By: Ernest Huckaby, Linda L. Brown, Charles Sears, Cherie Kittle, Scott Wainwright, Debra Chapell
For workers in the transportation construction industry,
going to work every day invites the potential for harm to themselves and
others. In the year 2000, over 1,000 people lost their lives to traffic
accidents in work zones. In a typical year, about 80% of those killed are
motorists, but the list also includes work-zone crew members, pedestrians, law
enforcement professionals, firefighters, emergency medical technicians and
others who put their lives on the line daily to meet America’s demands
for roadway infrastructure.
This danger is inherent in the effort to make our roads
safer and more efficient and to keep people and goods moving in America.
However, the risk of harm can be minimized with careful
applications of traffic control devices within the work zone. This article will
discuss the most recent version of the Manual on Uniform Traffic Control
Devices (MUTCD), focusing on traffic control in work zones and the differences
between this version and the previous one, published in 1988.
Orderly fashion
The U.S. Department of Transportation publishes the MUTCD. A
new Millennium Edition (also known as the 2000 MUTCD) became effective in early
2001. It is the eighth edition since the first publication in 1935, and it is
completely rewritten compared to the previous version published in 1988.
The purpose of the MUTCD is to promote highway safety and
efficiency by providing for the orderly movement of all road users on streets
and highways throughout the nation. The manual is the national standard and
federal law for the design and application of all traffic control devices.
The Federal Highway Administration (FHWA) has published the
official version of the manual on its web-site (http://mutcd.fhwa.dot.gov). Use
of web technology allows the FHWA to make information about manual changes
available to transportation professionals immediately after they are accepted
and approved. A glance at the MUTCD website shows that updates and
clarifications have already been incorporated into the Millennium Edition. The
site also provides an up-to-date reference source for other persons interested
in information on proper traffic control and operations.
Printed copies of the Millennium Edition can be purchased
through the national transportation associations—the American Association
of State Highway & Transportation Officials (www.aashto.org); the American
Traffic Safety Services Association (ATSSA, www.atssa.org); and the Institute
of Transportation Engineers (www.ite.org). At about 2,200 pages, some may find
the written version of the entire document inconvenient. To help navigate
through the manual, the American Public Works Association has a searchable
electronic version available for purchase on its website
(www.apwa.net/shop/asp/home. asp).
Also, ATSSA has printed a separate bound document containing only Parts
1, 5 and 6 of the manual—the parts that address work-zone traffic
control. Note, however, that these written copies will not contain the frequent
updates that can be found on the FHWA’s MUTCD website.
Traffic control devices—signs, signals, pavement
markings and others used to regulate, warn or guide road users—are
crucial to the safe and efficient operation of America’s roadways. They
become particularly important in work zones, where changing and unexpected
roadway conditions make it crucial that road users are properly guided through
the construction zone. The 2000 MUTCD contains important information on:
• Design
of safer work zones;
• Appropriate
signs to use under different work conditions; and
• Proper
placement of signs and workers to best inform motorists of construction
ahead.
The most important part
There are 10 separate parts to the MUTCD. Part 6 of the
manual is of particular interest to professionals involved in construction of
transportation facilities.
This section, titled “Temporary Traffic
Control,” contains important information, typical applications and
graphics to help construction workers understand the applications of the
various traffic control devices. It also serves to inform them of the proper
placement and maintenance of these devices within work zones.
Part 5 of the manual, “Low-Volume Rural Roads,”
addresses traffic control for roads with an average annual daily traffic flow
of less than 400 vehicles. It contains work-zone information that applies
specifically to less-used roads.
Temporarily unique
The title of Part 6 has changed from “Standards and
Guides for Traffic Control for Street and Highway Construction, Maintenance,
Utility, and Incident Management Operations” to the more succinct title
“Temporary Traffic Control” to reflect the fact that temporary work
zones involve unique traffic control conditions. Workers need to ensure their
own safety and that of the road users, while getting the necessary work done
and minimizing frustrating traffic delays.
The Millennium Edition offers important new signs and
markings for work zones. It also presents valuable information on devices used
to protect workers and roadway users. Described below are some of the more
significant changes in Part 6 that apply to construction zones:
• New
information on the use of shadow vehicles, truck-mounted attenuators and other
devices to improve worker safety;
• Guidance
on flagging procedures and specifications for retroreflective clothing
acceptable for flaggers and other road crew workers;
• A
new channelizing device called a “direction indicator barricade.”
This is a combination of typical barricade rails and a black-on-orange arrow
sign. It provides clearer warnings and directions for lane closures;
• New
sign mounting regulations requiring that, if a work-zone sign is to be in place
for more than three days, it must be mounted on a crashworthy device;
• New
regulatory and warning signs.
Several of these signs appeared in the 1993 Typical Application
diagrams, but there was no discussion of their proper use. These new signs are
described and illustrated in the manual;
• Increased
emphasis on pedestrians and bicyclists. The inclusion of pedestrians and
bicyclists is one of the most important revisions to the MUTCD. Important
information on the management of bicyclists through work zones has been added
to Part 6. New safety standards and guidance that further enhance the
protection afforded to pedestrians also have been added; and
• Enhanced
discussion of utilization of portable changeable message signs. These devices
are particularly effective in work zones where the messages communicated to
motorists may vary throughout the work zone. The 2000 MUTCD provides detailed
guidance on message flash rates, message content, acceptable abbreviations and
placement of the devices.
These are just a few of the changes in Part 6 of the 2000
MUTCD. Employees working in transportation construction will find it useful to
refer to the manual when planning and designing work zones. This will ensure
they are aware of changes from previous editions and they know about new
devices that are available and/or required to make the job safer.
Still experimenting
Finally, new research and experimentation continue to push
traffic control devices in new directions that increase safety and mobility.
Planned developments related to the MUTCD include: additional information on
minimum levels of retroreflectivity for signs and markings; weather research on
traffic control devices; and a new experimentation database that will be posted
on the MUTCD website.
Of specific interest to employees in the construction
industry is FHWA research that examines ways of increasing work-zone safety by
improving the visual transmission of information from the work zone to the
motorist. For example, a new color for signs used in incident management is
being considered. This would allow motorists to differentiate between planned
construction or maintenance work zones (identified by traditional
orange-and-black signs) and temporary incident management work zones associated
with major traffic incidents and other emergency situations, which would have
signs with a different color scheme.
Next steps
Now that the Millennium Edition of the MUTCD is in effect,
what impact does it have on jobs in the transportation construction industry?
First, it provides a common language for work crews to
communicate with road users because of the uniformity of traffic control
devices. This helps to ensure the safety and efficiency of the roadway system.
It also minimizes driver confusion.
Second, because of the numerous changes to the manual with
this edition, it will be essential that employees working in transportation
construction refer to it regularly, especially Part 6 which deals with traffic
control devices for use in work zones.
Hopefully, employees will find that the changes in this
edition make it easier for them to do their job, and will better help manage
traffic through work zones.
The manual officially became effective Jan. 17, 2001,
replacing the 1988 edition. By January 2003, the Millennium Edition’s new
provisions will become mandatory for all streets, highways and bicycle trails
in the U.S. Individual states may adopt their own regulations for traffic
control devices, provided they meet the minimum standards set by the
FHWA’s document. Workers in the transportation construction industry
should be aware that regulations may vary by state.
