620.16 Measurement of Retroreflectivity by Handheld Retroreflectometers - Revision history

Hoskir: Renamed, renumbered article due to MUTCD updates (See Special Ballot)

2026-01-06T16:08:58Z

Renamed, renumbered article due to MUTCD updates (See Special Ballot)

← Older revision		Revision as of 11:08, 6 January 2026
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	[[~~image~~:620 Retroreflectivity ~~reading~~.jpg\|right\|400 px]]		[[Category:620 Pavement Marking (MUTCD Part 3)\|620.16]]
			[[File:Figure 620.16 Retroreflectivity Reading.jpg\|right\|400 px]]

	The following guidelines are based on MoDOT Test Method TM80 and ASTM D7585-10.		The following guidelines are based on MoDOT Test Method TM80 and ASTM D7585-10.
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	These guidelines are to be used by MoDOT forces when determining the quality and remaining life of MoDOT pavement markings, both existing and newly applied.		These guidelines are to be used by MoDOT forces when determining the quality and remaining life of MoDOT pavement markings, both existing and newly applied.

	==620.13.1 Scope==		==620.16.1 Scope==
	This method describes the procedure for retroreflectivity inspections of pavement markings using a handheld retroreflectometer.		This method describes the procedure for retroreflectivity inspections of pavement markings using a handheld retroreflectometer.

	===620.13.1.1 Definitions===		===620.16.1.1 Definitions===
	'''30-meter geometry.''' The geometry of the instrument measurement, based on a viewing distance of 30 m from an arbitrary passenger vehicle with an eye height of 1.2 m and a single headlight mounting height of 0.65 m in the same vertical plane and a pavement stripe directly ahead of the headlight.		'''30-meter geometry.''' The geometry of the instrument measurement, based on a viewing distance of 30 m from an arbitrary passenger vehicle with an eye height of 1.2 m and a single headlight mounting height of 0.65 m in the same vertical plane and a pavement stripe directly ahead of the headlight.

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	'''Retroreflectivity.''' The measure of the retroreflective quality of the pavement markings. The unit of measure is expressed as millicandela per meter squared per lux or mcd/m<sup>2</sup>/lux.		'''Retroreflectivity.''' The measure of the retroreflective quality of the pavement markings. The unit of measure is expressed as millicandela per meter squared per lux or mcd/m<sup>2</sup>/lux.

	==620.13.2 Equipment==		==620.16.2 Equipment==
	The apparatus shall consist of a handheld 30-meter geometry retroreflectometer, such as the Mirolux 30 retroreflectometer or ART Stripemaster retroreflectometer.		The apparatus shall consist of a handheld 30-meter geometry retroreflectometer, such as the Mirolux 30 retroreflectometer or ART Stripemaster retroreflectometer.

	==620.13.3 Procedure==		==620.16.3 Procedure==

	'''620.13.3.1''' For new pavement markings, measurement of retroreflectivity should be delayed in accordance with [https://epg.modot.org/index.php/620.~~12_Construction_Inspection_for_Sec_620~~#620.12.2.3_Inspection_.28Sec_620.2.3.29 EPG 620.12.2.3].		'''620.16.3.1''' For new pavement markings, measurement of retroreflectivity should be delayed in accordance with [https://epg.modot.org/index.php/620.15_Construction_Inspection_for_Sec_620#620.15.2.3_Inspection_.28Sec_620.2.3.29 EPG 620.15.2.3].

	'''620.13.3.2''' For existing pavement markings, measurements may be taken any time the pavement markings are clean and dry. After snow events, measurements shall not be taken until there has been a rain event that washes away all salt residue.		'''620.16.3.2''' For existing pavement markings, measurements may be taken any time the pavement markings are clean and dry. After snow events, measurements shall not be taken until there has been a rain event that washes away all salt residue.

