Section 3: Sign Inspection

General

All signs, including supports, should be inspected twice a year for:
  • position
  • damage
  • legibility
  • obvious indications of structural distress or failure
  • general condition.
One of the two annual inspections should be conducted at night to check legibility and retroreflectivity (see following subheading).
Inspections should be made by two persons, so one can take notes while the other drives.
All personnel who frequently travel the highways should be instructed to report any obscured or damaged signs. Maintenance personnel should be alert at all times, observing signs for legibility, position, and minor damage for which immediate remedial action can be taken.

Sign Retroreflectivity

Often, sign failure is simply due to loss of retroreflectivity after the background material begins to reach its life expectancy. This is the usual cause of failure of the large guide signs on expressways and freeways. Retroreflectivity failure usually occurs to a group of signs facing the same direction at about the same time, since they were usually installed at the same time.
If the signs are no longer reflective, they should be scheduled for immediate replacement. Overhead guide signs with non-reflective backgrounds should also be refurbished when legibility is impaired by fading or streaking of the background.
Reflective Sheeting Performance
Department Materials Specification
DMS-8300
, “Sign Face Materials,” defines
  • performance requirements
  • the manufacturer’s replacement obligation
  • the department’s obligation
  • many other pertinent items.
The performance requirements cover the following possible defects and their associated tolerances:
  • cracking
  • peeling
  • shrinkage
  • fading or loss of color
  • loss of reflectivity.
Sign inspectors should be aware of this specification and be familiar with the sheeting application requirements and warranties.
The retroreflective quality of the sheeting material deteriorates over time, eventually requiring replacement of the sign. Premature failures of the sheeting should be reported to the Traffic Materials Branch of the Construction Division.

Inspection Report

Documentation of sign inspections is important to a successful sign program. Sign inspectors should fill out an inspection report for each inspection run. The reports should be filed at the district office with a copy retained by the maintenance supervisor. Typically a sign inspection report should include:
  • the date
  • the maintenance section
  • the supervisor’s signature
  • the inspector’s signature
  • the roadways checked and findings
  • immediate action taken
  • future action needed
  • comments.