Are work zone signs required to be retroreflective?
All signs have to be retroreflective. For more information see section 2A.08 of the MUTCD. The standards for minimum levels are listed in section 2A.09. A link to section 2A of the National MUTCD is provided below.
While these regulations do not take effect until next year, it is wise to go ahead and start putting together a plan for meeting these standards. Please note that engineering grade sheeting will NOT meet the new standards for black on orange signs (work zones). Hi-intensity grade sheeting is preferred for most low-volume applications.