	'''620.13.3.3''' Take all measurements in the sampling areas in the direction of traffic flow, except on the centerline of two-lane roads, then take the required number of measurements in each direction. Measure both single and double lines, and apply the acceptance criteria for each line in both directions.		'''620.16.3.3''' Take all measurements in the sampling areas in the direction of traffic flow, except on the centerline of two-lane roads, then take the required number of measurements in each direction. Measure both single and double lines, and apply the acceptance criteria for each line in both directions.

	'''620.13.3.4''' Because handheld retroreflectometers normally shoot a beam of light approximately 6 in. to 12 in. in front of the machine’s lens, locate the unit approximately 6 in. to 12 in. from the pavement marking to be read.		'''620.16.3.4''' Because handheld retroreflectometers normally shoot a beam of light approximately 6 in. to 12 in. in front of the machine’s lens, locate the unit approximately 6 in. to 12 in. from the pavement marking to be read.

	'''620.13.3.5''' When selecting a checkpoint for existing markings, care should be taken to find a section of pavement marking that is typical for the section of road. Measurements should not be taken within close proximity of side roads, entrances or other areas where extreme wear of the pavement markings may occur.		'''620.16.3.5''' When selecting a checkpoint for existing markings, care should be taken to find a section of pavement marking that is typical for the section of road. Measurements should not be taken within close proximity of side roads, entrances or other areas where extreme wear of the pavement markings may occur.

	==620.13.4 Sampling==		==620.16.4 Sampling==
	===620.13.4.1 Solid Longitudinal Lines===		===620.16.4.1 Solid Longitudinal Lines===
	====620.13.4.1.1 Road Lengths < 1000 Ft.====		====620.16.4.1.1 Road Lengths < 1000 Ft.====
	Randomly select one 300 ft. section of pavement marking for testing. Take measurements approximately every 15 ft. along the pavement marking line. Take a total sample size of 20 measurements.		Randomly select one 300 ft. section of pavement marking for testing. Take measurements approximately every 15 ft. along the pavement marking line. Take a total sample size of 20 measurements.

	====620.13.4.1.2 1000 Ft. < Road Lengths < One Mile====		====620.16.4.1.2 1000 Ft. < Road Lengths < One Mile====
	Break the roadway to be tested down into segments of equivalent lengths. Keep the segment lengths as close as possible to 1000 ft., but the segments may be as small as 500 ft., as would be the case when the total roadway length to be tested is only 1001 ft. long. Within each segment, randomly select one 300 ft. section of pavement marking for testing. Take measurements within the 300 ft. sections of roadway approximately every 15 ft. along the pavement marking line. Take a total sample size of 20 measurements for each section.		Break the roadway to be tested down into segments of equivalent lengths. Keep the segment lengths as close as possible to 1000 ft., but the segments may be as small as 500 ft., as would be the case when the total roadway length to be tested is only 1001 ft. long. Within each segment, randomly select one 300 ft. section of pavement marking for testing. Take measurements within the 300 ft. sections of roadway approximately every 15 ft. along the pavement marking line. Take a total sample size of 20 measurements for each section.

	====620.13.4.1.3 One Mile < Road Length < Six Miles====		====620.16.4.1.3 One Mile < Road Length < Six Miles====
	Checkpoint areas shall be taken at the start, midpoint and end zones of roads greater than one mile long. Take measurements within each checkpoint with a sample size of 20 measurements taken every 15 ft. within the check point.		Checkpoint areas shall be taken at the start, midpoint and end zones of roads greater than one mile long. Take measurements within each checkpoint with a sample size of 20 measurements taken every 15 ft. within the check point.

	====620.13.4.1.4 Road Length > Six Miles====		====620.16.4.1.4 Road Length > Six Miles====
	Checkpoint areas shall be located at the start and end of the road and at intervals of every 3 mi. within the length of road. Take measurements within each checkpoint with a sample size of 20 measurements taken every 15 ft. within the check point.		Checkpoint areas shall be located at the start and end of the road and at intervals of every 3 mi. within the length of road. Take measurements within each checkpoint with a sample size of 20 measurements taken every 15 ft. within the check point.

