Section 3: Approving a Quiet Zone

Qualifying for a Quiet Zone

A Quiet Zone may be established without approval of the FRA
using one of the following criteria
:
  • Installation of
     one or more Supplementary Safety Measures (SSMs) at all public at-grade crossings within the Quiet Zone.
  • If
     Quiet Zone Risk Index is at or below Nationwide Significant Risk Threshold (NSRT) after any necessary SSMs are installed.
  • If Quiet Zone Risk Index
     is at or below Risk Index with Horns after any necessary SSMs are installed.
The NSRT is an average value established for all gated public crossings in the United States where train horns are sounded. It is updated annually by the FRA and published on the FRA website. Any Quiet Zones which qualify under this rule no longer qualify if a revised NSRT drops below the
Quiet Zone Risk Index
.
Local governments may also establish a Quiet Zone with approval of Alternative Safety Measures to be approved by application to the FRA.

Supplementary Safety Measures (SSMs)

A list of
 approved SSMs to be installed on all approaches to an at-grade crossing, with associated effectiveness,
is as follows
:
  • Temporary closure of at-grade crossing during hours which Partial Quiet Zone is in effect (Effectiveness: 1.0).
  • Four-quadrant gate systems with no presence detection (Effectiveness: 0.82).
  • Four-quadrant gate systems with presence detection (Effectiveness: 0.77).
  • Four-quadrant gate systems with traffic of at least 60 feet with or without presence detection (Effectiveness: 0.92).
  • Gates with channelization devices (Effectiveness: 0.75).
  • Gates with non-traversable curbs with or without channelization devices (Effectiveness: 0.80).
  • One way street with gates (Effectiveness: 0.82).
  • Permanent closure of at-grade crossing (Effectiveness: 1.0).
The effectiveness represents the ability of the SSM to reduce
at-grade
 crossing crashes. For example, closing a crossing reduces 100% of at-grade crossing crashes while installing gates with channelization devices reduces 75% of crashes. Effectiveness values are subject to change by the FRA.
The following requirements apply when installing SSMs:
  • All approach and exit lanes must be covered by gates in a four-quadrant system.
  • Horizontal distance between two gate ends must not be more than 2 feet.
  • Horizontal distance between a gate and a raised median or channelization device or curb must not be more than 1 foot.
  • Medians or channelization devices must extend at least 100 feet from gate arm, or if there is an intersection within 100 feet of gate, the median or channelization device must extend at least 60 feet from gate arm.
  • Non-traversable curbs must be 6-inches height minimum and only used when the roadway speed limit is 40 mph or less.
  • Any streets, alleys, or commercial driveways within 60 feet of at-grade crossing (parallel with rail) must be closed if medians or channelization devices are proposed.
  • Non-traversable curb must extend back 100 feet from gate if only one gate is used on a one-way street.

Alternative Safety Measures (ASMs)

ASMs may also be proposed to the FRA who will determine the effectiveness used in Quiet Zone Risk Index calculations. There are 3 types of ASMs:
  • Modified SSMs (i.e., channelization devices less than
    60-foot
     long).
  • Non-Engineering ASMs (i.e., traffic law enforcement program).
  • Engineering SSMs (i.e., engineering improvements to address sight distance).

Quiet Zone Risk Index (QZRI)

A QZRI must be calculated whenever SSMs are not installed at all crossings. To calculate a QZRI, the following procedure is followed:
  • Determine crossing Risk Index with Horns (RIWH) for each public at-grade crossing in
    proposed
     Quiet Zone prior to any adjustments for SSM effectiveness.
  • Determine Crossing Risk Index (Crossing Risk Index = RIWH * 1.668 * (1-Effectiveness)) for each public at-grade crossing in
    proposed
     Quiet Zone after any current or planned SSMs/ASMs are installed.
  • Determine RIWH (average of crossing RIWH in absence of any existing or proposed SSMs for all public at-grade crossings in Quiet Zone).
  • Determine QZRI (average of Crossing Risk Index for all public at-grade crossings in Quiet Zone).
The initial RIWH calculation may be determined from the FRA website Quiet Zone Calculator and is a calculation based on:
  • AADT.
  • Trains per day.
  • Number of day through trains.
  • Total switching trains per day.
  • Number of main tracks.
  • Number of other tracks.
  • Crossing
    location
     (urban or rural location).
  • Roadway
    surface
     (paved or
    unpaved
    ).
  • Maximum train speed.
  • Number of roadway lanes.
  • Number of years of crash data.
  • Number of crashes in crash data years.
Note that
 any existing grade separated or closed crossings may not be considered when calculating the QZRI. For any proposed closed crossings, the existing traffic counts at the crossing must be distributed among adjacent crossings for AADT calculations.

Wayside Horns

Wayside horns may be used in place of locomotive horns at individual or multiple at-grade crossings within Quiet Zones and are considered
an even
 substitution for train horns. The wayside horn is a stationary horn located at a rail-highway at-grade crossing which directs noise down the roadway rather than at surroundings. Any at-grade crossing with a wayside horn is not considered when calculating the QZRI.

TxDOT Review

RRD
 is mailed a copy of an NOI by the local government
or city. RRD
 forwards the NOI to the district railroad coordinator for any comments and compiles these comments with any comments from
RRD
 for response to the local government.
NOIs are reviewed to ensure the proposed Quiet Zone:
  • Meets requirements described in this chapter.
  • Meets requirements typically included on FSP projects.
  • Is calculated correctly if the Quiet Zone applies because the QZRI is less than or equal to the RIWH or NSRT.
  • Individual crossing data (traffic counts, train counts, etc.) is correct if the Quiet Zone applies because the QZRI is less than or equal to the RIWH or NSRT.
  • Includes all crossings along the section of rail indicated as shown in TRIMS.
For more information on reviewing plan sets, see Chapter 7.
Any data discrepancies noted between the NOI and TRIMS are verified between
RRD
, the local government and the railroad company.
RRD
 coordinates any inventory updates in TRIMS and with the FRA.

Application to the FRA

If any ASMs are included on the NOI, the local government will submit an application to the FRA for approval of the proposed Quiet Zone.
The following parties are provided a copy of the application to the FRA by the local government:
  • Railroad companies operating on crossings within Quiet Zone.
  • TxDOT (acting as state
    government or city
     responsible for grade crossing and road safety).
  • Any private landowners with private crossings within Quiet Zone.
  • Any other government agencies
    or cities
     with jurisdiction over public crossings within the Quiet Zone.
The application must include:
  • Inventory forms for all crossings prior to any Quiet Zone upgrades. Any changes to reported inventory information must be transmitted to
    RRD
    .
  • Explanation of safety improvements local government will implement to qualify for the proposed Quiet Zone.
  • Copy of recommendations of diagnostic team and list diagnostic inspection
    attendees
    .
  • Copy of comments from TxDOT and all operating railroad companies in response to the NOI and response to these comments.
  • Commitment to implement proposed safety improvements.
  • Data analysis showing proposed improvements will reduce QZRI below NSRT or RIWH.
  • 5 year projected vehicular and rail traffic counts for any new crossings located within proposed Quiet Zone.