Content area
Full Text
HILLSBOROUGH COUNTY, FL, USA, CONDUCTED A STUDY TO ASSESS THE POTENTIAL IMPACT ON ITS LOCAL TRAFFIC PROGRAM OF PROPOSED FEDERAL GUIDELINES ON SIGN RETROREFLECTIVITY. A STATISTICAL SAMPLE OF RETROREFLECTIVITY DATA WAS COLLECTED, WHICH REPRESENTED A RANGE OF PHYSICAL CONDITIONS AND CLASSES OF COUNTY ROADWAY SIGNS.
INTRODUCTION
A major goal of the Federal Highway Administration (FHWA) is to provide a safe roadway system throughout the United States. In light of this goal, the development of minimum retroreflectivity levels for traffic signs and pavement markings has been one of the agency's key work programs for the last two decades.
These efforts have resulted in a revision of the Manual on Uniform Traffic Control Devices (MUTCD), pursuant to a Congressional mandate to "...include a standard for a minimum level of retroreflectivity that must be maintained for pavement markings and signs, which apply to all roads open to public travel."
In essence, roadway traffic signs and pavement markings must be readable and detectable by drivers, bicyclists and pedestrians at a sufficient distance during both daytime and nighttime conditions. Conferences, workshops and an active research program have been underway since 1984 to develop minimum retro reflectivity standards for traffic signs.
It has long been known that sign materials can degrade over time, making them undetectable to the public. This could result in an inconvenience to the public or could create potential safety concerns. Currently, FHWA suggests that no real objective measures are available for traffic engineers to determine when a roadway sign has reached the end of its useful life for nighttime visibility and should be replaced.1
During the course of the study described in this feature, a field research program was implemented to gather information on sign retroreflectivity with the objective of quantifying the potential impact to Hillsborough County, FL, USA's meeting these new recommended guidelines.
Previous studies completed by FHWA have suggested that signs within counties and cities would require increased compliance costs because these signs often are older and typically are composed of less expensive sheeting signs. The objective of this study was to specifically quantify the costs of compliance for Hillsborough County.
FIELD RESEARCH
Hillsborough County utilized the TransMap Corporation's mobile tracking and data collection system to inventory the county's traffic signs. Data were collected...