620.11 MoDOT Pavement Marking Materials

Pavement Marking Guidelines

		Divided Highways	Undivided Highways	Intersection Markings
Contractor Installations	Major Roads	Class 2 High Build Paint with Type L Beads	Class 2 High Build Paint with Type L Beads	Durable Intersection Marking Material
	Minor Roads	Not applicable	Class 1 High Build Paint with Type P Beads
MoDOT Installations	Major Roads – shall be striped annually unless retroreflectivity exceeds requirements for new pavement markings1	High Build Paint with Type L beads (60° and rising)	High Build Paint with Type P beads (60° and rising)	Durable Intersection Marking Material or High Build paint with Type P beads
	Regionally Significant Roads – shall be striped annually unless retroreflectivity exceeds requirements for new pavement markings1	Not applicable	High Build Paint with Type P beads (50° and rising) or Cold weather paint with Type PM beads (35° to 50°)
	Minor Roads≥400 AADT – maximum of 50% striped annually
	Minor Roads<400 AADT – maximum of 33.3% striped annually
	Surface Treatments
1 See Pavement Marking Acceptance Table

620.11.1 Permanent Pavement Markings

The selection of permanent pavement markings shall be based on the Pavement Marking Guidelines table.

Support. Contract work consists of furnishing and installing durable intersection markings, cold weather paint, high build waterborne paint, waterborne pavement marking, or epoxy.

Standard. On the final lift of resurfacing projects and on all new pavements, all pavement marking will be provided by contract. On surface treatment projects, all pavement marking will be provided by MoDOT.

All permanent marking materials shall be installed in accordance with the manufacturer's recommendations. Durable pavement markings, such as epoxy, used for lane lines shall be installed in a groove.

Guidance. For road segments with different pavement types less than 1,000 ft. long, such as a concrete bridge deck surrounded by asphalt, the pavement marking type for the surrounding pavement should be continued through the segment and contrast marking would not be required on the bridge deck.

Figure 620.11.1

Support. The materials that MoDOT uses for pavement marking are:

A. Waterborne Paint. This material is the standard paint used by contractors and MoDOT forces. MoDOT forces use waterborne for all long line applications, while contracts should specify it on minor routes. Waterborne paint may be applied at a wet thickness of 15 mils to 24 mils. It may also be used for intersection markings when the life of the pavement is not expected to outlast a more durable product (see Temporary Removable Pavement Marking Tape). See EPG 620.13.

B. High Build Waterborne Paint. High Build paint can be applied in a thicker layer than normal waterborne paint and it is used by contractors when specified. High build paint may be applied at a wet thickness of up to 35 mils. High Build is one of two options for material to be used in contractor installations on divided highways. See EPG 620.13.

C. Cold weather paint. This material is used in special situations when specified. Cold weather paint is a water-based material that can be used at lower temperatures. Cold weather paint is normally applied at a wet thickness of 15 mils. See EPG 620.13.

D. Durable Intersection Marking Materials. Due to the excessive wear experienced in and around intersections, durable marking materials (preformed thermoplastic, cold applied tapes, extruded / sprayed thermoplastic or plural component liquid) should be used to mark intersection markings (stop bars, yield bars, arrows, words, symbols, hash bars, shields, etc.). These materials will remain in place longer and reduce maintenance requirements.

E. Temporary Removable Pavement Marking Tape. Temporary removable tape is used to delineate traffic lanes during construction. Preformed removable tape does not require special equipment to install or remove, however material costs are high, so it may only be cost effective in small quantities. The primary advantage is that the removal of this tape is inexpensive and will not scar the pavement. The primary disadvantages of tape are the higher material cost and weather constraints for installation. When establishing contract times and milestones, the potential timing of paving activities and weather constraints should be considered when selecting temporary pavement marking. A pay item for removal of the marking tape will be included if removal is required. Marking tape shall be applied as per manufacturer’s recommendation.

F. Temporary Pavement Marking Tape. Temporary pavement marking tape is used in locations where the marking will be in place no more than two weeks. It is cost effective only in small quantities. Short-term pavement marking is not normally removed. If removal is required, removable tape is the preferred material. Short term marking should not be used for temporary lane transitions or bypasses. Marking tape shall be applied as per manufacturer’s recommendation.

G. Temporary Raised Pavement Markers. Temporary raised pavement markers are used on contract leveling course and resurfacing projects on two or three lane roadways with no passing zone center striping to provide a temporary centerline until permanent marking is replaced. Temporary raised pavement markers are used in combination with the NO CENTER LINE sign. Temporary markers should also be used to provide a temporary lane line on 2-lane roadways with climbing lanes. Temporary markers may also be used to supplement other pavement marking in areas where emphasis is needed, such as on bypasses and lane transitions.

Markers dividing two lanes of traffic in the same direction have one reflective face that is white in color. The edgeline markers with two lanes of traffic in the same direction are yellow for the left edgeline and white for the right edgeline. Markers dividing two lanes of traffic in opposite directions have two opposing reflective faces that are yellow in color. The edge line markers with two lanes in opposite directions are white.

