U.S. Department of Transportation
Federal Highway Administration
1200 New Jersey Avenue, SE
Washington, DC 20590
202-366-4000
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The PMMS software is a Windows” based Paradox@ data base scripted program. The software is designed for Windows version 95/98 or NT version 4.0 or higher. The software is designed as a “run-time” application, and is therefore a royalty free program. In other words, installing Paradox is not required to install and add information to the program. However, in the scripted format the program will only allow user to input the information. To fully utilize the program users will need to have a full version of Paradox, or another comparable data base program. Paradox is a commercially available program, which can be run within any Windows environment. This program assumes nothing about an operator’s level of computer knowledge. We have strived to develop a program that can be used by even the most novice computer user.
Entering information into the program is accomplished by entering the data directly into a scripted form. This program has been designed so that all relevant data can be entered directly into one of two screens: the daily maintenance, or contracted screen.
This program takes advantages of many Windows programming options. Keep in mind that you can use the right mouse button on parts of data input screen. Although you can move through the menus to do most things in the PMMS program, using the right click on your mouse will reveal additional menus that can save time. Highlighting (i.e., left clicking in the appropriate box) the District, Job, or Empl. ID portions of the input screen, and then right clicking the mouse button will allow access their sub-menus. Each of these sub-menus can be chanaed to fit soecific needs.
| Component | Description/Comments |
|---|---|
| Microprocessor | 486 or higher |
| RAM | 6MB (8MB is recommended.) Performance will increase with more memory. |
| Hard disk | A hard disk is required. System files installed using this minimum Paradox installation requires approximately 8 MB. |
| Video monitor | EGA or higher |
| Microsoft Windows | Version 95, 98, or later NT 4.0 |
| Mouse | Although not required, a mouse is strongly recommended. Some design features can be accessed only with a mouse. |
Conducting field surveys of the condition of pavement marking is not easy. Many aspects need to be considered prior to conducting field surveys. For example, markings are considered new within 14 days of installation, with all excess glass beads removed. When or how long after installation should retroreflectivity tests be taken? The fact is that it depends on the type of marking. Some markings can be read immediately after installation, and some should be allowed to brighten before their retroreflectivity is determined. Performance contracts for pavement markings are showing up throughout the United States across the country. And many of these contracts specify when readings will be taken.
Other items that should be considered prior to field inspection:
There are many factors (e.g., road surface, safety needs, alignment, material type) to be considered before pavement markings are installed. There is no one part or link in a pavement marking value chain that is more important then any other. One of the underlying premises of PMMS is that field inspections, or more specifically, the retroreflectivity of pavement markings, must be collected.
The following is included for consideration purposes only, and is not intended to take the place of any specific agency or organization specifications. It is provided as information to those agencies that have not performed field inspections. Agencies may also want to consider the following standards
ASTM Standards
Other Standards
The following specifies a procedure that can be used to evaluate the retroreflective performance of horizontally applied (in-service) pavement markings. This test
procedure is only intended for field measurement. Because the entrance and
observation angles of the retroreflectometer affect the readings of pavement markings
the entrance and observation angles (geometry) shall be specified. Evaluation of
pavement markings shall be done within specified zones and time intervals. Criteria are
included for determining inspection zones that appear, by visual or mobile instrument
inspection, to fall below the specified minimum performance value.
Retroreflective field data can be collected with either portable (i.e., handheld) or mobile
reflectometers. The Engineer has the option of determining whether the readings shall
be done at night or during daylight, but in either case the readings will be done in dry
conditions. Data shall be collected in the direction of traffic, when ambient temperature
conditions are compatible with specifications for the instrument. When encountering
pavement markings that separate opposing traffic (i.e., centerline, lane line, skip lines,
etc.), the Engineer may request that pavement markings be evaluated in both
directions, and that the centerline be measured for each stripe.
This process is an improvement over visual inspections because it allows collection of
data that can be used to objectively determine the retroreflective qualities of the
installation. We do not intend to discourage visual inspections, especially visual
inspections done at night. Visual nighttime inspections are encouraged because they
may reveal deficient areas that should be inspected.
