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117 APPENDIX O Channelizing Islands, Painted Medians, Paved Shoulders, and Approaches to Obstructions ALASKA 18 in. wide. The spacing of diagonal lines on paved shoul- ders and in painted medians can vary from 10 to 40 ft based No diagonal lines are used in painted medians or on paved on the posted speed limit. shoulders, but 18-in. diagonal lines at 12-ft. spacing are placed in the median on approaches to obstructions. The edge lines surrounding right-turn channelizing islands are 8-in.-wide solid lines. Chevrons or cross-hatching lines Right-turn channelizing islands are outlined by 8-in. lines, that are 18 in. wide and are spaced at 10-ft intervals are used and 18-in. white chevrons at 7-ft. spacing are used within throughout the paved portion of the right-turn island. right-turn channelizing islands. GEORGIA ARIZONA Diagonal lines in painted medians are 24 in. wide at 15-ft No diagonal lines are used in painted medians. spacing. ARKANSAS Diagonal lines on paved shoulders are 24 in. wide at 15- to 50-ft spacing. Right-turn channelizing islands are outlined by 8-in. lines. No diagonal lines are used. Chevron markings in channelizing islands are 24 in. wide at 15-ft spacing. The solid lines forming the island are 8 in. CALIFORNIA wide. The diagonal lines or chevron markings are normally 12 in. The spacing of 12-in.-wide diagonal lines or chevrons on wide. The spacing between diagonal lines or chevron mark- approaches to obstacles is 5 ft. ings may vary from 12 in. in a pedestrian crosswalk to 200 ft for vehicular traffic. HAWAII COLORADO Diagonal lines in painted medians are 12 in. wide at a typi- cal spacing of 20 ft. Diagonal lines or chevron markings are 8 in. wide at 25-ft spacing. The spacing of diagonal lines on paved shoulders Diagonal lines on paved shoulders are 12 in. wide at a typ- can vary from 20 ft to 100 ft. ical spacing of 40 ft. Diagonal lines on paved shoulders and in painted medians Chevron markings in channelizing islands are 12 in. wide are optional. at a typical spacing of 20 ft. The solid lines forming the island are 8 in. wide. Painted right-turn channelizing islands are formed with 8-in.-wide solid lines with no markings within the island. IDAHO Raised right-turn channelizing islands are marked by 8-in.- Diagonal or chevron markings should not be placed as a stan- wide solid lines on both sides of the gore area leading up to dard practice because of the questionable benefits and high the island, and along the left edge line of the right-turn lane exposure of paint crews to traffic. Exceptions should be lim- from the point where the island ends to the point where the ited to those locations where the additional emphasis is clearly line intersects the right edge line of the intersecting roadway. needed and then only for those with widths of 10 ft or more. The rest of the raised island is surrounded by 4-in.-wide edge lines. There are no markings between the raised island and ILLINOIS the 4-in.-wide edge lines or 8-in.-wide solid lines. The spacing of diagonal lines used on paved shoulders and in FLORIDA painted medians between intersections should be 50 ft when the speed limit is less than 30 mph, 75 ft when the speed limit Diagonal lines are optional on paved shoulders. Diagonal is 30 to 45 mph, and 150 ft when the speed limit is more than lines are required in painted medians. The diagonal lines are 45 mph.

