729Traffic Paint

TRAFFIC PAINT

SCOPE

729.01.01 Material Covered. These specifications cover ready mixed traffic marking paint to be applied to

either asphaltic or Portland cement concrete pavements.

REQUIREMENTS

729.02.01 General. Provide paint free from foreign materials, such as dirt, sand, fibers from bags, or other

material capable of clogging screens, valves, pumps, or other equipment used in a paint striping apparatus.

Grind the paint pigment and properly disperse in the vehicle. The dispersions sha ll be of such nature that the pigment does not cake or thicken in the container, and does not become granular or curdled. Any settlement of pigment in the paint shall be a thoroughly wetted, soft mass permitting the complete and easy vertical penetration of a paddle. Settled pigment shall be easily redispersed, with minimum resistance to the sideways manual motion of the paddle across the bottom of the container, to form a smooth uniform product of the proper consistency.

The specified amounts and materials used in each formula for achieving satisfactory pigment wetting and suspension, may be varied or changed to suit the vendor’s method of manufacture. Paint made with any deviations in antisettling, wetting agents, or stablizers shall still be required to conform to the characteristics of the finished paint and all other requirements of these specifications.

.02 Packaging. Prepare manufactured paint at the factory ready for application. Do not add thinner or

other material to the paint after the paint has been shipped.

All shipping containers must comply with Department of Transportation Code of Federal Regulations, Hazardous Materials Regulations Board, Reference 49 CFR.

Properly seal all containers with suitable gaskets and which show no evidence of leakage.

Label all containers of paint showing the exact title of the specification, manufacturer’s name, date of manufacture, and manufacturer’s batch number.

Show precautions concerning the handling and application of paint on the label of the paint container.

The lining of the containers shall be of such character as to resist the solvent of this paint and to prevent skins being loosened into the body of the paint.

.03 Certificates. Ship the material to the job site in containers that are substantial and plainly marked

with the manufacturer’s name and address, the color of the material, date of manufacture, and batch number.

The material manufacturer shall furnish a notarized certification that the material complies with the provisions of this specification. It shall not be inferred that the provisions of a certification of compliance waives Department inspection, sampling, or testing.

PHYSICAL PROPERTIES AND TESTS

729.03.01 Sampling and Testing. Samples will be taken after delivery

The Department reserves the right to have an inspector present to observe the manufacturing process. Furnish a complete formulation record of the manufacturing process to the Materials Division. Tests will be performed according to ASTM, Federal Test Method Standards No. 141 and methods designated by the Materials Division of the Department.

.02 Materials. The raw materials for use in the paint formula shall conform to the specifications

designated by Federal serial number or paint material code number hereinafter specified. Subsequent amendments to the specifications quoted shall apply to all raw materials and finished products.

Paint shall also comply with the paint formulation requirements of the appropriate Subsections below. 585

.03 Epoxy Paint Marking Material. Use epoxy paint formulations listed in the QPL

designed to provide a simple volumetric mixing ratio of two components (e.g. tw o volumes of Part A to one volume Part B).

White Yellow Organic Yellow Pigments Titanium Dioxide, ASTM D476 Type II or III .......................................................... 18-25% ................... — .................... 16-25% Chrome Yellow, ASTM D211 Type III ................................ ........................................ — .................... 23-30% .................. 5-9%

Binder Epoxy Resin ................................ ................................ ................................ ......... 75-82% ............... 70-77% ................ 70-75%

both white and yellow Component A on a pigment free basis.

per ASTM D2074.

injurious to persons or property.

coincide, within 10%, at a recommended spray temperature. Component B shall be formulated so as to have a steady and constant viscosity at temperatures recommended for spray application.

150 mm (3 x 6 in.) aluminum panels at 380 μm ± 25 μm (15 mils ± 1 mil) in thickness with no glass beads and exposed in a Q.U.V. Envi ronmental Testing Chamber as described in ASTM G154, shall conform to the following requirements. (The test shall be conducted for 75 hours at 50 °C (122 °F), 4 hours humidity and 4 hours U.V., in alternating cycles. The prepared panels shall be cured at 2 5 °C (77 °F) for 72 hours before exposure). The color of the white epoxy paint system shall not be darker than Federal Standard Color No. 17778 as shown in Table VIII of Federal Standard No. 595B. The color of the yellow epoxy system shall be reasonably cl ose to Federal Standard Color No. 13538 as shown in Table IV of Federal Standard No. 595B. The gloss values of both samples shall not be less than 70 (prism geometry of 60) after the test.

at 380 μm ± 13 μm (15 mils ± 0.5 mil) wet film thickness at 25 °C ± 1 ° C (77 ° F ± 2 °F) and with the proper saturation of glass spheres, shall exhibit no tracking time when tested according to ASTM D711 in less than 45 minutes.

of 4 °C (40 °F) or above.

