Knowledge Is Power

Chrisolas Management Services

Health & Safety Consultants

Knowledge Is Power

     
Training Courses
TCP - Flagger
TCT - Book 7
TCS - Supervisor
Traffic Plan Design
Services
Traffic Control Plans
Safety Consulting
Resources
Industry Links
Traffic Terminology
FAQ's
Software
Contact Us

Memorial

Paul Evans
 
Traffic Control Terminology

A » C   |  D » L  M » P   | Q » S |  T » Y

Maintenance
The upkeep of highways, traffic control devices, other transportation facilities, property and/or equipment.

Major Road
The principal route of two roads at an intersection. Also called Main Road.

Manoeuvre Time
The time to complete any required manoeuvre before reaching a sign, other traffic control device, or decision point.

Marker
See Construction Marker, Detour Marker, Object Marker.

Marking Symbol
A Pavement Marking graphical depiction used in a specific location to complement standard pavement markings, to guide, warn, regulate, or inform drivers where standard pavement markings alone would be less clear.

Master Controller (Traffic Signal)
An automatic device for supervising a system of controllers, maintaining definite time interrelationships, selecting among alternate available modes of operation or accomplishing other supervisory functions. A Master Controller which controls one or more Slave Controllers.

Matrix
A variable message sign display, made up of a series of dots (pixels) in a matrix format. Parameters or symbols are formed by illuminating different patterns of pixels.

Maximum Green (Traffic Signal)
The maximum time the right-of-way can be extended by actuations on a phase provided an actuation has been registered on a conflicting phase.

Maximum Speed
The maximum speed drivers are permitted to travel. The maximum speed is imposed by the Highway Traffic Act, or municipal by-laws. See also Normal Posted Regulatory Speed.

May
Indicates a permissive condition. No requirement for design or application is intended. However, mandatory requirements apply to some specific options if and when they are selected.

Measure
A physical device, traffic control device, regulation or other action which affects the movement of motor vehicles, bicycles, and/or pedestrians.

Measure of Effectiveness (MOE)
Parameters describing the quality of service provided by a traffic facility to drivers, passengers or pedestrians. Examples include speed, density, delay, and similar measures.

Median
That portion of a Divided Highway separating the travelled ways for traffic in opposite directions.

Median Barrier
A raised island, wall or structure located on the Centreline of a roadway through an intersection or along a road that prevents left turns or straight through movements from being made to and from a side street or private/commercial driveway.

Median Bikeway
A bikeway within the median of a highway.

Median Island
A zone or physical island constructed in the centre of the roadway to separate opposing directions of traffic

Median Strip
An expanse of hard surface material separating opposing lanes on a highway. The hard surface is flush or nearly flush with the adjacent lanes.

Merging
The convergence of separate streams of traffic into a single stream.

Microwave Radar Detection
A means of vehicle detection using microwave radar beams. Traffic parameters are calculated by measuring the return signal frequency from vehicles.

Midday Period
The period of time between the morning peak period (A.M. Peak Period) and the afternoon peak period (P.M. Peak Period).

Milling
The grinding off and removal of old asphalt for purposes of recycling and resurfacing. Milling may produce undesirable longitudinal grooves which affect behaviour of some vehicles.

Minimum Green (Traffic Signal)
The shortest time for which the right-of-way is given to a non-actuated phase" or to an actuated phase provided that an actuation has been registered for that phase.

Minimum Typical Guideline
Where so described, the guideline depicted in the typical layouts for Temporary Conditions represents the minimum requirements that must be achieved.

Minor Road
The lesser of two roads at an intersection.

MIST
Management Information System for Traffic.

Mobile Operations
Work that is done while moving continuously, usually at low speeds, or intermittently, with periodic, brief stops related to the mobile operation, which do not exceed a few minutes in duration (e.g., centreline or edgeline zone painting operations). The advance warning area (where required) moves with the activity area.

Modal Share
The percentage of people who use one particular mode of transportation.

Modal Split
(1) The proportion of person trips that uses each of the various specified modes of transportation-,

(2) The analytical process of separating total person trips into the modes of travel used-,

(3) A term that describes how many people use alternate forms of transportation.

It is frequently used to describe the percentage of people who use private automobiles, as opposed to the percentage who use public transportation.

Mode
Any of the following transportation methods: rail (intercity rail, commuter and urban transit)-, highway (automobiles, carpools, vanpools, bus transit, bicycles, pedestrians, and trucks): air,- water.

Module (Dynamic Message Sign)
A unit in a character matrix sign, which is comprised of several pixels and can display an individual character.

Module (Traffic Signal)
A removable assembly with a fixed pattern of pixels and identical to all other modules.

