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Part Two - Law Enforcement Escorts

Task Details

This section presents the details for each task in the Best Practices Guidelines for law enforcement escorts involved in the safe movement of permitted oversize/overweight loads.

Task #1: Prepare for the escort.

A. Obtain a copy of all permits.

When law enforcement escorts are preparing to escort an oversize/overweight shipment, they should begin by
obtaining a copy of all permits. The permitting agency is responsible for setting the specific requirements for
issuing permits. Basically, permits are required when the vehicle exceeds the legal weight limit and/or the vehicle exceeds the legal size limit.

Multiple permits often accompany oversize/overweight movements. The escort requirements vary based on the load and the jurisdiction. Permits issued by the state’s Department of Transportation usually do not authorize travel on city streets. Such authority must be obtained from the city/municipality prior to movement of the permitted load.

A consistent set of guidelines should be in place to determine when pilot car escorts and law enforcement escorts are required. It seems reasonable to require law enforcement escorts on two-lane highways if the vehicle and load exceeds 12 feet in width. On multilane highways, law enforcement escorts should be required if the vehicle and load exceeds 14 feet in width.

States should work toward centralized and computerized permit systems, and neighboring states with mutually
agreed-upon limits should consider regional permit issuance.

To prepare for the escort, law enforcement officials must receive a copy of all permits relating to that movement. It is recommended that a designated official review all permits and make law enforcement escort assignments. This designated official shall be called the “coordinating officer” for that escort. The coordinating officer may suggest recommendations and special conditions of the permit.

B. Verify the load is the size and weight stated in the permit.

The coordinating officer should verify the size and weight of the oversize/overweight load, ensuring that it
matches the size and weight stated on the permit. In addition, the ground clearance and wheel base measurements must be verified. When possible, it is recommended this is done when the permit is received by law enforcement personnel, before the day of the escort so measurement disputes may be resolved.

MEASURING HEIGHT

If it seems the height of the vehicle or load is over the permitted limit, the assessment of its height must meet a standard of accuracy. Below is an example of taking the physical measurement of height when there are two
officers present:

  • Standing away at the side of the vehicle, an enforcement officer identifies the highest point of the vehicle or the load. If the ground is uneven at this point then the officer should ask the driver to move the vehicle.
  • The telescopic measuring pole is held against the side or end of the vehicle at the highest point of the vehicle or its load.
  • When the second officer confirms that the pole is placed and extended correctly, the officer holding the pole reads the height indicated on the pole.

An officer who is working alone can tie the height measuring pole to the tie rail at the side of the trailer. He or
she will have to go back and forth checking for the top of the vehicle or load and making the necessary
adjustments to the height of the pole.

MEASURING WIDTH

If it seems the width of the vehicle or load is over the permitted limit, the assessment of its width must meet a
standard of accuracy. Any method of assessing width must avoid tape sag as a potential source of error, e.g. by measuring along the ground or along the rail. Two methods for measuring width are described below: the
Projection-vehicle-projection method and the Single measure method. The Single measure method is suitable
when there is a projection from only one side of the vehicle or where the widest point of projection on each side is at the same distance along the length of the vehicle.

Projection-vehicle-projection method

  • By line of sight, or by using a plumb bob, measuring pole or tape if necessary, identify the widest point of
    the vehicle or load.
  • If the projection is flat and accessible, e.g. a pallet that extends over the side of the vehicle, hold the tape
    against the edge of the projection and measure to the side of the vehicle.
  • If the widest point is out of easy reach, e.g. a piece of mining equipment high off the ground, hold the
    telescopic pole against the projection and mark the widest point to the ground. The pole should be held as
    close as practical to parallel to the side of the vehicle to avoid distortion on a sloping site. Similarly, mark
    the ground at the side of the vehicle and measure between two points on the ground.
  • The widest point and the side of the vehicle can be marked on the ground using a plumb bob if there is no
    significant slope on the inspection site.
  • Measure and record the width of the vehicle itself
  • Measure and record the width of the projection on the other side of the vehicle in the same way as the
    projection on the first side was measured.
  • Add the measured widths of the first projection, the vehicle and the second projection.

Single measure method

  • By line of sight, or by using a plumb bob, measuring pole or tape if necessary, identify the widest point of
    the vehicle or load.
  • Hold a pole or plumb bob against the vehicle at the widest point on one side, parallel to the side of the
    vehicle, and mark that point on the ground.
  • Similarly, mark the widest point on the other side of the vehicle. A line between the two points should be
    perpendicular to the centerline of the vehicle.
  • Measure the distance between the two points using either the telescopic pole or a tape held taut along
    the ground.