ACI Method 503, shall have such adhesion to the concrete surface that there shall be a 100% concrete failure in the performance of this test. The concrete specimens for the test shall be equivalent to Portland Cement Concrete Pavement per Section 409 with a minimum Compressive strength of 28 MPa (4,000 psi). The prepared specimens shall be conditioned at 25 °C ± 1 ° C (77 ° F ± 2 ° F) for a minimum of 24 hours and a maximum of 72 hours before the performance of the t ests indicated.

have a Shore D Hardness greater than 75. Samples shall be allowed to cure at 25 °C ± 1 °C (77 °F ± 2 °F) for a minimum of 24 hours and a m aximum of 72 hours before performing the indicated test.

load and CS -17 wheels. The duration of test shall be 1,000 cycles. The wear index for the cat alyzed material shall not be more than 80 as calculated based on ASTM D4060. The tests shall be run on cured samples of material which have been applied at a film thickness of 380 μm ± 13 μm (15 mils ± 0.5 mil). The samples shall be allowed to cure at 25 °C ± 1 ° C (77 ° F ± 2 ° F) for a minimum of 24 hours and a maximum of 72 hours before performing the indicated tests. 586

have a tensile strength of not less than 41 MPa (6,000 psi). The Type IV Specimens shall be cast in a suitable mold and pulled at a rate of 6 mm (1/4 in.) per minute by a suitable dynamic testing machine. The samples shall be allowed to cure at 25 °C ± 1 °C (77 ° F ± 2 °F) for a minimum of 24 hours and a maximum of 72 hours before performing the indicated tests.

marking materials shall have a compressive strength of not less than 8 3 MPa (12,000 psi). The cast sample shall be conditioned at 25 °C ± 1 ° C (77 °F ± 2 ° F) for a minimum of 72 hours before performing the indicated tests. The rate of compression of these samples shall be no more than 6 mm (1/4 in.) per minute.

with the reference infrared spectrum on file with the Department’s Materials Division.

.04 Waterborne Paint Marking Material. Use waterborne paint formulations listed in the QPL

waterborne white and yellow traffic line marking paint for application on Portland cement concrete and bituminous pavements. It shall be easily and uniformly applicable with mechanical airless or air assisted spray marking equipment at paint temperatures up to 38 ° C (100 ° F). The paint shall serve as a binder for glass beads in such a manner as to produce maximum adhesion and reflection.

formulations listed in the QPL.

intended white and yellow formulations to the Engineer for approval at least 20 days before any paint is delivered to field locations. Furnish the batch formulation which will be used in manufacturing of the paint, a test report, Material Safety Data Sheet, and all product specification data along with the preliminary sample.

The Engineer will forward the preliminary sample and required documentation to the Headquarters Materials Division. The Materials Division will verify that the formulations meet the specifications and develop baseline requirements for subsequent paint shipment to field locations.

shall be considered part of the formulation and shall be mixed with the paint after delivery and before sampling.

The Department reserves the right to have an inspector present to observe the manufacturing process. Also, the Department reserves the right to require test reports of samples delivered to field locations from the manufacturer.

infrared spectral analysis.

Other acrylic emulsions may be submitted for approval if the following requirements are met:

formulated with the approved acrylic emulsions.

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tests between the paint formulated with the approved and proposed acrylic emulsions on both asphalt and concrete surfaces. The Contractor or a third party may conduct road tests. However, the submission of the required test data is the responsibility of the Contractor. Road test shall include:

all the specifications for waterborne traffic paint. Also, alternative paint formulations require appr oval by the Department prior to their use.

hexavalent chromium, toluene, chlorinated solvents, hydrolyzable chlorine derivatives, ethylene based glycol ethers and their acetates, nor any carcinogen, as defined in 29 CFR 1910.1200. When tested as specified in 7a, the lead content shall not exceed 0.06% by weight of the dry film and the test for chromium content shall be negative.

in Table I .