	===620.13.4.2 Intermittent Longitudinal Lines===		===620.16.4.2 Intermittent Longitudinal Lines===
	====620.13.4.2.1 Road Lengths < 1000 Ft.====		====620.16.4.2.1 Road Lengths < 1000 Ft.====
	Take two measurements on 10 random intermittent pavement markings, giving a total sample size of 20 measurements. Take measurements on each intermittent pavement marking at minimum 3 ft. apart.		Take two measurements on 10 random intermittent pavement markings, giving a total sample size of 20 measurements. Take measurements on each intermittent pavement marking at minimum 3 ft. apart.

	====620.13.4.2.2 1000 Ft. < Road Lengths < One Mile====		====620.16.4.2.2 1000 Ft. < Road Lengths < One Mile====
	Break the roadway to be tested down into segments of equivalent lengths. Keep the segment lengths as close as possible to 1000 ft., but the segments may be as small as 500 ft., as would be the case when the total roadway length to be tested is only 1001 ft. long. Within each segment, randomly select one 300 ft. section of pavement marking for testing. Within each 300 ft. section, take two measurements on 10 random intermittent pavement markings, giving a total sample size of 20 measurements for each section. Take measurements on each intermittent pavement marking at minimum 3 ft. apart.		Break the roadway to be tested down into segments of equivalent lengths. Keep the segment lengths as close as possible to 1000 ft., but the segments may be as small as 500 ft., as would be the case when the total roadway length to be tested is only 1001 ft. long. Within each segment, randomly select one 300 ft. section of pavement marking for testing. Within each 300 ft. section, take two measurements on 10 random intermittent pavement markings, giving a total sample size of 20 measurements for each section. Take measurements on each intermittent pavement marking at minimum 3 ft. apart.

	====620.13.4.2.3 One Mile < Road Length < Six Miles====		====620.16.4.2.3 One Mile < Road Length < Six Miles====
	Checkpoint areas shall be taken at the start, midpoint and end zones of roads greater than one mile long. Two measurements shall be taken on each of 10 consecutive intermittent pavement markings for a total sample size of 20 measurements in each checkpoint. The random measurement on an intermittent marking shall be separated by at least 3 feet.		Checkpoint areas shall be taken at the start, midpoint and end zones of roads greater than one mile long. Two measurements shall be taken on each of 10 consecutive intermittent pavement markings for a total sample size of 20 measurements in each checkpoint. The random measurement on an intermittent marking shall be separated by at least 3 feet.

	====620.13.4.2.4 Road Length > Six Miles====		====620.16.4.2.4 Road Length > Six Miles====
	Checkpoint areas shall be located at the start and end of the road and at intervals of every 3 mi. within the length of road. Within each checkpoint two measurements shall be taken on each of 10 consecutive intermittent pavement markings for a total sample size of 20 measurements.		Checkpoint areas shall be located at the start and end of the road and at intervals of every 3 mi. within the length of road. Within each checkpoint two measurements shall be taken on each of 10 consecutive intermittent pavement markings for a total sample size of 20 measurements.

	==620.13.5 Acceptance==		==620.16.5 Acceptance==
	*At each checkpoint, the average of the 20 sample readings shall be calculated. This is the average sample reading.		*At each checkpoint, the average of the 20 sample readings shall be calculated. This is the average sample reading.

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	\|}		\|}

	[[~~Image~~:620.11 Hand Held Retroreflectometer Readings.gif\|center]]		[[File:Figure 620.11 Hand Held Retroreflectometer Readings.gif\|center]]

	~~[[Category:620 Pavement Marking~~]]

Hoskir: Hoskir moved page 620.13 Measurement of Retroreflectivity by Handheld Retroreflectometers to 620.16 Measurement of Retroreflectivity by Handheld Retroreflectometers: renumbered and renamed due to MUTCD Update (See Special Ballot)