MEASURING LENGTH

If it seems the length of the vehicle or load is over the permitted limit, the assessment of its length must meet a standard of accuracy. Any method of assessing length must avoid tape sag as a potential source of error, e.g. by measuring along the ground or along the rail. Common methods for measuring length are described below.

Wheels aligned in a substantially straight line

By line of sight, or using a plumb bob or measuring pole if necessary, identify the extreme front point of the
vehicle. Mark this point on the ground and extend a straight line from there past the side of the vehicle. As far as practical, this line should be perpendicular to the centerline of the vehicle.

  • Similarly, mark the extreme rear point of the vehicle and extend a line from there to the side of the vehicle.
  • Measure the distance between the front and rear lines using a tape held taut along the ground.

Vehicle at an angle, extended lines method

  • On the ground mark lines to the side of the vehicle at the extreme front and rear of the vehicle. As far as
    practical, the extreme front line should be perpendicular to the centerline of the prime mover and the
    extreme rear line should be perpendicular to the centerline of the last component in the combination.
  • Measure the distance from the extreme front line to the extreme rear line along the short side of the vehicle. Measure the distance from the extreme front line to the extreme rear line along the long side of the vehicle.
  • Add the measured length of the short side and the measured length of the long side then divide the result
    by two to determine the overall measured length of the combination.

MEASURING GROUND CLEARANCE TO DETERMINE MAXIMUM ALLOWABLE GRADE CROSSING

The officer must verify the ground clearance is as stated in the permit. The ground clearance of the transport
vehicle must be sufficient to clear the maximum expected railroad grade crossing for the entire route. The
maximum expected railroad grade crossings for the entire route must be stated in the route survey.

CAUTION: Pay particular attention to all railroad crossings enroute. The danger of the vehicle becoming wedged on any railroad crossing always exists.

MEASURING WHEEL BASE TO DETERMINE MINIMUM TURN RADIUS AND MAXIMUM GRADE CROSSING

The officer must measure the wheel base to verify it is as stated in the permit. The wheel base of the vehicle will determine the minimum turn radius and the maximum grade crossing for the route.

C. Review the route plan and ensure copies are distributed to all participants.

The coordinating officer should be familiar with the route and have driven it within the last two weeks. The route plan should be analyzed for potential traffic flow issues, bridges, necessary enroute assistance, etc. The route plan should be shared with transportation authorities to ensure road clearances (e.g., construction zones, road closures, etc.). In addition, enough copies of the route plan should be made for all law enforcement escorts.

D. Determine the number of law enforcement escort vehicles needed based on the permit and
jurisdictional requirements.

The coordinating officer should make escort assignments for law enforcement escorts and distribute to them copies of the permit, route plan and measurement verifications.

E. Ensure a list of contacts has been compiled (i.e., power companies, utility companies, railroad companies, tow truck companies, etc.) to accompany the escort and is distributed to all participants.

States should publish a concise directory driven by the geography of the state. This directory should include at a minimum:

  • Local power companies
  • Telephone companies
  • Transmission line companies
  • Municipal Department of Public Works
  • Railroad companies
  • Emergency responders (police, hazmat, fire, rescue, EMS, etc.)
  • Cable companies
  • Tow truck companies

This directory should be available to all law enforcement escorts. Law enforcement escorts should identify the
contact information relevant to the route before departure.

F. Ensure a list of contact phone numbers for municipalities along the route has been compiled to
call when appropriate and is distributed to all participants.

As mentioned above, states should publish a concise directory driven by the geography of the state. Using this
directory or other resources, pilot car escorts should compile a list of telephone contacts and municipalities along the route.

G. Ensure a reliable means of communications is available.

It is the responsibility of all law enforcement escorts to ensure a reliable means of communication exists for the
duration of the movement.

H. Ensure a plan for enroute assistance is established as called for in the permit.

Enroute assistance may be articulated in the permit. The law enforcement escort should coordinate with the pilot car escort to plan for enroute assistance that is articulated in the permit.

I. Ensure a contingency plan has been developed that includes safe stopping places and 24 hour
emergency contact numbers.

The contingency plan should address at a minimum:

  • Vehicle breakdowns
  • Safe stopping spots
  • Inclement weather
  • 24-hour contact number for carrier
  • Illness of team member
  • Back-up and reserve vehicles and drivers
  • Highway conditions
  • Off-route contingency

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