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 Approach Zone Guidelines
1. Consider the use of simple/reverse curves, S-curves, or traffic circles in the geometric
roadway design to reduce and control the speed of traffic. Ensure that any curves are
adequate to support the design vehicles (recommend minimum of AASHTO WB-50).
2. Consider the possibility of temporary barriers required by the installation AT Plan at
certain FPCONs. Many installations may use jersey barriers, water-filled plastic
barriers, or similar obstructions to reduce the number of lanes and reduce the speed of
oncoming traffic. If possible, consider the incorporation of design details to support
the installation of temporary barriers. This might include the incorporation of pre-
positioned sleeves or anchors to secure temporary bollards, etc. Any obstructions in
the roadway shall be clearly marked and identified with Type III Barricade markings
in accordance with Section 3F.01 of MUTCD.
3. Maximize the length of the approach zone, to provide optimal stacking distance for
the traffic queue.
4. Consider the use of reversible lanes to facilitate increased throughput and increased
flexibility where space is unavailable for additional lanes.
5. Where necessary and desirable perform sorting of traffic by vehicle type. One
example would be utilizing the farthest right lane for truck traffic, which facilitates the
rejection of these vehicles by supporting their larger turning radii. Sorting can also
increase throughput by separating vehicles with varying inspection requirements.
Access Control Zone Guidelines
1. Provide infrastructure to support manual and automated identification and inspection
procedures for the inbound and outbound lanes. The access control zone should be
configured to support tandem processing.
2. The main identification area will generally be covered with an overhead canopy to
protect against inclement weather, facilitate identification and inspection procedures,
and provide a platform for lighting and CCTV.
3. As illustrated by the functional diagrams shown in Figures 3.1 through 3.3 there may
be the need for several rejection points from an ECF. At a minimum two rejection
points shall be provided. One shall occur prior to the central identification area /
gatehouse and the other will occur after this point.
4. Provide a channelization island between all inbound and outbound lanes. A primary
channelization island will be located in the identification area. A secondary
channelization island will be positioned prior to the first rejection point. This island will
support the installation of future automated access control systems.
5. The access control zone will be designed to facilitate POV inspections out of the traffic
lanes. This can be accomplished with a separated lane/inspection area or through the
use of a late pull-off.
6. Each ECF will have a minimum of one gatehouse. Additional sentry booths may be
provided if required. The gatehouse can be centrally located on a median, or may
be positioned to the side of the ECF.
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