2026-01-06T16:07:14Z

Hoskir moved page 620.13 Measurement of Retroreflectivity by Handheld Retroreflectometers to 620.16 Measurement of Retroreflectivity by Handheld Retroreflectometers: renumbered and renamed due to MUTCD Update (See Special Ballot)

← Older revision	Revision as of 11:07, 6 January 2026
(No difference)

Smithk: Updated website link (for increased security)

2021-10-22T17:44:50Z

Updated website link (for increased security)

← Older revision		Revision as of 12:44, 22 October 2021
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	==620.13.3 Procedure==		==620.13.3 Procedure==

	'''620.13.3.1''' For new pavement markings, measurement of retroreflectivity should be delayed in accordance with [~~http~~://epg.modot.org/index.php/620.12_Construction_Inspection_for_Sec_620#620.12.2.3_Inspection_.28Sec_620.2.3.29 EPG 620.12.2.3].		'''620.13.3.1''' For new pavement markings, measurement of retroreflectivity should be delayed in accordance with [https://epg.modot.org/index.php/620.12_Construction_Inspection_for_Sec_620#620.12.2.3_Inspection_.28Sec_620.2.3.29 EPG 620.12.2.3].

	'''620.13.3.2''' For existing pavement markings, measurements may be taken any time the pavement markings are clean and dry. After snow events, measurements shall not be taken until there has been a rain event that washes away all salt residue.		'''620.13.3.2''' For existing pavement markings, measurements may be taken any time the pavement markings are clean and dry. After snow events, measurements shall not be taken until there has been a rain event that washes away all salt residue.

Smithk: Per TS, minor revisions

2020-07-24T16:07:09Z

Per TS, minor revisions

← Older revision		Revision as of 11:07, 24 July 2020
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	[[image:620 Retroreflectivity reading.jpg\|right\|400 px]]		[[image:620 Retroreflectivity reading.jpg\|right\|400 px]]

	The following guidelines are based on MoDOT Test Method ~~T80~~ and ASTM D7585-10.		The following guidelines are based on MoDOT Test Method TM80 and ASTM D7585-10.

	These guidelines are to be used by MoDOT forces when determining the quality and remaining life of MoDOT pavement markings, both existing and newly applied.		These guidelines are to be used by MoDOT forces when determining the quality and remaining life of MoDOT pavement markings, both existing and newly applied.
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	====620.13.4.2.3 One Mile < Road Length < Six Miles====		====620.13.4.2.3 One Mile < Road Length < Six Miles====
	Checkpoint areas shall be taken at the start, midpoint and end zones of roads greater than one mile long. Two measurements shall be taken on each of 10 consecutive intermittent pavement markings for a total sample size of 20 measurements in each checkpoint. The random measurement on a intermittent marking shall be separated by at least 3 feet.		Checkpoint areas shall be taken at the start, midpoint and end zones of roads greater than one mile long. Two measurements shall be taken on each of 10 consecutive intermittent pavement markings for a total sample size of 20 measurements in each checkpoint. The random measurement on an intermittent marking shall be separated by at least 3 feet.

	====620.13.4.2.4 Road Length > Six Miles====		====620.13.4.2.4 Road Length > Six Miles====

Smithk: /* 620.13.3 Procedure */ Revised to accord with Sec 620.40

2018-09-26T14:57:04Z

620.13.3 Procedure: Revised to accord with Sec 620.40

← Older revision		Revision as of 09:57, 26 September 2018
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	==620.13.3 Procedure==		==620.13.3 Procedure==

	'''620.13.3.1''' For new pavement markings, ~~take the pavement marking measurements between seven and fourteen days after application~~. Waiting seven days ensures that all excess glass spheres have been removed, and completing the measurements by fourteen days allow retest of the pavement marking within 45 days if the handheld retroreflectometer measurements are questioned due to operator or retroreflectometer concerns.		'''620.13.3.1''' For new pavement markings, measurement of retroreflectivity should be delayed in accordance with [http://epg.modot.org/index.php/620.12_Construction_Inspection_for_Sec_620#620.12.2.3_Inspection_.28Sec_620.2.3.29 EPG 620.12.2.3].

