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39 acceleration lane is used, but are used within the paved gores of from the downstream end of the gore to the downstream end entrance ramps when a tapered acceleration lane is used. of the taper for the acceleration lane. Three through arrows at a 45 angle are placed at 100-ft intervals ending at the downstream end of the acceleration lane. Width of Chevrons Within Paved Gore (7 agencies) The design standards for the seven agencies that specify a The design standards for Tennessee show that for tapered width for the chevrons (at a forward angle of 45) that are acceleration lanes a 6-in.-wide dotted line (2-ft segments placed within the paved gores of entrance ramps use the fol- with 4-ft gaps) is placed along the right-hand side of the adja- lowing widths: cent mainline lane from the downstream end of the gore to the downstream end of the entrance ramp. OK--8 in. IN--12 in. when the posted speed limit is 45 mph or less The design standards for West Virginia show for tapered and 24 in. when the posted speed limit is more than acceleration lanes a 4-in.-wide dotted line (2-ft segments 45 mph with 13-ft gaps) being placed along the right-hand side of the TN, PR--12 in. adjacent mainline lane from the downstream end of the gore MD--16 in. to the downstream end of the taper for the acceleration lane. FL--18 in. VA--24 in. EXIT RAMP GORES Width of Channelizing Lines (44 agencies) Spacing of Chevrons Within Paved Gore (7 agencies) The following widths are explicitly specified in the design The design standards for the seven agencies that specify the standards for the channelizing lines associated with exit spacing (measured along the edge line of the mainline road- ramps: way) for the chevrons that are placed within the paved gores WV--6 to 8 in. of entrance ramps use the following spacings: CA, CO, CT, FL, HI, IL, IN, IA, KS, LA, MA, MN, MO, PR--7 ft (shown as 2.0 m) MT, ND, OK, OR, PA, TN, TX, UT, VA, WA, WI, VA--8 ft WY, PR, NYC--8 in. OK--10 ft AL, NC, OH--8 in. or 12 in. IN--20 ft when the posted speed limit is 45 mph or less and SC--8 in. for primary and secondary highways and 12 in. 40 ft when the posted speed limit is more than 45 mph for expressways and freeways FL--20 ft GA, MD--10 in. TN--20 ft (until the width of the gore becomes 6 ft) AZ, DE, MI, MS, NE, NV, NH, NY, RI, VT--12 in. MD--50 ft for blunt angle gores and up to 100 ft for sharp angle gores. Use Versus Non-Use of Channelizing Line on Right-Hand Side of Mainline Roadway (44 agencies) Other Considerations for Entrance Ramps (6 agencies) The design standards consistently show that the use of a channelizing line on the right-hand side of the mainline road- The design standards for Maryland show that the last chevron way is required for exit ramps. stripe is placed 50 ft upstream from the point where the gore width becomes 1 ft wide. Upstream End of Channelizing Lines for Exit The design standards for Massachusetts do not show Ramps with Tapered Deceleration Lanes pavement markings within the paved portion of the gore, but (44 agencies) "rubble block" is shown as an option in this area unless travel is sometimes permitted in the breakdown lane (shoulder) of The design standards consistently show that the upstream the mainline roadway. end of channelizing lines for exit ramps with tapered decel- eration lanes to be the point where the full width of the exit The design standards for Michigan show that at the down- ramp first becomes available. stream end of the gore the two 12-in.-wide channelizing lines are side-by-side, thus resulting in a 24-in.-wide line. Downstream End of Channelizing Line on Left-Hand Side of Exit Ramp (43 agencies) The design standards for North Carolina show a 4- to 6-in.-wide dotted line (2-ft segments with 13-ft gaps) being The following points (measured downstream from the down- placed along the right-hand side of the adjacent mainline lane stream end of the paved gore) are explicitly specified in the

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40 design standards for the downstream end of the channelizing KS--at the point where the extra roadway paving on the line on the left-hand side of the entrance ramp: right of the right edge line of the mainline roadway ends (diagonal lines that are 12 in. wide at a 30 angle AL, CA, FL, GA, IN, IA, MA, MI, MN, MO, MT, NV, at 40-ft spacing are placed in the extra roadway paving) NY, NC, OH, OR, PA, SC, UT, VT, VA, WA, WY, MS--at the point well beyond the downstream end of the PR--0 ft gore where the portion of the shoulder that is paved KS--0 ft for parallel deceleration lanes and an unspecified with mainline roadway paving (as opposed to shoulder distance downstream for tapered deceleration lanes thickness paving) becomes only 6 ft wide NH--5 ft NE, SC, NYC--unspecified distance downstream. CT--20 ft HI--40 ft ND--40 ft for parallel deceleration lanes and 240 ft from Use Versus Non-Use of Chevrons or Diagonal Lines Within the Paved Gore (45 agencies) the upstream end of the paved gore for tapered decel- eration lanes The design standards