MONY-ITBCS
Michigan-Ontario-New York Intelligent Transportation Border Crossing System.

Motor Vehicle
Includes an automobile, motorcycle, motor-assisted bicycle (moped), and any other vehicle propelled or driven other than with muscular power, but does not include a streetcar, or other vehicles designed to operate on rails, or a motorized snow vehicle, traction engine, farm tractor and implements of husbandry or road-building machine.

Motor Vehicle Collision
A collision involving one or more motor vehicles.

Movement (Traffic Signal)
A movement is the direction of traffic flow and may be straight ahead (a "through movement"), a green left arrow (a "left-turn movement"), etc. Several movements may be allowed within a phase (such as with an advanced green arrow and a circular green display). In some cases, a movement is called a Faze since it is normally part of a Phase.

Moving Operation
See Mobile Operations.

Multi-lane Highway
A roadway with two or more travelled lanes carrying traffic in each direction.

Multi-modal
Refers to the availability of multiple transportation options, especially within a system or corridor. A multi-modal approach to transportation planning focuses on the most efficient way of getting people or goods from place to place, be it by truck, train, bicycle, automobile, airplane, bus, boat, foot or even a computer modem.

Multi-use Path
Any off-road dedicated facility for non-motorized traffic such as bicycles, pedestrians and in-line skaters.

Must
Indicates a mandatory condition. Where certain requirements in the design or application of the device are described with the "must" stipulation, it is mandatory that these requirements be met when an installation is made.

MUTCD
The Manual of Uniform Traffic Control Devices for Ontario, 1995.

MUTCDC
The Manual of Uniform Traffic Control Devices for Canada,1997.

MUTCD-US
The U.S. Manual of Uniform Traffic Control Devices, 1988 and (Part VI) 1993, and its subsequent revisions.

Narrow Lanes
Lanes in a work zone which are narrower than usual, as required by construction, maintenance, or utility operations. This may be done through partial lane -shifting (See Partial Lane Shift) in Short Duration operations, or through barrels and/or temporary concrete barriers (or equivalent) in Long Duration operations, in which case existing pavement markings should be removed and replaced by temporary pavement markings.

National Transportation Communications for ITS Protocols (NTCIP)
A family of communication protocols developed, or being developed, for the transportation community.

NCHRP
National Cooperative Highway Research Program (U.S.).

Neighbourhood
A cohesive urban area defined by geographic features, the road network or socioeconomic characteristics. With respect to traffic calming, neighbourhood boundaries are often defined by the arterial roadway network, which typically presents a significant barrier to travel and interaction.

Neighbourhood Transportation Management
A phrase often used to describe an approach which encompasses Traffic Calming Measures as well as design, operations, legal and other techniques to address transportation issues within a
Neighbourhood, such as speeding and excessive volumes or conflicts.

Neural Network Approach
(1) A non-linear approach used for designing traffic applications.

(2) A non-linear mapping between a set of input and output. For example, the approach can associate patterns in traffic data with various traffic conditions. It offers an advantage over conventional incident detection algorithms in that no mathematical model of traffic operation or incident detection process is required, thus eliminating the imperfection in model formulation.

Nighttime
The hours of darkness, taken as the time period from one-half hour before sunset to one-half hour after sunrise.

Nighttime Short Duration Provisions
Provisions required for nighttime short duration work, even though one or more may be shown as optional for the daytime short duration operations illustrated in the typical layouts of Book 7. For nighttime work of any duration, traffic garments meeting OHSA requirements for nighttime work must be used.

Non-conflicting Phases (Traffic Signal)
Two or more traffic phases which will not be in conflict with each other if operated concurrently.

Non-recurring Congestion
Congestion caused by a random event (e.g., incident, maintenance activity, special event, etc.), which has the effect of reducing capacity on a specific section of freeway.

No Parking
See Parking and Parking Restriction.

Normal Regulatory Posted Speed
The regulatory maximum speed posted on a highway under normal conditions, that is, when no construction zone or work activity is present. Guideline provisions required in Book 7 are based on Normal Regulatory Posted Speed, not on temporarily reduced construction zone regulatory or advisory speeds.

No Standing
The prohibition of the halting of a vehicle whether occupied or not, except for the purpose of and while actually engaged in the receiving or discharging of passengers.

No Stopping
The prohibition of the halting of a vehicle, even temporarily, whether occupied or not, except where necessary to avoid conflict with other vehicles, or in compliance with the directions of a police officer or Traffic Control Signal.

NTCIP
National Transportation Communications for ITS Protocol.

