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Figure 3B-13. Examples of Markings for Obstructions in the Roadway
(Sheet 1 of 2)
This figure illustrates three examples of markings for obstructions
in the roadway. The figure is composed of two sheets.
The figure shows three vertical roadways, examples (a), (b), and
(c). Each example shows a black "x" inscribed in a white
square, denoting an obstruction, in the middle of a parallelogram-shaped
island formed by tapered solid lines on each side of the obstruction.
- Sheet 1 of the figure shows two vertical highways, examples
(a) and (b). Notes state "For speeds 70 km/h (45 mph) or
more L = 0.62 WS (L = WS). For speeds less than 70 km/h (45 mph)
L = WS2/155 (L = WS2/60). S = posted, 85th percentile, or statutory
speed in km/h (mph). W = offset distance in meters (ft). Minimum
length of L = 30 m (100 ft) in urban areas and 60 m (200 ft) in
rural areas. Length 'L' should be extended as required by sight
distance conditions."
A legend shows a black arrow indicating the direction of travel
in the lanes, and a black "x" inscribed in a square denoting
an obstruction.
- The first example is labeled "a - Center of two-lane
road." It shows an obstruction in an island formed by diagonal
solid yellow lines in the center of a two-lane road. Arrows show
that the direction of travel is one lane in each direction. Starting
from the bottom of the illustration, a solid double yellow line
separates the opposing lanes and then continues as it approaches
the obstruction. Then it separates into two tapering solid double
yellow lines, one solid double yellow line on each side of the
obstruction. Beyond the obstruction, the two solid double yellow
lines taper back to merge into one solid double yellow line at
the center of the roadway. The one solid double yellow line then
continues along the center of the road as it approaches the top
of the illustration. Several dimensions are shown on the figure.
"W" is shown as the offset from the normal center of
the roadway to the outside edge of the solid double yellow line
immediately opposite the obstruction. That outside edge of the
solid double yellow line is shown as 0.3 to 0.6 m (1 to 2 ft)
from the edge of the obstruction. "L" is shown as the
longitudinal distance along the roadway for the taper of the solid
double yellow line(s) from the normal center of the roadway to
the greatest width of the channelizing island at the obstruction.
The dimension of the solid double yellow line on either side of
the channelizing island is shown as "2L." A series of
parallel diagonal yellow lines, running from top right to bottom
left at a 45-degree angle, are shown filling the parallelogram-shaped
island between the two solid double yellow lines.
- The second example is labeled "b - Center of four-lane
road." It shows an obstruction in an island formed by diagonal
solid yellow lines in the center of a four-lane road. Arrows show
that the direction of travel is two lanes in each direction. A
broken white line separates the through lanes from each other.
Starting from the bottom of the illustration, a solid double yellow
line separates the opposing lanes and then continues as it approaches
the obstruction. Then it separates into two tapering solid double
yellow lines, one solid double yellow line on each side of the
obstruction. Beyond the obstruction, the two solid double yellow
lines taper back to merge into one solid double yellow line at
the center of the roadway. The one solid double yellow line then
continues along the center of the road as it approaches the top
of the illustration. Several dimensions are shown on the figure.
"W" is shown as the offset from the normal center of
the roadway to the outside edge of the solid double yellow line
immediately opposite the obstruction. That outside edge of the
solid double yellow line is shown as 0.3 to 0.6 m (1 to 2 ft).
"L" is shown as the longitudinal distance along the
roadway for the taper of the solid double yellow line(s) from
the normal center of the roadway to the greatest width of the
channelizing island at the obstruction. A series of parallel diagonal
yellow lines, running from top right to bottom left at a 45-degree
angle, are shown filling the parallelogram-shaped island between
the two solid double yellow lines.
Continue to: Sheet 2
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to Chapter 3B
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