ASTM D4956-19 PDF Download

The ASTM D4956-19 standard is a specification that outlines the requirements for retroreflective sheeting used in traffic control devices. This includes flexible, non-exposed glass-bead lens and microprismatic sheeting that is used on signs, delineators, barricades, and other similar equipment. It should be noted that this standard does not cover the inks, overlays, or other imaging methods that may be applied to the retroreflective sheeting material.

The specification focuses on the photometric requirements of the retroreflective sheeting during evaluation, but it does not establish the minimum performance requirements for in-service signs or devices. These minimum performance requirements are addressed in separate documents and fall outside the scope of this particular standard.