AASHTO M 247-09
Standard Specification for Glass Beads Used in Pavement Markings
American Association of State and Highway Transportation Officials / 2009 / 5 pages
1.1. This specification covers glass beads to be dropped or sprayed upon pavement markings so as to produce a reflectorized pavement marking.
1.2.1. Type 0—shall be known as a uniform gradation.
1.2.2. Type 1—shall be known as a standard gradation.
1.2.3. Types 2, 3, 4, and 5—shall be known as modified gradations.
1.3.1. Flotation—Any of the above gradation types may be obtained with oleophobic properties at the request of the purchaser (Note 1).
1.3.2. Moisture Resistance—Any of the above types may be obtained with hydrophobic properties if so specified by the purchaser.
1.3.3. Adherence—Any of the above types may be obtained with an adhesion coating is so specified by the purchaser.
Note 1—Any of the above types of beads may be specified with a combination of two of the above coatings. Dual coated beads must test positive for the presence of both specified properties.
1.4. The values stated in SI units are to be regarded as the standard.
1.5. This standard may involve hazardous materials, operations, and equipment. This standard does not purport to address all of the safety concerns associated with its use. It is the responsibility of the user of this standard to consult and establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use