for 11 agencies (AZ, FL, HI, IN, KS, LA, AZ, DE, IL, MD, TN, WI--50 ft OK, RI, TN, PR, and NYC) show that the use of chevrons TX--at the downstream end of the paved shoulder por- within the paved gores of exit ramps is required. The design tion of the gore standards for Indiana state that when ramp volumes are low, CO--at the location of the Exit Gore sign diagonal lines may be used instead of chevrons. The design WV--25 ft downstream from the location of the Exit standards for Tennessee note that if the gore area is so short Gore sign that at least five chevrons cannot be placed within the gore the LA--at the point where the shoulder returns to normal chevrons are omitted from the gore area. width OK--at the point where the paved shoulder begins The design standards for New York State show that the MS--at the point where the curvature on the ramp changes use of chevrons is required within the paved gores of exit NE, NYC--unspecified distance downstream. ramps at major exits, and the use of diagonal lines is required within the paved gores of exit ramps at minor exits. Downstream End of Channelizing Line on Right-Hand Side of Mainline Roadway The design standards for Texas and West Virginia show (43 agencies) that the use of diagonal lines within the paved gores of exit ramps is required. The following points (measured downstream from the down- stream end of the paved gore) are explicitly specified in the The design standards for Massachusetts show that the use design standards for the downstream end of the channelizing of diagonal lines within the paved gores of exit ramps is line on the right-hand side of the mainline roadway: required unless travel is sometimes permitted in the break- down lane (shoulder) of the mainline roadway. AL, CA, FL, GA, IN, IA, MA, MI, MN, MO, MT, NV, NY, NC, OK, OR, UT, VT, WA, WY, PR--0 ft The design standards for five agencies (CO, CT, KY, MD, ND--0 ft for parallel deceleration lanes and 200 ft from the and VA) state or show that the use of chevrons within the upstream end of the paved gore for tapered deceleration paved gores of exit ramps is optional. lanes NH--5 ft The design standards for four agencies (IL, OH, VT, and CT--20 ft WI) state or show that the use of diagonal lines within the HI--40 ft paved gores of exit ramps is optional. DE--less than 50 ft (the point on the right edge line where a perpendicular line would line up with the downstream The design standards for Pennsylvania state or show that end of the gore striping on the ramp) the use of chevrons or diagonal lines within the paved gores AZ, IL, MD, PA, TN, WI--50 ft of exit ramps is optional. VA--150 ft TX--at the downstream end of the paved shoulder portion The design standards for Oregon state or show that of the gore chevrons or diagonal lines are not used within the paved CO--at the location of the Exit Gore sign gores of exit ramps with parallel deceleration lanes, but the WV--25 ft downstream from the location of the Exit use of chevrons or diagonal lines within the paved gores of Gore sign exit ramps with tapered deceleration lanes is optional. OH--at the point where the paved shoulder ends LA--at the point where the shoulder returns to normal The design standards for 18 agencies (CA, DE, GA, IA, width MI, MN, MS, MO, MT, NE, NV, NH, NC, ND, SC, UT,

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41 WA, and WY) state or show that chevrons or diagonal lines IN--20 ft when the posted speed limit is 45 mph or less and are not used within the paved gores of exit ramps. 40 ft when the posted speed limit is more than 45 mph CO--25 ft (starting at the point where the gore becomes The design standards for Alabama show that chevrons are 6 ft wide) not used within the paved gores of exit ramps unless a recov- AZ, KS--40 ft ery area or a parallel recovery lane is provided. MD--50 ft for blunt angle gores and up to 100 ft for sharp angle gores. Width of Chevrons or Diagonal Lines Within the Paved Gore (25 agencies) Use Versus Non-Use of Dotted Line in Departure Area of Tapered Deceleration Lane (41 agencies) The design standards for the 25 agencies that specify a width for the chevrons (at a forward angle of 45) or diagonal lines The design standards for 20 agencies (AL, CO, CT, GA, HI, (at a forward angle of 45 from the right edge line of the main- IN, IA, KS, MI, NH, NC, ND, OH, OK, TN, TX, UT, VT, line lane unless otherwise stated--they do not intersect the left WV, and WI) show that the use of a dotted line to extend the edge line of the ramp at a 45 forward angle) that are placed right edge line of the mainline roadway to the upstream end within the paved gores of exit ramps use the following widths: of the paved gore of exit ramps with tapered deceleration lanes is required. CO, OK--8 in. AZ, HI, IL, KS, OR, RI, TN, VT, PR--12 in. The design standards for New York City show that the use MA--12 in. at a 3-to-1 slope forward angle from the right of a dotted line to extend the right edge line of the mainline edge line of the mainline lane (they do not intersect the roadway to the upstream end of the paved gore of exit