By: Christopher Bauer, P.E.
The clock is ticking.
By Jan. 1, 2012, all municipalities must have inspected all of the roadway signs in their jurisdiction for retroreflectivity and entered the data in a sign-management database in order to comply with a final rule published by the Federal Highway Administration (FHWA) in the Federal Register. Will your municipality be ready?
Retroreflectivity in sign sheeting bounces light from the vehicle headlights back toward the driver, which increases the legibility of signs at night and makes it easier for drivers to see and read the signs. Due to decreased visibility in the dark, nighttime driving is more dangerous than daytime driving. Even though nighttime traffic volumes are significantly lower in comparison to daytime traffic volumes, a disproportionate percentage of all traffic fatalities occur after dark. Proper retroreflectivity of signs can greatly increase visibility in the dark and therefore make the roads safer at night.
With this goal in mind, the FHWA published its final rule in the January 2008 Federal Register mandating new responsibilities and requirements for local government agencies to maintain minimum levels of sign retroreflectivity.
A must-do
The final rule has set forth several steps for compliance and their associated deadlines.
By January 2012, all local governments must:
- Select methods to assess the retroreflectivity of their roadway signage and to manage the signage maintenance and replacement process;
- Inventory all of their signs;
- Create a sign database to manage the data;
- Begin performing regular inspections of their signs; and
- Establish a procurement process that satisfies the material requirements set forth by the federal Manual on Uniform Traffic Control Devices (as well as any more stringent requirements of their state department of transportation).
By January 2015, all local governments must ensure that all regulatory, warning and ground-mounted guide signs (except street-name signs) comply with the minimum retroreflectivity requirements. By January 2018, all local governments must ensure all street-name signs and overhead guide signs comply with minimum retroreflectivity standards. But 2018 is not the end of the process. Because the retroreflective materials in sign sheeting degrade over time, local governments will need to continue updating their sign-management database indefinitely and replace the signs, as needed, to maintain the minimum levels of retroreflectivity required by law.
When to watch out
The FHWA has identified two primary techniques of determining when a sign complies with the federal rule: the assessment method and the management method. The assessment method evaluates each sign individually and notes whether or not it meets current standards. The management method forgoes individual evaluations and makes a determination of compliance for multiple signs based on certain factors such as age, location or the condition of control signs. Both techniques require the prerequisite sign inventory.
Sign assessment
Using the sign-assessment method, each sign is evaluated individually through visual inspection or measurement with a retroreflectometer.
Visual nighttime inspection
The retroreflectivity of an existing sign is assessed by a trained sign inspector conducting a visual inspection from a vehicle traveling at the posted speed limit during nighttime conditions. The retroreflectivity of existing signs is compared against a control panel of known, acceptable retroreflectivity.
Measurement with a retroreflectometer
An inspector uses a retroreflectometer to compare the retroreflective performance of signs against the minimum requirements of the federal rule.
While the measurement method requires the use of a retroreflectometer (which can be rented for several thousand dollars a month or purchased for approximately $15,000), this method provides a definitive retroreflective value that is highly tort defensible. In addition, it can be performed during the daytime, thereby eliminating the overtime or nighttime pay adjustment for staff required to perform the visual inspection.
Though the assessment method can be labor intensive, it ensures that no signs are replaced unnecessarily.
Sign management
Using the sign-management method, individual assessments of each sign are not necessary. Instead, signs are grouped according to a common characteristic, and multiple signs are replaced at the same time based on the compliance of that group. The FHWA has identified three methods of grouping the signs that are acceptable:
Expected sign life
Signs are replaced based on their age and the life span recommended by the manufacturer, which varies by the type of sheeting used. The average life span is approximately 10 years.
If the expected sign-life method is used, it requires the collection of sign installation dates as part of the sign inventory; these dates would then be used as a baseline for decisions regarding the need for replacement.
Blanket replacement All signs within a specified area or corridor are replaced based on the assumption that all the signs will require replacement in a given area. Following the first replacement of the signs, a baseline is then established that requires the signs to be replaced again within 10 years.
Control signs
The local government monitors and inspects a small sample of control signs and replaces signs in their jurisdiction based on when the control signs have reached the end of their useful life.
The advantage of the management method is that it doesn’t require the labor-intensive evaluation of each individual sign that the assessment method does. Unfortunately, this means sign-replacement decisions are not made based on the actual condition of the sign but on an assumption about its condition due to its age, its location or the condition of other signs. Thus, some signs will possibly be replaced unnecessarily.
Retroreflective materials in sign sheeting degrade over time, so regardless of the method a municipality chooses, it will need to be performed on a regular basis indefinitely in order to maintain the minimum retroreflectivity requirements mandated by the FHWA.
Combo deal
Typically, some combination of the assessment method and management method provides a best fit for municipalities. For example, one municipality in Pennsylvania with approximately 10,000 signs in its inventory is using the following methods to determine compliance:
- Blanket Replacement—The municipality will replace the signs at all signalized intersections during the scheduled yearly signal maintenance;
- xpected Life—When the installation date of signs is known (based on the year a subdivision within the community was constructed), the municipality will prioritize sign replacements based on the age of those installations; and
- Assessment Method Using a Reflectometer—The municipality will measure the retroreflectivity of signs on travel corridors, within high accident areas and other areas not covered by the two previous methods.
A complete inventory
Regardless of which method a municipality chooses to determine whether signs are in compliance, it must complete an inventory of all its signs. This requires gathering certain data for every sign such as its type, location, current condition and install date, if possible. Once the data has been obtained, it must be recorded and continually updated in some form of sign database. This database can be as simple as a spreadsheet, or it can be a more robust infrastructure inventory management system using GIS tools. The federal rule makes no requirement regarding the format or functionality of the database; therefore, each municipality can decide on a case-by-case basis which type of system is most appropriate based on the municipal need, available resources and the infrastructure the municipality has in place or is willing to institute. If a municipality already has a GIS database for other aspects of infrastructure inventory management, it may be advantageous to include the sign database as an additional data set.
The need to replace
Using condition ratings from the sign-inventory database, the municipality will be able to prioritize the replacement of noncompliant signs based on the needs of the community and budget for this expense. The federal rule allows several years to implement a replacement plan to achieve full compliance. This is time that can be used to spread the costs of sign replacements over several years. Regulatory, warning and ground-mounted guide signs must be compliant by January 2015. Other signs such as street-name signs and overhead guide signs must be compliant by January 2018.
Municipalities should begin planning for these deadlines now by choosing methods of assessing their signs and creating a sign inventory. Using the inventory and condition data, municipalities can then develop a plan of action for replacing those signs that do not comply with the federal rule.
About The Author: Bauer is the manager of transportation services for all offices of Herbert, Rowland & Grubic Inc.
