(This version not formatted for printing.) Guidance on the use of

Traffic Channelizing Devices

at Highway-Rail

Grade Crossings

Several types of traffic channelizing devices are

finding new application at highway-rail grade

crossings that are equipped with flashing light signals

and crossing gates. These channelizing devices,

when used appropriately, can reduce the risk of a

collision between a vehicle and a train by 75%! This

high level of risk reduction makes traffic

channelizing devices a good choice to enhance safety

and greatly reduce gate violations at highway-rail

grade crossings. 

Each device has its own special properties and

installation requirements. This guidance is offered to

facilitate the effective use of these traffic control

devices.

The Federal Highway Administration issued the

report “Guidance on Traffic Control Devices at

Highway-Rail Grade Crossings.” Channelizing

devices may be grouped in a few general categories.

BARRIER WALL SYSTEMS

Concrete barriers and similar proprietary systems are

substantial, and may require a wide space between

opposing lanes of traffic on approach to the grade

crossing. While these are the most effective at

deterring “drive-around” gate violations, their large 
size may preclude their use in many applications. 

In addition, the upstream end of a barrier must be

equipped with a site-appropriate energy absorbing

end treatment. For this reason, this class of device

can be more cost effective where continuous runs of

150 feet or more may be achieved.

WIDE RAISED MEDIANS

In special situations where median width is available,

a raised median of between four and 100 feet in

width may be employed. Such a wide median may

prove effective in deterring gate violations, even

though it does not actually constitute a true barrier as

commonly defined. 

In addition, a well-landscaped wide median will also

provide aesthetic benefits to the surrounding

neighborhood. A wide median, if attractively

landscaped, is often the most aesthetically pleasing

separation method. 

NON-TRAVERSABLE CURB ISLANDS

This class of device has the advantage of a narrower

footprint, but its use should be restricted to approach

roadways with posted speeds of 40 MPH or below. 

These devices are substantial enough that each

installation should be carefully designed, as an

inappropriately placed device can constitute a hazard

if struck by an errant vehicle. These devices are

generally from six to nine inches in height, and

usually about 2 feet wide. They should be equipped

with reboundable, reflectorized vertical panels, to

enhance device visibility, and to increase “drivearound” deterrence. Road users would encounter

significant difficulty attempting to cross over such a

non-traversable island, because the six to nine inch

heights cannot be readily mounted by most vehicles. 

Retroreflective materials (in the color appropriate for

the direction of travel in adjacent

lanes) should be applied to the

curbs to enhance their low-light

visibility.

TRAVERSABLE RAISED

CURB SYSTEMS 

This class of channelizing device is

the narrowest, and therefore the

easiest to fit in a wide range of

roadway cross-section widths. 

Traversable raised curb systems

should always be used with

reboundable, reflectorized vertical

panels. This combination of

devices will present road users

with a visual deterrent to crossing

over into the opposing traffic lane

in order to violate lowered gates. 

The curb portion is not more than six inches in

height, and generally less than twelve inches in

width. Curbs are formed with a rounded shape that

will create minimal vehicle deflection upon impact. 

In most cases, these systems can be installed on

existing roadway centerlines, without the need for

widening the roadway approaches to the crossing

Retroreflective materials (in the color appropriate for

the direction of travel in adjacent lanes) should be

applied to the curbs to enhance their low-light

visibility.

These traversable curbs may present less of a

physical barrier to crossovers than the more

substantial devices discussed previously, but they

still provide a considerable deterrent to gate

violations. These devices can be used where

appropriate to enhance safety at a wide variety of

gated crossings.

Special care should be taken during installation of 
these devices. With proprietary systems, be careful

to ensure that all anchorages to the pavement are

completed according to the manufacturer’s

instructions or State or local standards; in addition,

be sure that the attachment of each vertical panel is

secure. Any deflectable hinges must function

properly. 

In the case of proprietary systems utilizing modular

plastic curbs with vertical panels or road tubes, these

devices should be known to have been crash tested. 

This will ensure that they do not have the potential to

send an errant vehicle out of control when struck. In

addition, the vertical elements should not separate

upon impact, nor should impacted curbs separate

from the pavement and become airborne. 

The Office of Highway Safety of the Federal

Highway Administration can supply the relevant test

criteria and procedures; see their website at: 

http://safety.fhwa.dot.gov/

APPLICABILITY FOR QUIET ZONE

ESTABLISHMENT - see FRA website at:

http://www.fra.dot.gov

The Federal Railroad Administration has recognized

these channelizing devices as qualified Supplemental

Safety Measures when used according to its

regulations for the use of locomotive horns at grade

crossings, found at 49 CFR Part 222. For purposes of

establishing a Quiet Zone under Part 222, these

devices have been assigned an effectiveness rate that

represents their ability to reduce the probability of a

collision at a grade crossing. For traversable

channelizing devices with vertical panels, the

effectiveness rate is 0.75. For non-traversable

channelizing devices, with or without vertical panels,

the effectiveness rate is 0.80. 

These values are used by the Quiet Zone Calculator

in determining the risk of a

collision at a crossing to be

included in a (new or existing)

quiet zone.