TABLE I —QUANTITATIVE REQUIREMENTS

Requirement Number Requirement White Yellow 1 Pigment: Percent by weight 62.0 ± 2 62.0 ± 2 2 Total Solids: Percent by weight, minimum 77.0 77.0 3 Nonvolatile Vehicle: Percent by weight vehicle, minimum 40.0 40.0 4 Consistency: Krebs -Stormer Shearing rate 200 rpm, Equivalent K.U. 80-95 80-95 5 Density: kilogram/Liter (lb/gal), minimum 1.65 (13.75) 1.60 (13.35) 6 Fineness of Grind: Hegman gauge, North Standard Scale, minimum 3 3 7 Drying Time, No -Pick-Up: Minutes, maximum 7 7 8 Directional Reflectance: minimum 89 58 9 Volatile Organic Content, VOC: g/L (lb/gal), maximum 150 (1.25) 150 (1.25) 10 Dry-Through, Early Washout: Minutes <125 <125 11 Dry Opacity, Type I: minimum Dry Opacity, Type II: minimum 0.92 0.95 0.92 0.95 12 Bleeding Ratio: minimum, 125 μm (5 mils) wet 0.97 0.97 13 Total Solids: Percent by volume, minimum 60 58 14 Wet Opacity: minimum, 125 μm (5 mils) wet 0.90 0.90 15 Mud Cracking at 1.52 mm (60 mils) wet, For Type II Paints Only PASS PASS

evidence of biological growth, corrosion of the container, livering or hard settling. The paint shall be dispersible by hand stirring for 5 minutes to a smooth and homogene ous consistency, exempt of gel structures, persistent foam or air bubbles.

uniform, free from grit, undispersed particles, craters and pinholes.

requirements of subparagraphs 6a and 6b. The sample shall show no change in consistency greater than 5 K.U. from the value in Table I.

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panel is bent 180 degrees over a 13 mm (1/2 in.) mandrel.

wrinkle, lose adhesion, change color , or show other evidence of deterioration.

flocculation, change in consistency greater than 10 K.U. from the value in Table I, nor a decrease in scrub resistance by more than 10% of the requirement in subparagraph 6m.

paint shall match the specified Federal Standard 595B color number within _ E of 6.0 CIELAB units.

the daylight directional reflectance specified in Table I.

color number 33538 when tested according to subparagraph 7i(4).

gelling or other instability. The consistency shall be in compliance with Table I.

dry-through time less than 125 minutes.

shall require not less than 150 liters (40 gal) of sand to abrade the paint film through to the substrate.

shall be in conformance with subparagraph 6g. The directional reflectance of white paint shall meet the requirement in Table I. After performing the scrub resistance test according to subparagraph 7l, the paint shall be in conformance with subparagraph 6m.

remove the paint film.

a maximum of 23.7 g/L (0.20 lb/gal) Rutile titanium dioxide. The white paint shall contain a minimum of 120 g/L (1.00 lb/gal) Rutile titanium dioxide.

a no pic k up condition under traffic when applied at 380 μm ± 25 μm (15 mils ± 1 mil) wet film thickness in 40 to 90 seconds.

otherwise specified.

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will be performed at standard conditions, which are 25 °C ± 1 ° C (77 ° F ± 2 ° F) and 50% ± 5% relative humidity. Test results will be evaluated for conformance to requirements. The sample shall be unacceptable if any test result is not in conformance with the corresponding requirements in subparagraph 6 and Table I.

TABLE II —TEST METHODS

Characteristic Requirement Subparagraph FED-STD 141 ASTM Method Test Subparagraph Lead Content 4e — D3335 7a(1) Chromium Content 4e — D3718 7a(2) Condition in Container 6a — — 7b Appearance 6b — — 7c Accelerated Package Stability 6c — D1849 7d Flexibility 6d — D522 7e Water Resistance 6e — — 7f Freeze -Thaw Stability 6f — D2243 7h Color 6g — D2244 7i Directional Reflectance 6g(2) — E1347 7i(2) Yellow Color Match 6g(3) — D1729 7i(4) Heat -Shear Stability 6h — — 7m Skinning 6i — — 7n Dry-Through, Early Washout 6j 3021 D1640 7o Abrasion Resistance 6k — D968 7g Accelerated Weathering 6l — G154 7j Scrub Resistance 6m 2013 D2486 7l Volatile Organic Content Table I — D3723 — Nonvolatile Vehicle Table I — D2369 — Consistency Table I — D562 — Total Solids by Weight Table I — D3723 — Dry Opacity Table I — — 7k Dry Time, No -Pick-Up Table I 4121 D711 — Fineness of Dispersion Table I — D1210 — Bleeding Ratio Table I — D969 — Pigment, % by Mass Table I — D3723 — Titanium Dioxide 6n — D1394 7p Density Table I — D1475 — Wet Opacity Table I — — 7q Mud Cracking, Type II Paint Only Table I — — 7r

spectrometer according to the manufacturer’s manual. The x -ray method shall be used in case of dispute. Evaluate for compliance with subparagraph 4e.