Numbered Highway
A highway to which a number has been allotted for the purpose of identification throughout its entire length.

0

Object Marker
A traffic sign mounted temporarily or permanently on an obstruction, within or adjacent to the roadway, to make the obstruction as highly visible as possible.

Occupancy
Percentage of time a given section of roadway is occupied by vehicles.

Official Sign
Any sign approved by the Ministry of Transportation Ontario.

Off-peak Period
The period of time, usually outside of the morning and afternoon Peak Periods. If there is a Midday Peak with traffic volumes equalling or approaching those in the A.M. or P.M. Peak Periods, then this Midday Peak should be excluded from the off-peak period.

Off Ramp
That part of an interchange connecting a Deceleration Lane to a crossroad.

Off-road Bikeway
A bicycle path which is not immediately adjacent to a roadway.

Offset (Traffic Signal)
The number of seconds or percent of cycle length that a defined time-reference point (the "yield point", normally the start of main street green) at the traffic control signal occurs after the time-reference point of a master controller or of an adjacent traffic control signal.

OHBDC
Ontario Highway Bridge Design Code.

Older Driver
A driver aged 55 years or older.

On Ramp
That part of an interchange connecting a crossroad to an Acceleration Lane leading onto a Major Road.

On-street Bikeway
Any bikeway within the roadway.

On-street Parking
The use of vehicle parking on the roadway surface or on the adjacent shoulder.

OPAC
Optimization Policies for Adaptive Control.

Operating Cost
Non-capital costs associated with operating and maintaining a transit system, including labour, fuel, administrative and maintenance.

Operating Speed
The speed at which the majority of vehicles are travelling, typically the 85th Percentile, regardless of the speed limit.

Operator (ATMS)
Person at the Traffic Operation Centre assigned to manage traffic flow on the highway network using system components and functions.

Opposing Traffic (Traffic Signal)
Traffic progressing in the opposite direction to the traffic being considered on a roadway.

OPS
Ontario Provincial Standards.

OTDR
Optical Time Domain Reflectometer.

Overall Travel Time
The time of travel, including stops and delays except those off the travelled way.

Overhead Sign
A Traffic Sign mounted above the Roadway, usually with 4.6 m to 5.3 m of vertical clearance and preferably located over the lane or lanes to which the sign applies.

Overlap (Traffic Signal)
A right-of-way indication that is derived from the service of two or more traffic phases.

Overpass
A Grade Separation where the travel way in question passes over the other travel way.

Oversize Sign
A Traffic Sign with greater proportional dimensions than the minimum dimensions specified in this Manual. Such signs are generally required on higher speed highways, or on other highways in special cases.

Pace Range
The range of speeds for a defined interval (an interval of, for example, 15 or 20 km/h) that contains the largest number of vehicles in a speed study sample.

Para-transit
A transit system for those with difficulty accessing a conventional transit system. Para-transit vehicles are often lift- or ramp-equipped to permit access by persons in wheelchairs.

Park & Ride
An access mode to transit in which patrons drive private automobiles or ride bicycles to a transit station, stop, or carpool/vanpool waiting area and park the vehicle in the area provided for that purpose. They then ride the transit system or take a car or vanpool to their destination. (Also Park 'n' Ride.)

Park & Ride Lot
Designated parking area for automobile drivers who then board transit vehicles from these locations.

Parking
The stationary storage or leaving of a vehicle unoccupied or unattended.

Parking Control Sign
A sign which identifies the times of day and days of week parking, stopping or standing restrictions are in place on the section of road adjacent to the sign.

Parking Restriction
A limitation which prevents vehicles from being parked in specific locations, at specific times, or for specific types of vehicle. Most often used to control on-street parking.

Parking (and Stopping) Signs
A Traffic Sign of the regulatory type which informs drivers of the parking and stopping regulations in effect on facilities where such signs are erected.

Parking Space Marking
Markings intended to inform drivers where they are permitted to park.

Park-way
The classic definition of a parkway is a Freeway on which trucks are prohibited. However, the term has been applied to such a variety of road types, that a commonly agreed definition of parkway is hardly possible. These other types of roads include-.

(1) a Freeway on which trucks are permitted;

(2) an Expressway with At-grade Intersections, with or without truck prohibitions-,

(3) a Two-lane Highway with partial control of access, with truck prohibitions.

Partial Lane Shift
The temporary, partial shifting of travel lanes by demarcating them through use of cones or barrels, so that the lanes are squeezed while still maintaining usable lane widths of at least 3 m in each lane. See also Narrow Lanes and Roadside Diversions.

Passage Detection (Traffic Signal)
The ability of a vehicle Detector to detect the passage of a vehicle moving through the detection zone and to ignore the presence of a vehicle stopped within the detection zone.