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118 The spacing of diagonal lines used in painted medians near wide when the speed is more than 45 mph and that are spaced intersections and in pavement width transition markings should at 20-ft intervals are used throughout the paved portion of the be 15 ft when the speed limit is less than 30 mph, 20 ft when right-turn island. the speed limit is 30 to 45 mph, and 30 ft when the speed limit is more than 45 mph. Solid 12-in.-wide lane lines are used to form a painted island on approaches to raised islands or other obstacles The spacing of diagonal lines used on approaches to (where traffic flows in the same direction on either side of the obstructions and in islands for channelized turns should be island). Chevrons that are 6 in. wide when the speed is 45 mph 10 ft when the speed limit is less than 30 mph, 15 ft when the or less or 12 in. wide when the speed is more than 45 mph are speed limit is 30 to 45 mph, and 20 ft when the speed limit is spaced at 20-ft intervals within the painted island. more than 45 mph. Diagonal lines are optional in painted medians. If used, In all of these cases, if the recommended spacing does not the diagonal lines are 6 in. wide when the posted speed limit provide at least five 12-in.-wide diagonal lines in the area is 45 mph or less or 12 in. wide when the posted speed limit being marked, the spacing from the next lowest speed range is more than 45 mph. The spacing of diagonal lines on paved should be used. shoulders and in painted medians can vary from 10 to 40 ft based on the posted speed limit. INDIANA Two sets of 4-in.-wide double yellow centerlines are used to form a painted island on approaches to raised medians or When the posted speed limit is 45 mph or less, the spacing of other obstacles (where traffic flows in the opposite direction 12-in.-wide diagonal lines used in painted medians should be on either side of the island). Diagonal lines that are 6 in. 20 ft. When the posted speed limit is more than 45 mph, the wide when the posted speed limit is 40 mph or less or 12 in. spacing of 24-in.-wide diagonal lines used in painted medi- wide when the posted speed limit is more than 40 mph are ans should be 40 ft. placed within the painted island. The spacing of the diagonal lines can vary from 10 to 40 ft based on the posted speed limit. The edge lines surrounding right-turn channelizing islands are 8-in.-wide solid lines. Diagonal lines that are 12 in. wide and are spaced at 20-ft intervals are used throughout the MINNESOTA paved portion of the right-turn island. Diagonal lines in painted medians are 24 in. wide at 20-ft spacing (measured perpendicular to the diagonal lines instead IOWA of along the lane line). For speeds less than 40 mph, the diag- onal lines may be reduced to 12 in. in width. For speeds more The spacing of 8-in.-wide diagonal lines used in painted than 40 mph, the spacing may be increased to 30 ft. medians and channelizing islands is 20 ft. If the width of the painted median becomes less than 2 ft, the median is painted solid yellow. The lines outlining the painted median or chan- MISSISSIPPI nelizing island are also 8 in. wide. Diagonal lines in painted medians are 18 in. wide at 20-ft spacing. The lines surrounding the painted median are 12-in.- KANSAS wide solid lines. Diagonal and chevron lines are 12 in. wide, are inclined at a Diagonal lines on paved shoulders are 18 in. wide at 20-ft 30 angle, and are spaced at a distance in feet equal to the spacing. speed in mph. MONTANA LOUISIANA The edge lines surrounding right-turn channelizing islands Diagonal lines in painted medians are 24 in. wide at 24-ft are 8-in.-wide solid white lines. Chevrons or cross-hatching spacing. lines are not used on the paved portion between the edge lines and the raised island. The curbs of the raised right-turn chan- MICHIGAN nelizing islands are painted yellow. The edge lines surrounding right-turn channelizing islands Diagonal lines in painted medians are 24 in. wide, are in- are 6-in.-wide solid lines. Chevrons or cross-hatching lines clined at a 30 angle, and are spaced at 25-ft (shown as 7.5-m) that are 6 in. wide when the speed is 45 mph or less or 12 in. intervals.

