Activity Area - Area of a temporary traffic control zone comprised of the buffer space and the work space usually separated from traffic flow by channelizing devices or barrier located parallel to the travel lanes.
Buffer Space - Area that separates traffic flow from the work space. Buffer spaces must remain clear of equipment, vehicles, workers, and materials. The length of longitudinal buffer spaces is defined as distance E on PATA figures and may be increased for downgrades or other conditions that affect stopping sight distance.
- Longitudinal buffer space is located in advance of and after the work space.
- Lateral buffer space is located between flowing traffic and the activity area.
Complex Condition (Temporary/Portable Traffic Signals) - A condition where driveways and/or side roads are located between the temporary signal installation locations. Additional signal installations or flaggers are required in additional to those shown on any PATA 700 series drawing.
Conventional Highway - Any highway other than a freeway or expressway.
Emergency Work - Emergencies may arise where it will be necessary to begin work even though all of the specific traffic control provisions may not be satisfied. In these cases all available safety measures shall be taken and the work zone shall be brought into compliance with this publication as soon as possible.
Expressway - A divided arterial highway for through traffic with partial control of access and generally with grade separations at major intersections.
Freeway - A highway to which the only means of ingress and egress is by interchange ramps.
Highway - The entire width between the boundary lines of every way publicly maintained when any part thereof is open to the use of the public for purposes of vehicular travel.
Long-Term Stationary Operation - Work that occupies a location for a period of more than 24 hours.
Mobile Operation - An operation in the vehicular travel lane, or along the roadway, that proceeds in the direction of normal traffic flow. Every component of the operation, excluding advanced warning signs and flagger locations, must proceed in the direction of normal traffic flow at a rate of at least 100' for each 15 minute interval for the entire length and duration of the operation. This distance and time threshold must be met for the entire length and duration of the operation in order to utilize a PATA 300 or 600 Series drawing. The duration of a Mobile operation shall not exceed 24 hours.
Non-Complex Condition (Temporary/Portable Traffic Signals) - A condition where driveways and/or side roads do not exist in the temporary traffic control zone utilizing temporary traffic signals. PATA 700 series drawings can be implemented and run automatically exactly as shown without flagger assistance or additional signals.
Numbered Traffic Route - A highway that has been assigned an Interstate, United States, or Pennsylvania Route Number, consisting of one, two, or three digits, sometimes with an additional designation such as business route, truck route, or other similar designation.
PATA (Pennsylvania Typical Application) - Drawings within this publication that depict temporary traffic control conditions.
Portable Sign Post - Rigid device with steel posts for mounting temporary traffic control devices where minimum mounting heights of at least 5’ are required. Refer to Publication 111, Traffic Control - Pavement Markings and Signing Standards TC-8717, for details.
Portable Sign Support - A folding, collapsible, or telescoping device for posting temporary traffic control devices where minimum mounting heights of 1’ are acceptable.
Roadway - That portion of a highway improved, designed, or ordinarily used for vehicular travel, exclusive of the sidewalk, berm, or shoulder.
Roll Ahead Space - Space provided between the shadow vehicle and the work space in a closed lane. This space shall be clear of equipment, vehicles, workers, and materials. Shown as distance H on PATA drawings.
Rural Highway - A type of roadway normally characterized by lower volumes, higher speeds, and fewer conflicts with turning vehicles and pedestrians. Rural highways often have speed limits greater than 35 MPH, but are not freeways or expressways.
Shadow Vehicle - A vehicle positioned within the activity in advance of the work space and work vehicles. The primary purpose of the shadow vehicle is to provide advance information to approaching drivers while protecting workers and work vehicles. Any vehicle can be used as a shadow vehicle as long as it is equipped with a flashing, oscillating, or revolving yellow light which is visible from any direction (360° visibility) and is not being used as a work vehicle. The yellow light must be activated within an active work zone.
Short-Term Stationary Operation - An operation that will occupy a location for up to 24 hours. The work zone will have stationary beginning and ending points. Work activity may move freely within these limits.
Shoulder - The part of a highway adjacent to the roadway which has a surface constructed with the same or similar material as the roadway. Shoulder width is measured from the center of the painted edge line to the outside edge of pavement, concrete, or finished surface.
Sidewalk - That portion of a street between curb lines, or the lateral lines of a roadway, and the adjacent property lines, intended for use by pedestrians. A 48" minimum usable width must be maintained.
Taper - A series of channelizing devices and/or paint lines installed for the purpose of moving traffic out of or into the normal path. Various taper types have differing minimum lengths, most of which are based upon an 'L' distance. The formula to determine distance L is shown on the corresponding PATA notes page. It should be noted that the taper length is a distance per lane; so if a single taper covers two lanes, the total taper length will be double the calculated or minimum distance.
- Merging Taper - Used when drivers in multiple lanes are required to merge into a common road space. Minimum length is L.
- Shifting Taper - Used when a lateral shift is needed. Minimum length required is distance 1/2 L, unless traffic is approaching a one -lane, two-way condition; in this case the minimum length is 50'.
- Shoulder Taper - Required when closing a paved shoulder having a width of 8' or more; optional in other conditions. Minimum length is 1/3 L, unless traffic is approaching a one-lane, two-way condition; in this case the minimum length is 25'.
- Downstream Taper - Used in the termination area to provide a visual cue to the driver that access is available back into the original lane or path that was closed. Minimum distance is 50' per lane.
Temporary Traffic Control Zone - An area of a highway where road user conditions are changed because of a work zone or incident by the use of temporary traffic control devices, flaggers, uniformed law enforcement officers, or other authorized personnel.
Truck Mounted Attenuators (TMA) - Shall be mandatory for placement on shadow vehicles utilized on freeways and expressways, including exit and entrance ramps. The TMA is optional on all other highways. When a TMA is used, the weight of the shadow vehicle must be greater than the minimum weight specified by the TMA manufacturer.
Urban Area or Urban Highway - A type of roadway normally characterized by wide ranges of traffic volumes, frequent intersections and driveways, significant pedestrian traffic, speed limits of 35 MPH and below, and most often parking along one or both sides of the roadway.
Warning Lights - Yellow lights that operate in steady burn or flashing mode. Warning lights on authorized vehicles may flash or revolve. