Knowing what signs are on your roads allows the agency to develop a systematic sign maintenance program as well as to determine the amount of resources that will be needed to provide the desired level of traffic sign maintenance activities contained within the agency’s sign maintenance policies. An inventory can serve many purposes:
- Sign Life — when signs are installed, the installation date is labeled or recorded so that the age of a sign is known. Signs degrade over time and when combined with periodic night time inspections, an agency could determine when a sign has reached the end of its useful life.
- Manage and prioritize — an inventory that records the location of signs and recent maintenance activities can help establish the following:
- Where a single sign needs to be replaced.
- If a corridor needs sign improvements.
- When to clear back brush away from signs.
- Minimizing tort liability — an inventory can document the inspection and maintenance activities.
- Budgeting — an inventory can help manage resources for sign replacements on an annual or as-needed basis.
- Efficiency — combining work orders with the inventory allows the monitoring of signing activities and scheduling of maintenance activities.
Inventory systems can be simple manual card systems, but with the availability of several inexpensive and even free computer software packages, computer-based inventories are much more effective and are easy to use. Also by using global positioning systems (GPS) technology, signs can be easily and accurately located and mapped on geographic information systems (GIS). Computerized sign inventories are available through sign vendors or your Local Technical Assistance Program. An example of sign inventory can be found at the Utah LTAP website: http://www.utahltap.org/.
With a computerized sign inventory, the sign technician can easily record data while in the field.
The key to a successful inventory program is collecting the appropriate data elements and keeping it up to date. Table 3 shows the data elements that should be considered when developing an inventory.
Table 3. Data Elements for Sign Inventory.
| Data Element |
Description |
|
Sign Identification Number |
Unique number identifying sign |
|
Location |
Route name, distance, etc. depending on location reference system; could also be GPS latitude/longitude |
|
Sign Code |
Usually MUTCD designation |
|
Sign Position |
Location of sign relative to road (left, right, overhead) |
|
Offset |
Distance from edge of pavement |
|
Height |
Height of sign above road level |
|
Sign Size |
Width and height of sign |
|
Sheeting Type |
Grade of retroreflective material |
|
Installation Date |
Date when sign installed |
|
Post/Support Type |
Type of sign support (e.g. wood, tube) |
| Inspection Items |
Description |
|
Sign Condition |
Quality of sign based on visual inspection |
|
Retroreflectivity |
Measured value or visual assessment condition |
|
Maintenance Activity |
Type of maintenance last performed |
|
Inspection/Maintenance Date |
Date when sign was last inspected or maintained |
|
Inspector |
Name or initials of person who inspected or maintained sign |
|
Comments |
Supplementary notes about the sign |
Sign dating labels with anti-vandalism warnings can be applied to the back of the sign.