Chapter 5C. Warning Signs
The purpose of a warning sign is to provide advance warning to the road user of unexpected conditions on or adjacent to the roadway that might not be readily apparent.
The criteria for warning signs are contained in Chapter 2C and in other Sections of this Manual. Criteria for warning signs that are specific to low-volume roads are contained in this Chapter.
Horizontal Alignment signs (see Figure 5C-1) include turn, curve, reverse turn, reverse curve, winding road, large arrow, and chevron alignment signs.
Figure 5C-1 Horizontal Alignment and Intersection Warning Signs on Low-Volume Roads
Horizontal Alignment signs may be used where engineering judgment indicates a need to inform the road user of a change in the horizontal alignment of the roadway.
Intersection signs (see Figure 5C-1) include the crossroad, side road, T-symbol, and Y-symbol signs.
Intersection signs may be used where engineering judgment indicates a need to inform the road user in advance of an intersection.
A Stop Ahead (W3-1) sign (see Figure 5C-2) shall be used where a STOP sign is not visible for a sufficient distance to permit the road user to bring the vehicle to a stop at the STOP sign.
A Yield Ahead (W3-2) sign (see Figure 5C-2) shall be used where a YIELD sign is not visible for a sufficient distance to permit the road user to bring the vehicle to a stop, if necessary, at the YIELD sign.
Figure 5C-2 Other Warning Signs on Low-Volume Roads
Option: Word message (W3-1a and W3-2a) signs may be used as alternates to symbol signs.
The NARROW BRIDGE (W5-2) sign (see Figure 5C-2) may be used on an approach to a bridge or culvert that has a clear width less than that of the approach roadway.
A ONE LANE BRIDGE (W5-3) sign (see Figure 5C-2) should be used on low-volume two-way roadways in advance of any bridge or culvert:
- Having a clear roadway width of less than 4.9 m (16 ft); or
- Having a clear roadway width of less than 5.5 m (18 ft) when commercial vehicles constitute a high proportion of the traffic; or
- Having a clear roadway width of 5.5 m (18 ft) or less where the approach sight distance is limited on the approach to the structure.
Roadway alignment and additional warning may be provided on the approach to a bridge or culvert by the use of object markers and/or delineators.
An engineering study of vehicles and road characteristics, such as percent grade and length of grade, may be conducted to determine hill signing requirements.
The use of the Hill (W7-1) sign (see Figure 5C-2) on low-volume roads may be confined to roads where commercial or recreational vehicles are anticipated.
Word messages (W7-1a) may be used as alternates to symbols.
A PAVEMENT ENDS (W8-3) sign (see Figure 5C-2) may be used to warn road users where a paved surface changes to a gravel or earth road surface.
Vehicular Traffic signs (see Figure 5C-2) should be used to alert road users to frequent unexpected entries into the roadway by trucks, bicyclists, farm vehicles, fire trucks, and other vehicles. Such signs should be used only at locations where the road user’s sight distance is restricted or the activity would be unexpected.
Nonvehicular signs (see Figure 5C-2) may be used to alert the road user to frequent unexpected entries into the roadway by pedestrian, animal, and other crossing activities that may cause potential conflicts.
A W7-3a, W16-2, or W16-9p supplemental plaque (see Figure 5C-2), with the legend NEXT XX km (NEXT XX MILES), XX METERS (XX FEET), or AHEAD may be installed below a Vehicular Traffic or Nonvehicular sign (see Sections 2C.40 and 2C.41).
If the activity is seasonal or temporary, the sign should be removed or covered when the crossing activity does not exist.
An Advisory Speed (W13-1) plaque (see Figure 5C-1) may be mounted below a warning sign when the condition requires a reduced speed.
The DEAD END (W14-1) and NO OUTLET (W14-2) signs (see Figure 5C-2) and the DEAD END (W14-1a) and NO OUTLET (W14-2a) signs (see Figure 2C-3) plaques may be used to warn road users of a road that has no outlet or that terminates in a dead end or cul-de-sac.
If used, these signs should be placed at a location that gives drivers of large commercial or recreational vehicles an opportunity to select a different route or turn around.
A W18-1 warning sign (see Figure 5C-2) with the legend NO TRAFFIC SIGNS may be used only on unpaved, low-volume roads to advise users that no signs are installed along the distance of the road. If used, the sign may be installed at the point where road users would enter the low-volume road or where, based on engineering judgment, the road user may need this information.
A W7-3a, W16-2, or W16-9p supplemental plaque (see Figure 5C-2) with the legend NEXT XX km (NEXT XX MILES), XX METERS (XX FEET), or AHEAD may be installed below the W18-1 sign when appropriate.
Other warning signs used on low-volume roads that are not discussed in Part 5, but are in this Manual, shall conform with the criteria contained in other Parts of this Manual. Warning signs that are not specified in this Manual shall conform to the criteria in Sections 2C.02 and 2C.03.