extracted pigment contained in a centrifuge tube. Agitate by shaking and centrifuge. A yellow color in the supematant liquid indicates the presence of hexavalent chromium. If the results of the above test are inconclusive, then use the procedure in ASTM D3718 to test for chromium content. Evaluate resu lts for compliance with subparagraph 4e.

packaged, check for evidence of biological growth and corrosion. Then lower a spatula into the container and determine whether the paint has livered or developed hard settling. Disperse the paint with the spatula for 5 minutes and examine for compliance with subparagraph 6a.

allow to dry for 24 hours at standard conditions. Evaluate for conformance with subparagraph 6b. 590

the bulk sample from which the cans are filled is well stirred and uniform, that the containers used are clean, and that the lids are applied promptly to the cans to prevent evaporation losses. Store at a temperature of 52 °C (126 ° F) for 2 weeks. Evaluate following the procedure in ASTM D1849, except allow hand stirring for 5 minutes to ensure uniform distribution. Evaluate the consistency for conformance with Table I. Draw down the paint as in subparagraph 7c. Evaluate for conformance with subparagraph 6c.

thickness of 0.13 mm (0.005 in.) on clean bare cold rolled steel panel. Air dry the panel for 24 hours at standard conditions, then bake for 5 hours at 105 °C ± 2 °C (221 ° F ± 4 ° F), and finally condition the panel for 30 minutes at standard conditions. Bend over a 13 mm (1/2 in.) diameter cylindrical mandrel and examine under a magnification of 7 diameters for compliance with subparagraph 6d.

of Fed. Test Method Standard No. 141. Draw down the paint to a wet film thickness of 0.33 mm (0.013 in.), and allow to dry in a horizontal position at standard conditions for 24 hours. Immerse one- half of the painted panel in distilled water at 25 °C ± 1 ° C (77 ° F ± 2 ° F). After 18 hours, remove the panel from the water and allow it to dry for two hours at standard conditions. Evaluate for conformance with subparagraph 6e.

(4 x 8 in.) to a dry film thickness of 0.102 to 0.107 mm (4 to 4.2 mils).

at 105 °C ± 2 ° C (221 ° F ± 4 ° F). After baking, condition the panels for 30 minutes at standard conditions and then run the abrasion test as specified in subparagraph 7g(4).

to accelerated weathering according to subparagraph 7j. Remove the panels and condition for 24 hours at standard conditions, and then run the abrasion test as specified in subparagraph 7g(4).

diameter of the metal guide tube shall be from 18.97 to 19.05 mm (0.74 to 0.75 in.). Five liters (1.3 gal) of unused sand shall be used for each test panel. The test shall be run on two test panels. Five liters (1.3 gal) of sand is approximately 7.94 kg (17.5 lb). Evaluate for compliance with subparagraph 6k.

according to ASTM D562 and the scrub resistance test as described in subparagraph 7l. Check for conformance with subparagraph 6f.

weathering according to ASTM E1347. Evaluate for conformance with T able I.

after weathering according to ASTM D2244 using CIE Illuminant D65 with the 10 degree standard observer. Evaluate for conformance withs ubparagraph 6g.

to ASTM D1729 with the daylight illumination represented by CIE Illuminant D75 or D65. Evaluate for conformance with subparagraph 6g(3).

aluminum panels prepared as described in Method 2013 of Fed. Test Method Standard No. 141. Air dry the sampl e 48 hours under standard conditions.

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exposure, 300 hours total, alternating 4 hour UV exposure at 60 ° C (140 °F), and 4 hours condensate exposure at 40 ° C (104 ° F).

directional reflectance and color match using the procedures in subparagraphs 7 i(2) and 7i(3). Evaluate for conformance with the color requirements in subparagraph 6g. Using the procedure described in subparagraph 7l, run the scrub resistance test. Evaluate for conformance with subparagraph 6m .

film thickness shall be 0.13 mm (0.005 in.). Evaluate for conformance with Table I.

from the accelerated weathering test, subparagraph 7j, evaluate for conformance with subparagraph 6m.