	'''620.13.3.2''' For existing pavement markings, measurements may be taken any time the pavement markings are clean and dry. After snow events, measurements shall not be taken until there has been a rain event that washes away all salt residue.		'''620.13.3.2''' For existing pavement markings, measurements may be taken any time the pavement markings are clean and dry. After snow events, measurements shall not be taken until there has been a rain event that washes away all salt residue.

Smithk: Per TS, eliminated Mem’l Day striping goal, use of double dropped wet reflective elements, & grooving on constr’n project if a durable pavem’t marking product is not being used.

2015-02-25T18:40:13Z

Per TS, eliminated Mem’l Day striping goal, use of double dropped wet reflective elements, & grooving on constr’n project if a durable pavem’t marking product is not being used.

← Older revision		Revision as of 13:40, 25 February 2015
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	\|width="500"\| New Pavement Markings \|\| align="center"\| 300 \|\| align="center"\|225		\|width="500"\| New Pavement Markings \|\| align="center"\| 300 \|\| align="center"\|225
	\|-		\|-
	\| Existing Pavement Markings Expected to Last Through Winter \|\| align="center"\|200 \|\| align="center"\|175		\| Existing Pavement Markings Expected to Last Through Winter (measured in the fall)\|\| align="center"\|200 \|\| align="center"\|175
	\|-		\|-
	\| Pavement Marking Failure Point \|\| align="center"\|150 \|\| align="center"\|125		\| Pavement Marking Failure Point \|\| align="center"\|150 \|\| align="center"\|125

Smithk: /* 620.13.5 Acceptance */ Per Traffic, Pavement Marking Acceptance Table clarified

2014-10-22T12:25:43Z

620.13.5 Acceptance: Per Traffic, Pavement Marking Acceptance Table clarified

← Older revision		Revision as of 07:25, 22 October 2014
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	{\| border="1" class="wikitable" style="margin: 1em auto 1em auto"		{\| border="1" class="wikitable" style="margin: 1em auto 1em auto"
	\|-		\|-
	! Colspan="3" style="background:#BEBEBE"\|'''Pavement Marking Acceptance Table'''		! Colspan="3" style="background:#BEBEBE"\|'''Pavement Marking Acceptance Table, mcd/m<sup>2</sup>/lux'''
	\|-		\|-
	! !! style="background:#BEBEBE"\| ~~Yellow~~ !! style="background:#BEBEBE"\|~~White~~		! !! style="background:#BEBEBE" width="90"\| White !! style="background:#BEBEBE" width="90"\|Yellow
	\|-		\|-
	\| New Markings \|\| ~~225~~ \|\| ~~300~~		\|width="500"\| New Pavement Markings \|\| align="center"\| 300 \|\| align="center"\|225
	\|-		\|-
	\| Existing Markings \|\| ~~125~~ \|\| ~~150~~		\| Existing Pavement Markings Expected to Last Through Winter \|\| align="center"\|200 \|\| align="center"\|175
	\|-		\|-
	\| ~~Existing Markings Expected to Last Another Winter~~ \|\| ~~175~~ \|\| ~~200~~		\| Pavement Marking Failure Point \|\| align="center"\|150 \|\| align="center"\|125
	\|}		\|}

Smithk: Per CM, replaced the superseded ASTM reference with the current one

2013-10-21T15:22:17Z

Per CM, replaced the superseded ASTM reference with the current one

← Older revision		Revision as of 10:22, 21 October 2013
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	[[image:620 Retroreflectivity reading.jpg\|right\|400 px]]		[[image:620 Retroreflectivity reading.jpg\|right\|400 px]]

	The following guidelines are based on MoDOT Test Method T80 and ASTM ~~D 6359~~-99.		The following guidelines are based on MoDOT Test Method T80 and ASTM D7585-10.