Passage Time (Traffic Signal)
(1) See Unit Extension Time.

(2) The time allowed for a vehicle to travel at a selected speed from the detector to the Stop Bar.

Passenger
Any occupant of a Motor Vehicle who is not a Driver.

Passenger Car Equivalence
The representation of larger vehicles, such as trucks and buses, as equal to a quantity of passenger cars for use in Level of Service and Capacity analyses. The magnitude of the equivalency is dependent upon vehicle size and weight, vehicle operating characteristics, vehicle speeds, and roadway characteristics such as gradient.

Passing Sight Distance
The length of highway required for a vehicle to execute a normal passing manoeuvre as related to design conditions and design speed.

Pattern (Traffic Signal)
A unique set of coordination parameters including Cycle Length, split values, Offsets and sequence of Intervals.

Pavement
That part of the Roadway having a constructed hard surface for the facilitation of vehicular movement.

Pavement Marking
A coloured marking applied to the pavement to provide drivers with roadway alignment information.

Peak Hour
The one hour each day when traffic volumes are at their highest on a given road.

Peak Period
The one or more periods each day, usually consisting of two or three hours, when traffic volumes are at their highest on a given road, usually corresponding to a morning "to work' period and an afternoon "from work" period.

Pedestal (Traffic Signal)
Ground-mounted enclosure for communication or a support for a Controller Cabinet.

Pedestrian
Any person who is not in or upon a vehicle, motorized or otherwise propelled, or riding upon an animal.

Pedestrian Clearance Interval (Traffic Signal)
The time in seconds during which the orange hand is flashed, starting after a walking pedestrian indication and ending before conflicting vehicles receive a green indication (may include the vehicle amber time).

Pedestrian Crossover
Any portion of a Roadway, designated by by-law of a municipality, at an intersection or elsewhere, distinctly indicated for pedestrian crossing by signs on the highway and lines or other markings on the surface of the roadway as prescribed by the regulation and the HTA, with associated signs Ra-4, Ra-4t, Ra-10 and Ra-11.

Pedestrian Crosswalk
Any portion of the Roadway, at an Intersection or elsewhere, distinctly indicated for pedestrian crossing by appropriate pavement markings and/or signs, or by the projections of the lateral lines of the sidewalk on opposite sides of the road.

Pedestrian Facility
A facility where pedestrians are controlled and protected from other road users.

Pedestrian Mall
A Pedestrian Facility from which motor vehicles are excluded, except at crossroads.

Pedestrian Sign
See School and Pedestrian Signs.

Pedestrian Signal (Traffic Signal)
A Traffic Signal head or indication showing either a white walking pedestrian on a black background (when pedestrians are permitted to cross) or an orange hand on a black background (when pedestrians are not permitted to cross, if continuous, or are not permitted to start crossing, if flashing).

Pedestrian Walkway
A continuous way designated for pedestrians and separated from the through lanes for motor vehicles by space or a barrier.

People Mover
An automated transportation system (e.g., continuous belt system, moving sidewalk or automated guideway) that provides short haul collection distribution service, usually in a major activity centre.

Perception-reaction Time
The time required to make a decision, after reading or encountering a traffic control device, and initiate a manoeuvre if required.

Permissive
Refers to areas where a driver is permitted to travel.

Permissive Symbol
An annular (circular) green band used on a sign to signify that whatever is depicted within the symbol is permitted.

Personal Digital Assistant
Computer products with radio frequency communication that allow users to obtain various types of travel information.

PGIS (Parking Guidance and Information Systems)
This system works by cyclically acquiring data from a number of connected parking facilities (e.g. the number of free spaces and the number of entering/exiting vehicles). This data is the basis for proper functioning and acceptance of the guidance system.

Phase (Traffic Signal)
A part of a cycle where one or more traffic movements receive a green indication at the same time. Phase time is the time required from the start to the finish of the phase including Amber and All-red Interval times.

Phase Sequence (Traffic Signal)
A predetermined order in which the phases of a cycle occur.

Phase Skip (Traffic Signal)
A function used to provide omission of a phase in the absence of actuation on that phase.

PHF
Peak Hour Factor.

PHV
Peak Hourly Volume.

Physically Separated Pedestrian Facility
A pedestrian facility which is separated from a roadway by space or barrier and from which motor vehicles are excluded.

Plan (Traffic Calming)
A formulated and sufficiently detailed description of how an objective or number of objectives are to be accomplished. A Traffic Calming plan typically describes measures to be used, where they are to be located, in what order and at what times they will be implemented, and how the costs of the measures will be funded.

