Length of Quiet Zones

FRA regulations require that a quiet zone be at least one-half-mile in length and include at least one public highway-rail grade crossing. (See 49 CFR sections 222.9 and 222.35 for more information.)

Supplemental and Alternative Safety Measures

Supplemental Safety Measures (SSMs) are engineering improvements that have been determined by FRA to be an effective substitute for the train horn. If employed at every public highway-rail grade crossing in the quiet zone, the public authority can establish the quiet zone by designation without prior FRA approval (subject to reporting requirements). They also may be used at some public highway-rail grade crossings in a proposed quiet zone to fully compensate for the lack of warning provided by the train horn or to reduce existing risk levels to a level below the NSRT. SSMs include the following:

  • Temporary closure of a public highway-rail grade crossing (for partial quiet zone only) ^ Permanent closure of a public highway-rail crossing
  • Four-quadrant gates
  • Gates with traffic channelization arrangements (for example, non-mountable curb or mountable curb with delineators) at least 100 feet in length on each side of the crossing (or 60 feet where there is an intersecting roadway) and no commercial or industrial driveways located within 60 feet of the gate arm.
  • One-way street with gate(s) across all approaching roadway lanes

Alternative Safety Measures (ASMs) may also be applied to reduce existing risk levels at one or more public highway-rail grade crossings within a proposed quiet zone. The public authority must apply (per 49 CFR 222.39(b)) to FRA for approval of the effectiveness rate that will be assigned to each ASM proposed for use at public highway-rail grade crossings in the quiet zone. ASMs include the following:

  • Any modified SSM (such as crossing gates with traffic channelization less than 60 feet in length)
  • Education and/or enforcement programs (including photo enforcement) with verification of effectiveness
  • Engineering improvements, other than modified SSMs
  • Combination of the above

FRA regulations provide that pre-existing SSMs and pre-existing modified SSMs can also be counted toward risk reduction.

Automated Wayside Horn

49 CFR Part 222 authorizes use of the automated wayside horn at highway-rail grade crossings equipped with flashing-lights and gates (inside or outside a quiet zone) as a one-to-one substitute for the train horn.

The MUTCD Section 8C.07 provides guidance on Wayside Horn Systems at crossings.

Special Circumstances

A public authority or railroad seeking relief from a regulatory provision in 49 CFR Part 222 may request a waiver from the provision from FRA.

A railroad or public authority seeking a waiver from a regulatory provision in 49 CFR Part 222 must first consult with the other party to find out whether the other party would be willing to submit a joint waiver request. If agreement to file a joint waiver petition cannot be achieved, the party may still request the regulatory relief by a waiver, provided the waiver petition reflects the efforts of the submitting party to reach agreement with the other party and explains why a joint waiver petition would not be likely to contribute significantly to public safety.

The FRA may grant waivers if in the public interest and consistent with the safety of highway and railroad users of the highway-rail crossings.


This Handbook presents guidance and standards which are applied to develop engineered treatments intended to improve safety and operations at crossings. Sound engineering is fundamental to safety. It is acknowledged that the synergy of the "Three E's–Engineering, Education, and Enforcement" maximizes the benefits of engineering treatments. It is beyond the scope of this Handbook to provide an in-depth presentation of materials on education and enforcement, but practitioners should be aware that initiatives in these areas are fundamental to maximizing safety at crossings.


Education on crossing safety at the national level is provided by Operation Lifesaver, Inc. (OLI) as well as several Federal agencies. The OLI is a nonprofit public safety and awareness organization established in 1972, which provides educational resources, public awareness materials and community involvement activities focused on crossing safety. The OLI engages volunteers who provide training on rail crossing safety. The OLI also partners with emergency responders and local law enforcement to support initiatives to promote crossing safety. The OLI partners with the USDOT in supporting "Rail Safety Week." The first U.S. Rail Safety Week was held on September 24-30, 2017. This effort was timed to occur with the beginning of the school year when other safety initiatives take place. More information on OLI, its activities and materials can be found at its website at

Transit districts across the country promote education on crossing safety. Large urban transit districts also develop and disseminate safety-related materials within their districts using a wide range of venues. Examples include the Chicago Transit Authority "It's Not Worth Your Life. Stay off the Tracks" campaign(66), New York MTA's "Wait for the Gate" campaign(67), and Los Angeles Metro, which has developed a series of "Safetyville" videos using stick figure animation to deliver graphic reminders of transportation-related safety hazards and consequences of risky behavior.(68)


Crossing collisions occur less frequently than collisions involving highway vehicles, bicycles, motorcycles, or pedestrians, and risky behavior at a crossing does not necessarily entail a legal violation. Local initiatives and targeted enforcement campaigns have been used to enhance crossing safety. A recent example was an "enforcement blitz" conducted in Portage County, WI, involving the State patrol, local police and CN railroad police in May 2018.(69)

The Volpe Center prepared an in-depth study of enforcement campaigns in the Public Education and Enforcement Research Study (USDOT, December 2006).(70) The Public Education and Enforcement Research Study (PEERS) assessment describes two local initiatives and success factors. Improved safety was identified in the Arlington Heights, IL, initiative characterized by commuter train operations and a population of repeat crossing users versus Macomb, IL, where the rail traffic was predominantly long freight trains and the population more variable.