The blender should have tight fitting lid and be taped to minimize volatile loss. When the paint reaches 65 ° C (149 °F), stop the blender immediately and apply cover. Let cool a minimum of 12 hours and examine for gelling or other signs of instability. Evaluate for compliance with subparagraph 6h.

Method 3021 of Fed. Test Method Standard 141. After 48 hours, examine for compliance with subparagraph 6i.

(0.013 in.). Immediately place in a humidity chamber maintained at 23 °C ± 2 °C (73 °F ± 4 °F) and 90% ± 3% relative humidity. Test according to ASTM D1640 except that the pressure exerted shall be the minimum needed to maintain contact with the thumb and film. Check for compliance with subparagraph 6j.

ASTM D1394. Evaluate for conformance with subparagraph 6n.

of 0.037 mm (0.0015 in.) over each of the dried test panels prepared for determining dry opacity, Method 4121 of Fed. Test Method Std. No. 141, Procedure B. Allow the panels to stand horizontally in a dust free atmosphere for 10 minutes at standard conditions, blot the excess oil, and perform the test.

paint 75 mm (3 in.) wide and at least 150 mm (6 in.) long, and having a 1.52 mm (60 mil) wet film thickness. Allow the paint to dry for 48 hours at standard conditions on a horizontal surface. After 48 hours, the paint film shal l not contain any cracks.

otherwise specified.

“PROTECT FROM FREEZING —STORE ABOVE 2 °C (35 °F)”

“PROTECT FROM FREEZING —STORE ABOVE 2 °C (35 °F)”

“After opening, maintain a thin layer of water on surface of paint during storage to prevent skinning.”

“Use only in equipment designed for water based paints.”

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“This paint may be reflectorized by dropping glass beads conforming to Nevada Department of Transportation (NDOT) specifications onto the wet paint. The surface to be coated shall be free from dirt, oil, grease, other contaminants, and loose, peeling, or poorly bonded paint. The paint shall be applied to the surface at a wet film thickness of 0.41 mm (0.016 in.) minimum for Type I or 0.64 mm (0.025 in.) minimum for Type II, while air and surface temperatures are above 7 ° C (45 ° F) and rising.”

.0 5 Polyurea Paint Marking Material. Use polyurea paint formulations listed in the QPL

provide a simple volumetric mixing ratio of two components (e.g. two or three volumes of Part A to one volume Part B), that is free from heavy metals.

injurious to persons or property.

coincide, within 10%, at a recommended spray temperature. Component B shall be formulated so as to have a steady and constant viscosity at temperatures recommended for spray application.

(3 x 6 in.) aluminum panels at 380 μm ± 25 μm (15 mils ± 1 mil) in thickness with no glass beads and exposed in a Q.U.V. Environmental Testing Chamber as described in ASTM G154, shall conform to the following requirements. (The test shall be conducted for 75 hours at 50 ° C (122 ° F), 4 hours humidity and 4 hours U.V., in alternating cycles. The prepared panels shall be cured at 25 ° C (77 ° F) for 72 hours before exposure). The color of the white polyurea paint system shall not be darker than Federal Standard Color No. 17778 as shown in Table VIII of Federal Standard No. 595B. The color of the yellow polyurea system shall be reasonably close to Federal Standard Color No. 13538 as shown in Table IV of Federal Standard No. 595B. The color of the black polyurea paint marking material shall be reasonably close to Federal Standard Color No. 37038 as shown in Federal Standard No. 595B. The gloss values of both white and yellow samples shall not be less than 70 (prism geometry of 60) after the test.

thickness at 25 ° C ± 1 ° C (77 ° F ± 2 ° F) and with the proper saturation of glass spheres, the material shall exhibit no tracking time when tested according to ASTM D711 in less than 10 minutes.

or above.

the concrete surface that there shall be a 100% concrete failure in the performance of this test. The concrete specimens for the test shall be equivalent to Portland Cement Concrete Pavement per Section 409 with a minimum compressive strength of 28 MPa (4,000 psi). The prepared specimens shall be conditioned at 25 ° C ± 1 ° C (77 °F ± 2 °F) for a minimum of 24 hours and a maximum of 72 hours before the performance of the tests indicated.

