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Incident Sign Installation Guide

Advance Placement of Guide Signs at Intersections

The distance from the first sign to the start of the incident area should be long enough to give road users enough time to respond to the conditions.

Use the following table to determine the spacing for Guide signs.

Make sure you place guide signs far enough in front of the point where road users should begin maneuvering by using the distances in table 2.

Table 2—Advance placement of guide signs at intersections.
Speed limit or prevailing approach speed
(miles per hour)
Distance from the intersection
Less than 15 25
15 to 25 100
30 to 40 100 to 200
Over 45 200 minimum
For expressways and freeways, contact the applicable State department of transportation.

Graphic showing the advanced placement of guide signs at intersections. The graphic shows a main roadway along with a road that is perpendicular to the roadway. A sign is placed at a specific distance from the intersection based off of the values in table two. The sign in the graphic reads, "INCIDENT BASE" and has an arrow showing the direction of the base.
**Obtain distance from table 2 (page 9).

Incident Management Activity at Intersections

Application Notes

Install a warning and guide sign at each approach to the intersection. The warning sign (sign 1) attracts attention. It is the most critical sign and always takes precedence over the guide sign (sign 2).

Use the FIRE TRAFFIC ENTERING ROAD warning sign to warn approaching road users that incident traffic is entering and exiting at the intersection.

Use of the advisory speed plaque is optional. Its use requires approval by the applicable State department of transportation if it is placed on State roads.

Don't use advisory speed plaques by themselves.

If enforceable or advisory speed limits are necessary, work with the appropriate road agency that has jurisdiction.

Use guide signs at critical intersections to direct incident management traffic to destinations such as:

  • Incident bases
  • Helibases
  • Staging areas
  • Helicopter bucket dip sites
  • Washing stations

When several incidents are in the same area, a nameplate may help people locate the right incident. The name of the incident should be on a separate sign mounted on top of the guide sign.

Photo of two signs along a roadway. The first sign reads, "FIRE TRAFFIC ENTERING ROAD 35 M.P.H." and the second sign is unreadable.

Graphic of a main roadway and a subroadway intersection with the appropriate signs used for incident management activity at an intersection.
Incident Management Activity at Intersections
*Obtain distance from table 1 (page8).
**Obtain distance from table 2 (page 9).
(Click here for long description)