	These guidelines are to be used by MoDOT forces when determining the quality and remaining life of MoDOT pavement markings, both existing and newly applied.		These guidelines are to be used by MoDOT forces when determining the quality and remaining life of MoDOT pavement markings, both existing and newly applied.

Smithk: Per Traffic and CM, revision to bring policy into substantial compliance with the 2009 MUTCD.

2012-01-18T19:57:56Z

Per Traffic and CM, revision to bring policy into substantial compliance with the 2009 MUTCD.

← Older revision		Revision as of 14:57, 18 January 2012
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	These guidelines are to be used by MoDOT forces when determining the quality and remaining life of MoDOT pavement markings, both existing and newly applied.		These guidelines are to be used by MoDOT forces when determining the quality and remaining life of MoDOT pavement markings, both existing and newly applied.

	==620.11.1 Scope==		==620.13.1 Scope==
	This method describes the procedure for retroreflectivity inspections of pavement markings using a handheld retroreflectometer.		This method describes the procedure for retroreflectivity inspections of pavement markings using a handheld retroreflectometer.

	===620.11.1.1 Definitions===		===620.13.1.1 Definitions===
	'''30-meter geometry.''' The geometry of the instrument measurement, based on a viewing distance of 30 m from an arbitrary passenger vehicle with an eye height of 1.2 m and a single headlight mounting height of 0.65 m in the same vertical plane and a pavement stripe directly ahead of the headlight.		'''30-meter geometry.''' The geometry of the instrument measurement, based on a viewing distance of 30 m from an arbitrary passenger vehicle with an eye height of 1.2 m and a single headlight mounting height of 0.65 m in the same vertical plane and a pavement stripe directly ahead of the headlight.

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	'''Retroreflectivity.''' The measure of the retroreflective quality of the pavement markings. The unit of measure is expressed as millicandela per meter squared per lux or mcd/m<sup>2</sup>/lux.		'''Retroreflectivity.''' The measure of the retroreflective quality of the pavement markings. The unit of measure is expressed as millicandela per meter squared per lux or mcd/m<sup>2</sup>/lux.

	==620.11.2 Equipment==		==620.13.2 Equipment==
	The apparatus shall consist of a handheld 30-meter geometry retroreflectometer, such as the Mirolux 30 retroreflectometer or ART Stripemaster retroreflectometer.		The apparatus shall consist of a handheld 30-meter geometry retroreflectometer, such as the Mirolux 30 retroreflectometer or ART Stripemaster retroreflectometer.

	==620.11.3 Procedure==		==620.13.3 Procedure==

	'''620.11.3.1''' For new pavement markings, take the pavement marking measurements between seven and fourteen days after application. Waiting seven days ensures that all excess glass spheres have been removed, and completing the measurements by fourteen days allow retest of the pavement marking within 45 days if the handheld retroreflectometer measurements are questioned due to operator or retroreflectometer concerns.		'''620.13.3.1''' For new pavement markings, take the pavement marking measurements between seven and fourteen days after application. Waiting seven days ensures that all excess glass spheres have been removed, and completing the measurements by fourteen days allow retest of the pavement marking within 45 days if the handheld retroreflectometer measurements are questioned due to operator or retroreflectometer concerns.

	'''620.11.3.2''' For existing pavement markings, measurements may be taken any time the pavement markings are clean and dry. After snow events, measurements shall not be taken until there has been a rain event that washes away all salt residue.		'''620.13.3.2''' For existing pavement markings, measurements may be taken any time the pavement markings are clean and dry. After snow events, measurements shall not be taken until there has been a rain event that washes away all salt residue.

	'''620.11.3.3''' Take all measurements in the sampling areas in the direction of traffic flow, except on the centerline of two-lane roads, then take the required number of measurements in each direction. Measure both single and double lines, and apply the acceptance criteria for each line in both directions.		'''620.13.3.3''' Take all measurements in the sampling areas in the direction of traffic flow, except on the centerline of two-lane roads, then take the required number of measurements in each direction. Measure both single and double lines, and apply the acceptance criteria for each line in both directions.

