Cover Image

Not for Sale



View/Hide Left Panel
Click for next page ( 115


The National Academies | 500 Fifth St. N.W. | Washington, D.C. 20001
Copyright © National Academy of Sciences. All rights reserved.
Terms of Use and Privacy Statement



Below are the first 10 and last 10 pages of uncorrected machine-read text (when available) of this chapter, followed by the top 30 algorithmically extracted key phrases from the chapter as a whole.
Intended to provide our own search engines and external engines with highly rich, chapter-representative searchable text on the opening pages of each chapter. Because it is UNCORRECTED material, please consider the following text as a useful but insufficient proxy for the authoritative book pages.

Do not use for reproduction, copying, pasting, or reading; exclusively for search engines.

OCR for page 114
114 APPENDIX N Lane Reductions ARIZONA before the end of the full-width lane where a painted taper begins (the actual pavement taper begins 120 to 910 ft fur- The lane line markings should be discontinued one-quarter ther downstream based on the speed and lateral offset), and of the distance between the Lane Ends sign and the point at the point where the broken lane line terminates. where the transition taper begins. Lane-reduction arrows are not shown. GEORGIA ARKANSAS The broken lane line ends at a specified distance from the end of the full-width lane based on the posted speed limit (350 ft The lane line markings are discontinued 525 ft from the point for 55 mph, 275 ft for 45 mph, and 200 ft for 35 mph). Lane- where the transition taper begins. (It is not clear if this is a reduction arrows are not shown. statewide standard or a project-specific dimension.) Lane- reduction arrows are not shown. IDAHO CALIFORNIA The broken lane line ends 200 ft from the end of the full- width lane. The use of lane-reduction arrows is optional. If The broken lane line ends at 0.75D from the end of the full- used, three lane-reduction arrows should be used with the top width lane. (D is the advance placement distance in feet for of the arrows positioned as follows: at the end of the full- Lane Ends warning signs per the MUTCD.) width lane, 200 ft from the end of the full-width lane, and 400 ft from the end of the full-width lane. Three lane-reduction arrows are used with the top of the arrows positioned as follows: at the end of the full-width lane, 200 ft from the end of the full-width lane, and 400 ft INDIANA from the end of the full-width lane. The broken lane line ends 375 ft from the end of the full- width lane. Lane-reduction arrows are not shown. COLORADO The broken lane line ends at 0.75D from the end of the full- IOWA width lane. (D is the distance in feet from the W4-2 sign to the end of the full-width lane.) Lane-reduction arrows are not The broken lane line ends at a specified distance from the shown. end of the full-width lane based on speed (565 ft for 55 mph, 415 ft for 45 mph, 300 ft for 35 mph, and 190 ft for 25 mph). Lane-reduction arrows are not shown. DELAWARE The broken lane line ends at 0.75D from the end of the full- KENTUCKY width lane. (D is the distance in feet from the W4-2 sign to the end of the full-width lane.) Lane-reduction arrows are not The broken lane line ends at 0.75D from the end of the full- shown. width lane. (D is the advance placement distance in feet for warning signs using Condition A in Table 2C-4 of MUTCD.) FLORIDA Three lane-reduction arrows are used with the top of the arrows positioned as follows: at 0.75D from the end of the The broken lane line ends at 0.75D from the end of the full- full-width lane, at D from the end of the full-width lane, and width lane. (D is the advance placement distance in feet for at D + 250 ft from the end of the full-width lane. a W9-2 warning sign and varies from 325 to 700 ft over a speed range of 30 to 55 mph.) LOUISIANA Two lane-reduction arrows, each with a MERGE pave- ment message placed just below the bottom of the arrow, are The broken lane line ends at 0.75D from the end of the full- used with the top of the arrows positioned as follows: just width lane. (D is the distance in feet from the W4-2 sign to