See Standard Plan 620.10 for details on using temporary raised pavement markers.

Temporary raised pavement markers are used primarily on pavement surface treatment projects. Surface treatment is defined as any pavement surfacing as defined in Sec 413 of the Standard Specifications. Type 1 markers are used for temporary edgeline marking and as part of the "cluster" marking of temporary lane lines.

Temporary raised pavement markers do require removal after the permanent marking is in place. They do not require a pay item for removal.

Standard. Snow plowable raised pavement markers (SRPMs) are neither being installed new nor reinstalled on any more projects. If the district chooses to leave the SRPM’s in place, both the reflectors and the shoes shall be maintained. The districts must assure SRPMs that remain in the pavement are regularly inspected. Where cold milling is being done, the removal of the SRPMs is included in the cost of cold milling. On surface treatment and resurfacing projects SRPMs shall be removed before application of the surface treatment or resurfacing. SRPMs shall not be left in place and covered by surface treatment or resurfacing.

Support. The night visibility of pavement markings is a direct result of the presence and quantity of the spherical glass or ceramic "beads" that are embedded in the pavement marking material. There are several types of beads used by MoDOT.

A. Type P Beads. These are an intermediate blend of glass bead used by MoDOT forces and contractors when marking minor roadways. The "P" stands for performance.

B. Type L Beads. These are a “large” glass bead. These beads are used by MoDOT striping forces and contractors on major routes to provide a level of wet night time performance.

Support. See Standard Specifications for Highway Construction, Section 1048, for material specifications of pavement markings.

Guidance. MoDOT forces typically apply beads to the wet paint at the rate shown in EPG 620.11.2. On contractor applied pavement markings, the glass beads are applied at a rate determined by the contractor to meet the minimum retroreflectivity requirements of the contract.

The bead guns on the stripers should be calibrated frequently to assure the proper application rate of beads is being applied to the painted line. The frequency of these calibrations is dependent on the bead guns and their ability to maintain a constant flow of beads. The calibration should be accomplished using an appropriate bead calibration kit. These kits contain a table to calculate the appropriate flow of beads for a given speed of the striper. This calibration should be performed a minimum of once every week of operation.

Spot checks should be performed using two methods. The first method is accomplished with the aid of an aluminum sign panel placed ahead of the striper on which the paint, without beads, is to be applied and a mil thickness gauge used to read the wet paint mil thickness. The bead application rate should also be checked at this time by measuring the volume of beads being dispensed over a given time period. These methods should be used to calibrate the striper at the beginning of each day.

The second method involves checking the amount of material used, both paint and beads, versus the miles marked. This method should be used throughout the remainder of the day to verify the proper material application rates are being maintained.

620.11.1.1 Wet Reflective Marking

Wet reflective markings are no longer used by MoDOT.

620.11.1.2 Contrast Marking

Guidance. Contrast marking should be used to enhance the visibility of white markings on concrete pavements. On either new concrete surfaces or diamond grinding projects, lane lines should include contrast markings. Contrast markings consist of standard white markings with an additional width of black marking on each side. Contrast markings should be maintained until the pavement ages or greys so that normal markings are adequate.

620.11.2 Traffic Marking Paint Application Rates

Standard. Typical application rates are:

Table 620.11.2 Pavement Marking Materials

Typical Application Rates of Pavement Marking Materials
Material			Application Rate
Cold Weather Paint			15 mils min
Class 1 High Build Waterborne Paint			up to 18 mils (Minor Roads)
Class 2 High Build Waterborne Paint			22 mils min (Major Roads)
Epoxy			25 mils
Type PM Beads			10 lbs/100 sq. ft.
Type L Beads			15 lbs/100 sq. ft.
Yield Table for Liquid pavement Marking Materials
Applied wet mil thickness		Gallons used per mile of 4 in. line		Gallons used per mile of 6 in. line
15		16.5		24.8
18		19.7		29.6
20		21.9		32.9
22		24.2		36.3
25		27.4		41.1
30		32.9		49.4

Guidance. Water borne paint should not be heated above 100 degrees Fahrenheit (refer to EPG 620.13 for the application of water borne paint).

During marginal weather conditions at the end of the striping season, in November and December, cold weather paint should be used.

