ASTM D4956

 

It is hoped that this information will assist the proper officials in making informed decisions regarding the materials they select for the traffic control devices on their roadways.This information was obtained from the Standard Specification for Retroreflective Sheeting for Traffic Control, ASTM Designation: D 4956-01, dated January 10, 2001. It has been summarized to provide the basic information regarding retroreflective sheeting types and adhesive backing classes. Technical information regarding the testing procedures that shall be followed to ensure conformance with ASTM specifications are available in the full version of the afore mentioned specification.

 

reboundable sheeting, n--retroreflective material intended to be attached to flexible impact resistant plastic devices, such as traffic drumlike channelizing devices

 

Retroreflective sheeting shall consist of a white or colored sheeting having a smooth outer surface and that essentially has the property of a retroreflector over its entire surface. There are nine types and five classes of retroreflective sheeting. Types are determined by conformance to the retrore- flectance, color, and durability requirements listed in section 6.1 of ASTM 4956-01 and may be of any construction providing that those requirements are met. Type designation is provided as a means for differentiating functional performance. Typical examples of applications are provided for descriptive information only and are not intended to be limitations or recommendations.

 

The typical applications for the retroreflective sheeting addressed in this specification are: Type Typical Application I Highway Signing, construction-zone devices, and delineators II Highway Signing, construction-zone devices, and delineators III Highway Signing, construction-zone devices, and delineators IV Highway Signing, construction-zone devices, and delineators V Delineators VI Temporary roll-up signs, warning signs, traffic cone collars, and post bands VII Highway Signing, construction-zone devices, and delineators VIII Highway Signing, construction-zone devices, and delineators IX Highway Signing, construction-zone devices, and delineators

Retroreflective sheeting shall he classified as follows: Type 1--A medium-intensity retroreflective sheeting referred to as 'engineering grade" and typically enclosed lens glass-bead sheeting. Typical applications for this material are permanent highway signing, construction zone devices, and delineators. Type II-- A medium-high-intensity retroreflective sheeting sometimes referred to as "super engineer grade" and typically enclosed lens glass-bead sheeting. Typical applications for this material are permanent highway signing, construction zone devices, and delineators. Type III-- A high-intensity retroreflective sheeting, that is typically encapsulated glass-bead retroreflective material. Typical applications for this material are permanent highway signing, construction zone devices, and delineators, Type IV-- A high-intensity retroreflective sheeting. This sheeting is typically an unmetallized microprismatic retroreflective element material. Typical applications for this material are permanent highway signing, construction zone devices, and delineators. Type V-- A super-high-intensity retroreflective sheeting. This sheeting is typically a metallized microprismatic retroreflective element material. This sheeting is typically used for delineators. Type VI-- An elastomerie high-intensity retroreflective sheeting without adhesive. This sheeting is typically a vinyl microprismatic retroreflective material. This sheeting is typically used for orange temporary roll-up warning signs, traffic cone collars, and post bands. Type VII-- A super-high-intensity retroreflective sheeting having highest retroreflectivity charac- teristics at long and medium road distances. This sheeting is typically an unmetallized microprismatic retroreflective element material. Typical applications for this material are permanent highway signing, construction zone devices, and delineators. Type VIII-- A super-high-intensity retroreflective sheeting having highest retroreflectivity charac- teristics at long and medium road distances. This sheeting is typically an unmetallized microprismatic retroreflective element material. Typical applications for this material are permanent highway signing, construction zone devices. and delineators. Type IX-- A very-high-intensity retroreflective sheeting having highest retroreflectivity charac- teristics at short road distances. This sheeting is typically an unmetallized microprismatic retroreflective element material. Typical applications for this material are permanent highway signing, construction zone devices, and delineators. Note 1 -- All retroreflective sheetings. but especially microprismatic sheetings, may have unique performance characteristics outside of the range of the standard geometries presented in the tables that define the types. Certain applications may require the use of a particular product within a particular type in order to achieve a desired level of retroreflectivity in a given situation. In these cases, information concerning additional performance characteristics must be obtained.