OCR for page 114
115 the end of the full-width lane.) Lane-reduction arrows are not line and the other is placed 100 ft before the end of the bro- shown. ken lane line. The lane-reduction arrows are the same shape as the lane use arrows used in straight-through lanes and are positioned at a 30 angle from the lane line. MARYLAND The broken lane line ends at a specified distance from the end NEVADA of the full-width lane based on speed (1,275 ft for 65 mph, 1,165 ft for 60 mph, 1,050 ft for 55 mph, 940 ft for 50 mph, The broken lane line ends at 0.75D from the end of the full- and 825 ft for 45 mph). A 10-in.-wide dotted line (3-ft seg- width lane. (D is the advance placement distance in feet for ments with 9-ft gaps) is provided from the end of the broken warning signs.) lane line to the end of the full-width lane. A lane-reduction arrow is positioned such that the bottom of the arrow is Three lane-reduction arrows are used with the top of the lined up with the beginning of the 10-in.-wide dotted line. arrows positioned as follows: at the end of the full-width Two additional lane-reduction arrows are placed in the lane, lane, at 0.25D from the end of the full-width lane, and at 0.5D one in either direction from the lane-reduction arrow that is from the end of the full-width lane. lined up with the beginning of the 10-in.-wide dotted line. These additional arrows are placed at a distance (measured NEW YORK from the bottom of one arrow to the bottom of the next arrow) that is based on speed (850 ft for 65 mph, 775 ft for The broken lane line ends 100 ft from the end of the full- 60 mph, 700 ft for 55 mph, 625 ft for 50 mph, and 550 ft for width lane. Lane-reduction arrows are not shown. 45 mph). NORTH CAROLINA MASSACHUSETTS The broken lane line ends at 0.75D from the end of the full- The broken lane line ends 565 ft (shown as 170 m) from the width lane. (D is the advance placement distance in feet for end of the full-width lane. Lane-reduction arrows are not warning signs based on the posted or 85th percentile speed shown. and ranges from 175 ft for 20 mph to 850 ft for 65 mph. The values of D are given on Sheet 3 of 3 of Standard 1205.06 in MICHIGAN North Carolina's Roadway Standard Drawings.) The broken lane line ends at a specified distance from the end A 4-in. to 6-in.-wide dotted line (2-ft segments with 13-ft of the full-width lane. The distance in feet is calculated using gaps) is placed from the end of the broken lane line to the the formula "15(S - 10) + 25," where S is the higher of the downstream end of the lane reduction taper. posted or 85th percentile speed. Five lane-reduction arrows are used with the top of the Lane-reduction arrows and MERGE messages may also arrows positioned as follows: at the end of the full-width be used. If used, two lane-reduction arrows and MERGE lane, at 100 ft from the end of the full-width lane, at 200 ft messages are used with the top of the arrows positioned as from the end of the full-width lane, at 500 ft from the end of follows: at D from the end of the full-width lane and at 2D the full-width lane, and at 800 ft from the end of the full- from the end of the full-width lane. width lane. MINNESOTA NORTH DAKOTA The broken lane line ends 200 ft from the end of the full- The broken lane line ends at 0.75D from the end of the full- width lane. Lane-reduction arrows are not shown. width lane. (D is the advance placement distance in feet for warning signs.) Lane-reduction arrows are not shown. MISSISSIPPI OREGON The broken lane line ends at an unspecified distance from the end of the full-width lane. A 6-in.-wide dotted line (2-ft seg- The broken lane line ends at 0.75D from the end of the full- ments with 12-ft gaps) is provided from the end of the bro- width lane. (D is the advance placement distance in feet for ken lane line to the end of the full-width lane. Two lane- warning signs and varies from 175 to 850 ft over a posted or reduction arrows are placed in the lane. One lane-reduction 85th percentile speed range of 20 to 65 mph as shown in a arrow is placed at the halfway point of the 6 in.-wide dotted table.)

OCR for page 114
116 Lane-reduction arrows are optional for speeds greater than the end of the full-width lane.) Lane-reduction arrows are not 45 mph and are generally not used for speeds of 45 mph or shown. less. If used, a minimum of two lane-reduction arrows must be used with the top of the arrow nearest to the end of the lane typically placed 500 ft from the end of the full-width lane. CHARLOTTE, NC Additional lane-reduction arrows are placed upstream with The broken lane line ends at the end of the full-width lane. the spacing between the bottom of the downstream arrow and the top of the upstream arrow being 200 ft. Four lane-reduction arrows are used with the top of the arrows positioned as follows: 25 ft downstream from the end PENNSYLVANIA of the full-width lane, at the end of the full-width lane, at 50 ft upstream from the end of the full-width lane, and at 100 ft The broken lane line ends at D from the end of the full-width upstream from the end of the full-width lane. lane. (D is the advance placement distance in feet for warn- ing signs using Condition A in Table 2C-4 of MUTCD.) LOS ANGELES, CA Three lane-reduction arrows are used with the center of The broken lane line ends at the end of the full-width lane. the arrow nearest to the end of the lane placed D from the end of the full-width lane. At least two additional lane-reduction Three lane-reduction arrows are used with the arrows posi- arrows are placed upstream of the arrow nearest to the end of tioned as follows: at the end of the full-width lane, at 200 ft the lane. The distance from the center of one arrow to the upstream from the end of the full-width lane, and at 400 ft center of the next arrow is 300 ft on conventional roadways upstream from the end of the full-width lane. and 600 ft on expressways and freeways. TUCSON/PIMA COUNTY, AZ TENNESSEE The broken lane line ends at a specified distance from the end The broken lane line ends at 0.75D from the end of the full- of the full-width lane based on the posted speed limit. The width lane. (D is the distance in feet from the W4-2 sign to distance is shown in a chart and ranges from 245 ft at 30 mph the end of the full-width lane.) Lane-reduction arrows are not to 475 ft at 50 mph. shown. Three lane-reduction arrows are used with the arrow far- UTAH thest upstream positioned with its top a distance D from the end of the full-width lane. The distance D in feet is calcu- The broken lane line ends at 0.75D from the end of the full- lated using the formula "15(S - 25) + 250," where S is the width lane. (D is the distance in feet from the W4-2 sign to posted speed in mph. Two additional lane-reduction arrows the end of the full-width lane.) Lane-reduction arrows are not are placed downstream from this arrow at 40-ft intervals for shown. speed limits of 30 mph or less, 80-ft intervals for 35 or 40 mph speed limits, and 120-ft intervals for speed limits of 45 mph or more. VERMONT No standards were found for: The broken lane line ends 550 ft from the end of the full- width lane. Lane-reduction arrows are not shown. Alabama Ohio Alaska Oklahoma Connecticut Rhode Island WYOMING Hawaii South Carolina Illinois South Dakota The broken lane line ends at 0.5D from the end of the full- Kansas Texas width lane. (D is the distance in feet from the W4-2 sign to Maine Virginia the end of the full-width lane.) Lane-reduction arrows are not Missouri Washington shown. Montana West Virginia Nebraska Wisconsin New Hampshire District of Columbia PUERTO RICO New Jersey New York, NY New Mexico The broken lane line ends at 0.75D from the end of the full- width lane. (D is the distance in feet from the W4-2 sign to