	'''620.11.3.4''' Because handheld retroreflectometers normally shoot a beam of light approximately 6 to 12 in. in front of the machine’s lens, locate the unit approximately 6 to 12 in. from the pavement marking to be read.		'''620.13.3.4''' Because handheld retroreflectometers normally shoot a beam of light approximately 6 in. to 12 in. in front of the machine’s lens, locate the unit approximately 6 in. to 12 in. from the pavement marking to be read.

	'''620.11.3.5''' When selecting a checkpoint for existing markings, care should be taken to find a section of pavement marking that is typical for the section of road. Measurements should not be taken within close proximity of side roads, entrances or other areas where extreme wear of the pavement markings may occur.		'''620.13.3.5''' When selecting a checkpoint for existing markings, care should be taken to find a section of pavement marking that is typical for the section of road. Measurements should not be taken within close proximity of side roads, entrances or other areas where extreme wear of the pavement markings may occur.

	==620.11.4 Sampling==		==620.13.4 Sampling==
	===620.11.4.1 Solid Longitudinal Lines===		===620.13.4.1 Solid Longitudinal Lines===
	====620.11.4.1.1 Road Lengths < 1000 ~~Feet~~====		====620.13.4.1.1 Road Lengths < 1000 Ft.====
	Randomly select one 300 ft. section of pavement marking for testing. Take measurements approximately every 15 ft. along the pavement marking line. Take a total sample size of 20 measurements.		Randomly select one 300 ft. section of pavement marking for testing. Take measurements approximately every 15 ft. along the pavement marking line. Take a total sample size of 20 measurements.

	====620.11.4.1.2 1000 ~~Feet~~ < Road Lengths < One Mile====		====620.13.4.1.2 1000 Ft. < Road Lengths < One Mile====
	Break the roadway to be tested down into segments of equivalent lengths. Keep the segment lengths as close as possible to 1000 ft., but the segments may be as small as 500 ft., as would be the case when the total roadway length to be tested is only 1001 ft. long. Within each segment, randomly select one 300 ft. section of pavement marking for testing. Take measurements within the 300 ft. sections of roadway approximately every 15 ft. along the pavement marking line. Take a total sample size of 20 measurements for each section.		Break the roadway to be tested down into segments of equivalent lengths. Keep the segment lengths as close as possible to 1000 ft., but the segments may be as small as 500 ft., as would be the case when the total roadway length to be tested is only 1001 ft. long. Within each segment, randomly select one 300 ft. section of pavement marking for testing. Take measurements within the 300 ft. sections of roadway approximately every 15 ft. along the pavement marking line. Take a total sample size of 20 measurements for each section.

	====620.11.4.1.3 One Mile < Road Length < Six Miles====		====620.13.4.1.3 One Mile < Road Length < Six Miles====
	Checkpoint areas shall be taken at the start, midpoint and end zones of roads greater than one mile long. Take measurements within each checkpoint with a sample size of 20 measurements taken every 15 ft. within the check point.		Checkpoint areas shall be taken at the start, midpoint and end zones of roads greater than one mile long. Take measurements within each checkpoint with a sample size of 20 measurements taken every 15 ft. within the check point.

	====620.11.4.1.4 Road Length > Six Miles====		====620.13.4.1.4 Road Length > Six Miles====
	Checkpoint areas shall be located at the start and end of the road and at intervals of every 3 mi. within the length of road. Take measurements within each checkpoint with a sample size of 20 measurements taken every 15 ft. within the check point.		Checkpoint areas shall be located at the start and end of the road and at intervals of every 3 mi. within the length of road. Take measurements within each checkpoint with a sample size of 20 measurements taken every 15 ft. within the check point.

