Use of high intensity reflective sheeting in lieu of external lighting of overhead roadway signs.
Advanced Search
Select up to three search categories and corresponding keywords using the fields to the right. Refer to the Help section for more detailed instructions.

Search our Collections & Repository

All these words:

For very narrow results

This exact word or phrase:

When looking for a specific result

Any of these words:

Best used for discovery & interchangable words

None of these words:

Recommended to be used in conjunction with other fields



Publication Date Range:


Document Data


Document Type:






Clear All

Query Builder

Query box

Clear All

For additional assistance using the Custom Query please check out our Help Page


Use of high intensity reflective sheeting in lieu of external lighting of overhead roadway signs.

Filetype[PDF-1.37 MB]

  • English

  • Details:

    • Corporate Creators:
    • Publication/ Report Number:
    • Resource Type:
    • Geographical Coverage:
    • NTL Classification:
    • Abstract:
      Effective highway signing is an important component of driver decision making, comfort, and

      safety. Like many agencies across the country, overhead sign lighting has been used by the Florida

      Department of Transportation (FDOT) to improve visibility. However, the availability of newer and more

      efficient retroreflective materials has created a new challenge for state transportation agencies going

      through sign upgrade programs and considering the need for sign lighting. FDOT initiated this study to

      investigate whether high intensity reflective sheeting can be used to replace overhead sign lighting.

      Field data was collected to assess the conditions of Florida signs in terms of the MUTCD

      minimum maintained retroreflectivity levels. In addition, a luminance computation model was developed

      to calculate sign legend luminance under various situations, including different sign lighting technologies,

      different geometrics and sign locations, and different amounts of sign dirt and sign aging. By comparing

      the calculated luminance of a specific sign at a specific situation with the legibility luminance levels

      required by older drivers, sign lighting needs were assessed.

      A life-cycle cost spreadsheet was developed and used to calculate the cost of replacing the current

      sign sheeting in Florida with high reflective sheeting and the cost of installing/upgrading sign lighting.

      Based on this analysis, we found that under the conditions considered (either on straight and flat

      roadways or horizontal curves, in rural areas or urban areas), the most cost effective approach to maintain

      overhead guide luminance is to use (installing or replacing with) induction or LED luminaires. The results

      also indicate that a viable alternative (in terms of maintaining luminance and being cost effective) would

      be to use either Type VIII or Type XI legend sheeting materials and forgo sign lighting. For Type XI

      sheeting materials, sign lighting would be needed along horizontal curves in rural areas with radii of 880

      ft and horizontal curves in urban areas with radii of 2500 ft or less.

    • Format:
    • Main Document Checksum:
    • File Type:

    Supporting Files

    • No Additional Files

    More +

    You May Also Like

    Checkout today's featured content at

    Version 3.26