ramps left edge line of the ramp at a forward angle) with tapered deceleration lanes is typically used. IN--12 in. when the posted speed limit is 45 mph or less and 24 in. when the posted speed limit is more than 45 The design standards for nine agencies (AZ, IL, MS, MT, mph NY, OR, PA, WY, and PR) show that the use of a dotted line MD, NYC--16 in. to extend the right edge line of the mainline roadway to the FL--18 in. upstream end of the paved gore of exit ramps with tapered TX--typically 24 in., but no less than 12 in. deceleration lanes is optional. AL, LA, NY, OH, PA, VA, WV, WI--24 in. The design standards for 11 agencies (CA, FL, LA, MD, MN, MO, NE, NV, SC, VA, and WA) state or show that dot- Spacing of Chevrons or Diagonal Lines ted lines are not used to extend the right edge line of the Within Paved Gore (23 agencies) mainline roadway to the upstream end of the paved gore of exit ramps with tapered deceleration lanes. The design standards for the 23 agencies that specify the spacing (measured along the edge line of the mainline road- way) for the chevrons or diagonal lines that are placed within Width of Dotted Line in Departure Area of Tapered the paved gores of exit ramps use the following spacings: Deceleration Lane (28 agencies) VT--7 ft The following widths are used for the dotted line in the PR--7 ft (shown as 2.0 m) departure area of exit ramps with tapered deceleration lanes: VA--8 ft WV--8 to 12 ft AL, CO, HI, IL, IN, IA, MT, ND, OK, TX, UT, VT, WV, WI--8 to 25 ft WI, WY--4 in. OK--10 ft NC, OH--4 to 6 in. IL--10 to 20 ft GA--5 in. NY--11 ft (shown as 3.3 m) AZ, CT, KS, MI, MS, NH, NY, TN--6 in. LA--12 ft for posted mainline speed limits of 45 mph or PA, NYC--8 in. less, 18 ft for 50 or 55 mph, and 24 ft for 65 mph OH--12 ft for the first 48 ft, 24 ft for the next 48 ft, and Type of Dotted Line in Departure Area of Tapered 48 ft thereafter Deceleration Lane (28 agencies) AL--15 ft in urban areas and 25 ft in rural areas PA--16 ft The following patterns are used for the dotted line in the MA--16 ft (shown as 5 m) departure area of exit ramps with tapered deceleration lanes: FL, HI, RI, TX--20 ft TN--20 ft (starting at the point where the gore becomes AL, AZ, CO, IA, KS, MT, OH, PA, TN, TX, VT, NYC-- 6 ft wide) 2-ft segments with 4-ft gaps

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42 GA, ND, OR, UT, WY--2-ft segments with 6-ft gaps lane's entire length and within the left shoulder of the ramp HI, IN--2-ft segments with 8-ft gaps for a distance of 80 ft beyond the point where the paved por- CT, NH, NY--2-ft segments with 10-ft gaps tion of the gore ends. For exit ramps with a recovery area, MS--2-ft segments with 12-ft gaps diagonal 12-in.-wide lines at 20-ft intervals in urban areas NC, WV--2-ft segments with 13-ft gaps and 30- to 40-ft intervals in rural areas are used within the OK, WI--3-ft segments with 12-ft gaps right shoulder of the mainline roadway for a distance of at MI--5-ft segments with 20-ft gaps. least 320 ft beyond the point where the paved portion of the gore ends and within the left shoulder of the ramp for a dis- The design standards for Ohio show that a 4- to 6-in.-wide tance of 80 ft beyond the point where the paved portion of broken lane line (10-ft segments with 30-ft gaps) is placed the gore ends. from the point where a full lane width first becomes available to the upstream end of the gore. An optional 4- to 6-in.-wide The design standards for Florida show that diagonal 18-in.- dotted line (2-ft segments with 4-ft gaps) may be placed wide cross-hatching is placed beyond the gore on the right along the right-hand side of the adjacent mainline lane from shoulder of the mainline roadway until the shoulder width the upstream end of the ramp to the upstream end of the bro- returns to its normal width. ken lane line. The design standards for Maryland show that the first The design standards for Oklahoma show that a 4-in.- chevron stripe is placed 50 ft downstream from the point wide dotted line (3-ft segments with 12-ft gaps) followed by where the gore width becomes 1 ft. a 4-in.-wide broken lane line is placed along the right-hand side of the adjacent mainline lane from the upstream end of The design standards for Michigan show that at the up- the exit ramp to the upstream end of the gore. stream end of the gore, the two 12-in.-wide channelizing lines are side-by-side, thus resulting in a 24-in.-wide line. Other Considerations for Exit Ramps (5 agencies) The design standards for Washington State show that The design standards for Alabama show that for exit ramps raised pavement markers forming diagonal lines that point at with a tapered deceleration lane and a parallel recovery lane, a 45 forward angle from the right edge line of the mainline diagonal 12-in.-wide lines at 20-ft intervals in urban areas lane (they do not intersect the left edge line of the ramp at a and 30- to 40-ft intervals in rural areas are used within the 45 forward angle) may be placed within the paved portion right shoulder of the parallel recovery lane for the recovery of the gore to increase visibility.