- MUTCD
- The Manual on Uniform Traffic Control Devices, the federal standard for the signs, markings, signals, and temporary traffic control used on US roads.
- TTC (Temporary Traffic Control)
- The signs, devices, and layouts used to move traffic safely through or around a work area. MUTCD Part 6 sets the requirements.
- Work zone
- An area of a roadway where construction, maintenance, or utility work affects the normal movement of traffic, from the first warning sign through the end of the work.
- Taper
- A series of channelizing devices set at an angle to move traffic out of, or back into, its normal path, such as when a lane is closed. Its length depends on speed and lane width.
- Buffer space
- A protective, empty space in a work zone, either along the roadway or between traffic and the work area, that gives an errant vehicle room to stop.
- Channelizing device
- A device such as a cone, drum, tubular marker, or barricade used to guide traffic and mark the edges of a work area or a shifted path.
- Cone (traffic cone)
- A predominantly orange channelizing device, typically 18 or 28 inches or taller, used to mark work areas and guide traffic. Taller cones and retroreflective collars are used at higher speeds and at night.
- Delineator
- A retroreflective device mounted at the roadside or on a channelizing marker to show the alignment of the road, especially at night or in poor visibility.
- MASH
- The Manual for Assessing Safety Hardware, the current crash-test criteria that roadside and work-zone hardware must meet to be considered crashworthy.
- NCHRP-350
- The predecessor crash-test criteria to MASH. Older devices may still carry an NCHRP-350 rating, which has been superseded by MASH for new hardware.
- Crashworthy
- Describes hardware that has passed the applicable crash-test criteria (MASH or NCHRP-350) so it performs predictably when struck by a vehicle.
- ADA
- The Americans with Disabilities Act. Its 2010 Standards for Accessible Design set requirements for accessible parking, access aisles, and signage.
- Access aisle
- The marked, level space beside an accessible parking stall that lets a person transfer to and from a vehicle, including with a wheelchair or lift.
- Van-accessible space
- An accessible parking space with a wider access aisle and added clearance to accommodate a lift-equipped van, marked with an additional "van accessible" sign.
- International Symbol of Accessibility (ISA)
- The standard symbol, a stylized figure using a wheelchair, that marks accessible parking spaces, routes, and facilities.
- R7-8 sign
- The MUTCD sign that designates a reserved accessible parking space, showing the International Symbol of Accessibility. A "van accessible" plaque is added at van spaces.
- High-visibility safety apparel (Class 2 / Class 3)
- Garments made of fluorescent background and retroreflective material to make workers visible. Class 3 provides more coverage than Class 2 and is used at higher speeds and in lower visibility.
- ANSI/ISEA 107
- The consensus standard that defines the performance classes and material requirements for high-visibility safety apparel.
- Retroreflectivity
- The property that sends light back toward its source, such as a vehicle's headlights, making signs, apparel, and devices readable at night.
- Advance warning area
- The section of a work zone before the work itself where signs warn drivers of what is ahead and how to respond.
- Flagger
- A trained worker who controls traffic through a work zone using a stop/slow paddle or, in limited cases, a flag, following MUTCD procedures.
- Right-of-way
- The land dedicated to a road or highway, and separately, the legal right of one road user to proceed ahead of another.
- Passenger loading zone
- A designated curb or off-street area for picking up and dropping off passengers, which may carry accessibility requirements of its own.
- Tow-away zone
- An area, marked by signage, where parked or standing vehicles may be towed. Requirements for the signs and notice are often set by state or local law.
Informational only, not legal advice. Always confirm against the current edition of each standard and your state manual.