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119 NEBRASKA are not used on the paved portion between the edge lines and the raised island. Chevrons that are 8 in. wide at 10-ft spacing Diagonal lines in painted medians are 12 in. wide. The spac- are used in painted right-turn channelizing islands. ing of diagonal lines on painted medians is 12 ft in urban areas and 20 ft in rural areas. Diagonal lines in painted medians are 8 in. wide and are spaced at 15-ft intervals. NEW HAMPSHIRE OREGON Diagonal lines are optional on paved shoulders and in painted medians. If used, the diagonal lines are 24 in. wide. The spac- Diagonal lines are optional in painted medians. If used, the ing of diagonal lines on paved shoulders and in painted medi- diagonal lines are 12 in. wide and are placed at a 36 angle ans is 20 ft. to the lane line. The spacing of diagonal lines in painted medians is 20 ft; however, a 40-ft spacing may be used when the distance between left-turn lanes exceeds 200 ft. The diag- NEW YORK onal lines are rectangular in shape and do not connect to the Diagonal lines in painted medians are usually 24 in. wide at lane lines. The nearest points of the diagonal lines are placed 11-ft (shown as 3.3-m) spacing. However, two other patterns 4 in. from the centerline. of diagonal lines are also available to the designer. The diag- onal lines may be 8 in. wide at a 15 angle at 10-ft (shown as Chevrons or cross-hatching lines are optional in right-turn 3.0-m) spacing or may be 12 in. wide at a 20 angle at 12-ft channelizing islands. (shown as 3.6-m) spacing. The 15 and 20 angles are mea- sured from the centerline. PENNSYLVANIA Diagonal lines on paved shoulders are usually 24 in. wide Diagonal lines are used in painted medians only when re- at a maximum spacing of 100 ft. However, two other patterns quired to provide emphasis if the visibility or sight distance of diagonal lines are also available to the designer. The diag- is restricted. If used, the diagonal lines are 24 in. wide and onal lines may be 8 in. wide at a 15 angle at 10-ft (shown as are spaced at 8-ft intervals when speeds are 35 mph or less 3.0-m) spacing or may be 12 in. wide at a 20 angle at 12-ft and at 16-ft intervals when speeds are more than 35 mph. (shown as 3.6-m) spacing. The 15 and 20 angles are mea- sured from the edge line. Diagonal lines on shoulders are 24 in. wide and are spaced at intervals equal in feet to the posted speed limit in miles per NORTH CAROLINA hour. The spacing may be increased to 200 ft or more on Interstate highways. The spacing of 8-in.-wide diagonal lines or chevrons used in painted medians and channelizing islands is typically equal in The edge lines surrounding raised right-turn channelizing feet to the posted speed limit in mph. The spacing of the diag- islands are 4-in.-wide solid white lines. Chevrons or cross- onal lines can be increased to 200 ft or more on shoulders of hatching lines are not used on the paved portion between the Interstate roadways. edge lines and the raised island. OHIO RHODE ISLAND Diagonal lines and chevrons that are 24 in. wide are used on Diagonal lines and chevrons are 12 in. wide. Diagonal lines shoulders, in painted medians that are more than 6 ft wide, in painted medians are spaced at 10-ft intervals. and in islands. Diagonal lines may be used, but are typically not used if the painted median is 6 ft or less in width. The spacing of the diagonal lines or chevrons is 12-ft for the first SOUTH CAROLINA 48 ft, 24 ft for the next 48 ft, and 48 ft thereafter. If a painted Chevron markings in islands separating traffic moving in the median separates opposing directions of traffic, the 12-ft spac- same direction are 24 in. wide at 6-ft spacing. ing starts on both ends of the painted median. Diagonal lines in painted medians are 24 in. wide. The di- OKLAHOMA agonal lines begin when the median width reaches 2 ft. The first five diagonal lines are spaced at 6-ft intervals, the next The edge lines surrounding right-turn channelizing islands are four diagonal lines are spaced at 12-ft intervals, and the 8-in.-wide solid white lines. Chevrons or cross-hatching lines remaining diagonal lines are spaced at 18-ft intervals. The