	===620.11.4.2 Intermittent Longitudinal Lines===		===620.13.4.2 Intermittent Longitudinal Lines===
	====620.11.4.2.1 Road Lengths < 1000 ~~Feet~~====		====620.13.4.2.1 Road Lengths < 1000 Ft.====
	Take two measurements on 10 random intermittent pavement markings, giving a total sample size of 20 measurements. Take measurements on each intermittent pavement marking at minimum 3 ft. apart.		Take two measurements on 10 random intermittent pavement markings, giving a total sample size of 20 measurements. Take measurements on each intermittent pavement marking at minimum 3 ft. apart.

	====620.11.4.2.2 1000 ~~Feet~~ < Road Lengths < One Mile====		====620.13.4.2.2 1000 Ft. < Road Lengths < One Mile====
	Break the roadway to be tested down into segments of equivalent lengths. Keep the segment lengths as close as possible to 1000 ft., but the segments may be as small as 500 ft., as would be the case when the total roadway length to be tested is only 1001 ft. long. Within each segment, randomly select one 300 ft. section of pavement marking for testing. Within each 300 ft. section, take two measurements on 10 random intermittent pavement markings, giving a total sample size of 20 measurements for each section. Take measurements on each intermittent pavement marking at minimum 3 ft. apart.		Break the roadway to be tested down into segments of equivalent lengths. Keep the segment lengths as close as possible to 1000 ft., but the segments may be as small as 500 ft., as would be the case when the total roadway length to be tested is only 1001 ft. long. Within each segment, randomly select one 300 ft. section of pavement marking for testing. Within each 300 ft. section, take two measurements on 10 random intermittent pavement markings, giving a total sample size of 20 measurements for each section. Take measurements on each intermittent pavement marking at minimum 3 ft. apart.

	====620.11.4.2.3 One Mile < Road Length < Six Miles====		====620.13.4.2.3 One Mile < Road Length < Six Miles====
	Checkpoint areas shall be taken at the start, midpoint and end zones of roads greater than one mile long. Two measurements shall be taken on each of 10 consecutive intermittent pavement markings for a total sample size of 20 measurements in each checkpoint. The random measurement on a intermittent marking shall be separated by at least 3 ft.		Checkpoint areas shall be taken at the start, midpoint and end zones of roads greater than one mile long. Two measurements shall be taken on each of 10 consecutive intermittent pavement markings for a total sample size of 20 measurements in each checkpoint. The random measurement on a intermittent marking shall be separated by at least 3 feet.

	====620.11.4.2.4 Road Length > Six Miles====		====620.13.4.2.4 Road Length > Six Miles====
	Checkpoint areas shall be located at the start and end of the road and at intervals of every 3 mi. within the length of road. Within each checkpoint two measurements shall be taken on each of 10 consecutive intermittent pavement markings for a total sample size of 20 measurements.		Checkpoint areas shall be located at the start and end of the road and at intervals of every 3 mi. within the length of road. Within each checkpoint two measurements shall be taken on each of 10 consecutive intermittent pavement markings for a total sample size of 20 measurements.

	==620.11.5 Acceptance==		==620.13.5 Acceptance==
	*At each checkpoint, the average of the 20 sample readings shall be calculated. This is the average sample reading.		*At each checkpoint, the average of the 20 sample readings shall be calculated. This is the average sample reading.

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	[[Image:620.11 Hand Held Retroreflectometer Readings.gif]]		[[Image:620.11 Hand Held Retroreflectometer Readings.gif\|center]]

	[[Category:620 Pavement Marking]]		[[Category:620 Pavement Marking]]

Smithk: 620.11 Measurement of Retroreflectivity by Handheld Retroreflectometers moved to 620.13 Measurement of Retroreflectivity by Handheld Retroreflectometers: Per Traffic and CM, revision to bring policy into substantial compliance with the 2009 MUTCD.

2012-01-18T19:56:53Z

620.11 Measurement of Retroreflectivity by Handheld Retroreflectometers moved to 620.13 Measurement of Retroreflectivity by Handheld Retroreflectometers: Per Traffic and CM, revision to bring policy into substantial compliance with the 2009 MUTCD.

← Older revision	Revision as of 14:56, 18 January 2012
(No difference)