than 70. Samples shall be allowed to cure at 25 °C ± 1 °C (77 ° F ± 2 °F) for a minimum of 24 hours and a maximum of 72 hours before performing the indicated test.

and CS -17 wheels. The duration of test shall be 1,000 cycles. The weight loss for the catalyzed material shall be not more than 120 mg as calculated based on ASTM D4060. The tests shall be run on cured samples of material, which have been applied at a film thickness of 380 μm ± 13 μm (15 mils ± 0.5 mil). The samples shall be allowed to cure at 25 °C ± 1 ° C (77 ° F ± 2 ° F) for a minimum of 24 hours and a maximum of 72 hours before performi ng the indicated tests.

less than 24 MPa (3,500 psi). The Type IV Specimens shall be cast in a suitable mold and pulled at a rate of 6 mm (1/4 in.) per minute by a suitable dynamic testing machine. The samples shall be allowed to cure at 25 ° C ± 1 °C (77 °F ± 2 °F) for a minimum of 24 hours and a maximum of 72 hours before performing the indicated tests.

the reference infrared spectrum on file with the Department’s Materials Division.

593

TRAFFIC BEADS

SCOPE

730.01.01 Materials Covered. This specification covers the quality requirements of traffic beads and reflective

elements for dropping or spraying on pavement markings.

PHYSICAL PROPERTIES AND TESTS

730.02.01 Requirements. Furnish certifications which shall include or have attached specific results of tests

performed for roundness, refractive index, flow characteristics, and gradation. The certifications shall show the quantity and lot number.

or excessive air bubbles, and essentially clean from surface scarring or scratching. They shall be spherical in shape and at least 70% shall be true spheres when tested according to ASTM D1155, Procedure A or Microfiche Reader method.

The moisture content of the beads shall not exceed 0.01% by mass when tested at 105 ° C (221 °F) for 3 hours.

The refractive index of the spheres shall be a minimum of 1.50 as deter mined by the liquid immersion method at 25 °C (77 ° F).

The silica content of the glass spheres shall not be less than 60%. The glass spheres shall have the following gradation when tested according to ASTM D1214:

Type I Type II Sieve Size % Retained by Mass Sieve Size % Retained by Mass 2.00 mm (No. 10) ............................. 0 850 μm (No. 20) ............................ 0-5 1.70 mm (No. 12) ............................ 0-5 600 μm (No. 30) ............................ 5-20 1.40 mm (No. 14) ........................... 5-20 300 μm (No. 50) ........................... 30-75 1.18 mm (No. 16) .......................... 40-80 180 μm (No. 80) ............................ 9-32 1.00 mm (No. 18) .......................... 10-40 Pan ................................ ...... 0-10 850 μm (No. 20) ............................. 0-5 Pan ................................ ....... 0-2

Glass spheres shall be coated with a silane- type adherence coating to enhance its embedment in, and adherence to, the applied binder film. The coated beads shall emit a yellow -green fluorescence w hen tested by the Dansyl Chloride test procedure.

Glass spheres shall be treated with a moisture- proof coating. Glass beads shall show no tendency to absorb moisture in storage and shall remain free of clusters and lumps. They shall flow freely from dispensing equipment at any time when surface and atmospheric conditions are satisfactory for marking operations. The moisture- resistance of the glass sphere shall be determined on the basis of the following test:

Place 900 g (2 lb) of spheres in a washed cotton bag, having a thread count of 80 per 1,000 mm2 (50 per in.2) (warp and woof) and immerse the bag in a container of water for 30 seconds. Remove the bag and force excess water from the sample by squeezing the bag. Suspend and allow to drain for two hours at 21 to 22 ° C (70 to 72 ° F). Then mix the sample in the bag shaking thoroughly. Transfer a sample slowly to clean, dry glass funnel having a stem 100 mm (4 in.) in length, with a 9.5 mm (3/8 in.) inside diameter stem entrance opening and a minimum exit opening of 6 mm (1/4 in.). The entire sample shall flow freely through the funnel without stoppage. When first introduced into the funnel, if the sphere clogs, it is permissible to lightly tap the funnel to initiate the flow.

spherically shaped, free of milkiness, pits , or excessive bubbles.

The glass beads shall have a minimum of 80% rounds per screen for the two highest sieve quantities. The remaining sieve fractions shall be no less than 75% rounds. Beads shall be tested for roundness using ASTM D1155 or the Microfiche Reader method. 595