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120 diagonal lines end when the median width reaches 8 ft; how- The edge lines surrounding raised right-turn channelizing ever, the length of median with diagonal lines spaced at 18-ft islands are 8-in.-wide solid white lines. Chevrons that are 8 in. intervals is not less than 72 ft or more than 500 ft. wide at 10-ft spacing are placed in the painted island area before the raised portion of the island and in the painted island area after the raised portion of the island. SOUTH DAKOTA Diagonal lines in painted medians are 24 in. wide and are typ- VERMONT ically spaced at 25-ft intervals. Diagonal lines in painted medians in the transition from two-lane highways to four-lane Diagonal lines in painted medians are 8 in. wide. Diagonal lines divided highways are 24 in. wide and are spaced at 20-ft are spaced at 7-ft intervals where speeds are low, where sight intervals. distance is less than 200 ft, and where the length of the painted median is 75 ft or less. Diagonal lines are spaced at 14-ft inter- vals where speeds are high and sight distance is 200 ft or more, TENNESSEE and where the length of the painted median is more than 75 ft. Diagonal lines and chevrons are 12 in. wide. Painted medians and islands that are 4 ft or less in width and triangular islands that have an area of less than 450 ft2 are Diagonal lines in painted medians that are at least 6 ft painted in their entirety. The edge lines surrounding triangular wide and on shoulders are spaced at 50-ft intervals when the islands that have an area of 450 ft2 or more are 48-in.-wide solid posted speed limit is 40 mph or less and 100-ft intervals when white lines, and chevrons or cross-hatching lines are not used. the posted speed limit is 45 mph or more. WEST VIRGINIA Diagonal lines and chevrons on approaches to obstruc- tions are spaced at 10-ft intervals when the posted speed limit Diagonal lines in painted medians are 12 in. wide and are is 40 mph or less and 20-ft intervals when the posted speed spaced at 12-ft intervals. limit is 45 mph or more. The edge lines surrounding painted islands are 6- to 8-in.- Diagonal lines in painted medians where a left-turn lane wide solid lines. Chevrons or diagonal lines that are 12 in. is formed by roadway widening at an intersection are spaced wide at 6-ft spacing are used in painted islands. at 10-ft intervals and start when the width of the median becomes 6 ft. WISCONSIN The edge lines surrounding right-turn channelizing islands Diagonal lines in painted medians are 12 in. wide and are that have an area of less than 400 ft2 or less are 8-in.-wide typically spaced at 25-ft intervals. Diagonal lines begin when solid white lines. Chevrons that are 12 in. wide at 10-ft spac- the painted median becomes 3 ft wide. ing are placed inside the island. The edge lines on the approaches to raised islands are 8-in.- The edge lines surrounding right-turn channelizing islands wide solid lines that extend 5 ft beyond the nose of the island. that have an area of 400 ft2 or less are 24-in.-wide solid white lines. Chevrons or cross-hatching lines are not used. WYOMING The edge lines surrounding raised right-turn channelizing The edge lines surrounding painted islands are 8-in.-wide islands are 8-in.-wide solid white lines. Diagonal lines that solid white lines. Chevrons or diagonal lines are not used in are 12 in. wide at 10-ft spacing are placed in the paved por- painted islands. tion between the edge lines and the raised island if the width of the paved portion is at least 6 ft. DISTRICT OF COLUMBIA TEXAS Diagonal lines or chevrons in painted medians, gore areas, channelizing islands, shoulders, and approaches to obstruc- Diagonal lines in painted medians are typically 24 in. wide, tions are 12 in. wide and are spaced at 5-ft intervals. but no less than 12 in. wide, and are spaced at 20-ft intervals. PUERTO RICO UTAH Diagonal lines are optional on shoulders and are 12-in. lines Diagonal lines are optional in painted medians. If used, the spaced at 33-ft intervals. Diagonal lines are not used in painted diagonal lines are 8 in. wide and are spaced at 10-ft intervals. medians.

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121 CHARLOTTE, NC 24 in. wide when the speed limit is 45 mph or more. Diag- onal lines or chevrons in painted medians or islands are Diagonal lines or chevrons on shoulders, painted medians, spaced at 20-ft intervals when the speed limit is 40 mph or and painted islands are 12 in. wide, are inclined at a 30 angle less and at 80-ft intervals when the speed limit is 45 mph from the lane line, and are spaced at 30-ft intervals. or more. NEW YORK, NY No standards were found for: Diagonal lines on shoulders are 16-in. lines spaced at unspec- Alabama Nevada ified intervals. Connecticut New Jersey Delaware New Mexico Kentucky North Dakota TUCSON/PIMA COUNTY, AZ Maine Virginia Maryland Washington Diagonal lines or chevrons in painted medians or islands Massachusetts Los Angeles, CA are 12 in. wide when the speed limit is 40 mph or less and Missouri