30-Meter Measurement Geometry
Instrument geometry is specified because it is a primary driver in determining
retroreflective values. Thirty meters has been selected because it most closely
correlates an average automobile drivers vision geometry. Instruments used to
measure the retroreflective properties of pavement markings shall conform to the
following measurement geometry(s):
. The entrance angle (the angle between the illumination axis and the retroreflector
axis) shall be ~88.50’ and <88.76’, and the observation angle (the angle between
the illumination axis and the observation axis) shall be 21 .O” and (I .05’. The coviewing
angle (the complement of the entrance angle) shall be 12.29’ and 52.50’ .
All readings taken, or the coefficient of retroreflected luminance, shall be expressed as
the metric equivalent (mcd/m’/lux).
Scheduling for Data Collection and Reporting
Field evaluations (data collection) should not be started until the markings have been inservice
for a minimum of 2 weeks. The 2-week minimum time frame is very dependent
on the type of material that is being installed. Data collection should be completed
within 6 weeks of installation (weather permitting). Waiting any longer could jeopardize
the ability of some marking material to meet minimum values. This is especially true for
areas with high volumes of traffic or areas where vehicles make numerous turning
movements.
After field evaluations are completed, a written report shall be submitted to the Engineer
Contained within the report shall be:
. State project number
l The test date
. Average of the readings at each test location
l Standard deviation (one deviation)
. Geographical location of the test site(s), including distance from the nearest
permanent site identification (such as a reference point/mile marker)
l Identification of the pavement marking material tested: type, color, age, and
transverse location on the road
l Identification of the retroreflectometer
. Remarks concerning the overall condition of the line, such as carryover of asphalt,
snowplow damage, uneven distribution of beads, etc.
Method for Determining Portable Reflectometers Measurement Zones, and
Minimum Sampling Rates
The evaluation of longitudinal pavement markings shall be made after identifying the
zone(s) to be measured. Any installation less than 300 meters (1000 feet) shall be
considered a zone. One zone of measurement should be identified for installations that
fall between 300 meters and 1.5 kilometers. Any installation greater than 1.5 kilometer
shall have a minimum of one zone selected for each kilometer of striping. The 300
meters shall be continuous in length. The random segment(s) may be selected after a
visual inspection. A minimum of 26 readings on each line will be taken within each test
zone. When reading broken lines (skip stripes), every other skip shall be read, with no
more then three readings taken on any one skip stripe. A minimum of two readings
should be taken on individual skip lines, and they should be taken approximately 500
millimeters (20 inches) from each end of the skip. On continuous lines, break the
measurement zone into a minimum of ten 30-meter (IOO-foot) areas, and space the 25
readings a minimum of 33 feet apart but no more than 100 feet apart. The Engineer
may determine that more samples shall be taken.
Note: After the initial evaluation, regardless of the results, the-Engineer can define new
checkpoint areas if they are considered critical for road safety.
Method for Determining Dynamic (Mobile) Measurement Zones, and Minimum
Sampling Rates
Mobile instruments shall conform to specified geometry and shall be capable of
reporting both mcd/m*/lux average and standard deviation for each line and each
segment. When reading longitudinal lines, the minimum interval for averaging both, a
segment’s individual mcd/m*/lux readings and the segment’s standard deviation will be
no less than 100 feet; however, all of the individual readings shall be used when
determining a zone’s overall average. Inspectors shall not group together, in any one
report, two lines or two color lines in the same data file. When collecting data on
longitudinal continuous lines, readings shall be collected at a minimum rate of not more
than 8 feet apart. When collecting data on longitudinal broken lines, readings shall be
collected at a minimum rate of not more than 5 feet apart.
Repeatability of the mobile instrument shall be considered acceptable if the instruments
deviation within the same inspection zone is +I 0%. The maximum acceptable deviation
for measurements made by two different instruments manufactured by the same
manufacturer, within the same zone of measurement, shall not be greater than’+15%.
The calibration of the instrument shall conform to the manufacturers instructions.
Mobile instruments shall measure a minimum of 20% of each installed line. And,
reading entire segments of installed lines should be considered.
Note: Upon evaluation, despite the results of the inspection, the Engineer can define
additional inspection areas if they are considered, critical for road safety.
Symbols and Legends
For each contract, the zone of measurement can be considered as the contract length.
Inspectors shall take and report a representative sample of each type of symbol.
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