620.11.3 Temporary Pavement Markings

Support. Temporary pavement marking consists of furnishing, installing, and maintaining non-permanent pavement marking in work zones to provide guidance to drivers until the project is complete. Standard Plan 620.10 shows layouts for typical situations. There are several forms of temporary pavement markings which can be used, the selection of the type of marking is typically based on the type of work being performed and the duration of the project:

A. Temporary Pavement Marking Paint

1. Paint typically requires the use of large striping trucks to install resulting in a higher installation cost
2. Material costs are low making it cost effective to install in large quantities and over long stretches of roadway
3. It can be installed faster than other types of pavement marking material
4. placed under traffic
5. The primary disadvantage is that the removal of paint is expensive and will result in scarring of the pavement if applied to the final driving surface
6. A pay item for removal of paint will be included if removal is required

B. Temporary Removable Pavement Marking Tape

1. A preferred option over paint when a temporary marking must be applied to the final driving surface
2. The application of tape does not require the large striping trucks to install, only small hand operated carts so installation costs are lower compared to paint
3. The removal of this product does not require special equipment and does not scar the final driving surface resulting in a clean and low cost removal effort
4. The primary disadvantages are the material costs are high, the product will not work for temporary markings that must go through winter and the tape can peel up if traffic continually track over and/or turns on the tape possibly requiring additional maintenance and replacement over the duration of the installation, at no additional cost to MoDOT
5. A pay item for removal of the marking tape will be included if removal is required

C. Temporary Non-Removable Pavement Marking Tape

1. Non-Removable Tape has similar advantages and disadvantages as removable tape
2. This product is typically less expensive
3. This product is only used on pavements that are not the final driving surface, getting covered or removed as part of the resurfacing project
4. No pay item for removal will be included

D. Temporary Raised Pavement Markers

1. Temporary raised pavement markers are typically used on contract leveling course and resurfacing projects on two or three lane roadways to provide temporary markings until permanent marking is replaced
2. Temporary raised pavement markers are used in combination with the No Center Stripe sign described in EPG 616.10.3.
3. Temporary raised pavement markers are used to provide temporary guidance until the permanent pavement markings can be applied in 14 days or less. If temporary pavement marking must remain in place longer than 14 days, then a temporary paint should be used to supply guidance to motorists. If temporary paint is used, it shall be applied in the same location and patterns as the permanent pavement marking will be applied.
4. These markers are installed by hand requiring no special equipment or crews to install resulting is a lower cost installation.
5. The markers themselves are low cost for the length of roadway they address
6. Like tape, these markers can require maintenance and replacement over the duration of the installation, at no additional cost to MoDOT
7. Like tape, these markers are to be removed between intermediate lifts and after the permanent pavement marking is installed, with no pay item for removal being included
8. Temporary raised pavement markers may also be used to supplement other pavement marking in areas where emphasis is needed, such as on bypasses and lane transitions.
9. These markers should not be used for temporary lane transitions or bypasses.
10. Unlike paint or tape, temporary raised pavement markings do not mimic the permanent pavement marking patterns, but instead have unique installations based on the type of marking they are representing:

• Markers dividing two lanes of traffic in the same direction have one reflective face that is white in color.
• Markers dividing two lanes of traffic in opposite directions have two opposing reflective faces that are yellow in color.
• Edge line markers are yellow for the left edge line and white for the right edge line.
• Where markers are used to emphasize edge lines in sharp curves or tapers, recommended spacing is 15 feet.
• Where they are used to emphasize intermittent lines or solid lines in tangent sections, recommended spacing is 40 feet.
• Other spacing may be used according to conditions see EPG 620.2.11, Raised Pavement Markers.

Option. Temporary marking tape may be used to establish experimental lanes or intersection markings to determine the markings effectiveness prior to installing the permanent markings. It may also be used to mark temporary centerlines following spot sealing and patching operations.

Temporary pavement marking may be used as a short term replacement for existing marking for grinding, milling and resurfacing, but no direct payment is made to the contractor as described in Standard Specification Section 620.

Guidance. Temporary marking should be used with pay items where the traffic pattern has changed during construction due to bypasses, lane shifts, narrow lanes, etc.

When establishing contract times and milestones, the potential timing of paving activities and weather constraints should be considered when selecting temporary pavement marking.

Temporary pavement markings, other than temporary paint, should not be recommended for locations where it will be subject to heavy traffic for periods greater than 2 months, in areas of heavy turning movements or on short radius curves. In addition, it should not be used to provide pavement marking following completion of construction projects.

620.11.4 Obliteration of Pavement Markings

This work consists of removing all existing or temporary pavement marking which is conflicting or might mislead traffic. The exception is short term marking tape which should be in place two weeks or less.

During the process of detouring traffic around construction and maintenance areas and incorporating changes in traffic movements, it may be necessary to remove or obliterate inappropriate pavement markings on the roadway. If this is not done properly the original markings can misdirect traffic, resulting in possible conflicts for both motorists and workers.

Standard. The use of asphalt, black paint or other methods to cover conflicting markings shall not be allowed

All removal methods must comply with EPA and MDNR regulations concerning air quality and material disposal.

Guidance. Provisions should be made on the TCP for the removal of all conflicting or misleading markings. Pay items should be provided for removal of pavement marking when required.

Removal or obliteration of inappropriate pavement markings should be performed following the requirements outlined in the MoDOT Specifications for Highway Construction, Section 620.50.

Where pavement markings have been obliterated, nighttime inspections should be made to verify that the marking is no longer visible and does not interfere with the new pavement markings.