Plan (Traffic Signal)
A unique set of timing values, intervals used and sequence of intervals that is stored in or sent to a Controller Unit. Different plans may be used for time of day, time of week, special events and so on or may be traffic-responsive as determined by detector actuation.

P.M. Peak Hour
The one hour each afternoon when traffic volumes are at their highest.

RM. Peak Period
The period in the afternoon (usually two to three hours) when traffic volumes are at their highest.

Poll (Traffic Signal)
An enquiry message sent from a Master Controller to a Slave Controller on a regularly timed basis to solicit the status of the slave.

Portable Lane Control Signal
See Portable Traffic Control Signal.

Portable Traffic Control Signal
A portable traffic control signal may be used as an alternative to Traffic Control Persons and such signals are used only to stop vehicles intermittently when traffic must use a single lane in situations where the roadway is normally a two-way operation. Portable traffic control signals must comply in all respects with Regulation 606 of the Highway Traffic Act. (R.S.O. 1990), where they are referred to as Portable Lane Control Signals. See Book 7, and Book 12.

Portable Variable Message Signs (PVMS)
Portable signs typically have the same functionality and basic design as fixed location Variable Message Signs and can be comprised of discrete characters or full matrix arrangements.

Positive Guidance
Provision to road users of the information they need to avoid hazards, when and where they need it, in a form they can best use it. See Book I c (Positive Guidance Toolkit).

Posted Advisory Speed
The maximum advisory speed as indicated by appropriate Warning or Temporary Conditions Signs.

Posted Speed Zone
A section of highway upon which the maximum speed is indicated by appropriate Regulatory Signs.

Post-mounted Delineator
A delineation device that consists of Retroreflective Material mounted on a 1.2 m post to provide long range information on roadway alignment.

Pre-emption (Traffic Signal)
The transfer of the normal control of signals to a special signal control mode for the purpose of servicing railway crossings, emergency vehicle passage, transit vehicle passage and other special tasks, the control of which requires terminating normal traffic control to provide priority needs of the special task.

Pre-emptor (Traffic Signal)
A device or program/routine which provides pre-emption.

Pre-engineering and Engineering Activities
Activities carried out in preparation for, during, or after completion of a construction project (e.g., surveying, geotechnical sampling or testing, pre-construction inspection). For purposes of Book 7 traffic control, pre-engineering activities are considered part of construction work activities.

Pre-marking
A preliminary marking applied to the pavement to guide the operator of a Striper in applying the final Pavement Markings.

Prescribed Sign
The Highway Traffic Act (HTA, Ontario), Section 182 (R.S.O. 1990), provides for the regulation of various signs, their type and location on the roadway. The criteria and specifications for application, dimensions, location and orientation are prescribed and illustrated under Regulations 615, 608, 581, 699 (R.R.0 1990) and are indicated as such in this Manual. Signs erected in accordance with the Regulations, and pursuant to the Highway Traffic Act, are enforceable under various provisions of the Act. Enforcement is permitted under the particular section under the authority of which a prescribed sign may be erected to indicate a traffic regulation, or HTA Section 182 (R.S.O. 1990), which requires obedience to prescribed signs.

Presence Detection (Traffic Signal)
The ability of a vehicle Detector to sense that a vehicle, whether moving or stopped, has appeared in its field.

Pre-timed (Traffic Signal)
A Controller Unit mode of operation of Traffic Control Signals with predetermined fixed cycle lengths, fixed interval duration and fixed interval sequences.

Private Roadway
Any roadway owned and maintained by an individual, group of individuals, or a corporation, with restricted public use.

Probe Vehicles
Vehicles which act as moving sensors (or probes) to provide information about traffic conditions.

Progression (Traffic Signal)
(1) The time relationship between adjacent signals on a roadway which permits a platoon of vehicles to proceed through the signals at a planned rate of speed-,

(2) The act of various Controller Units providing specific green indications in accordance with a time schedule to permit continuous operation of groups (platoons) of vehicles along the road at a planned speed.

Provincial Highway
Any public highway under the jurisdiction of the Ministry of Transportation of Ontario (MTO). See King's Highway.

Public Roadway
Any roadway under the jurisdiction of and maintained by a public authority and open to public travel.

Public Transportation
Transportation by bus, rail, or other conveyance, either publicly or privately owned, which provides to the public general or special service on a regular and continuing basis. Also known as "mass transportation," "mass transit" and "transit".

Public Way
A sidewalk, street, highway, square, or other open space to which the public has access, as of right or by invitation, either express or implied.

PVMS
Portable Variable Message Sign.

PXO
Pedestrian Crossover.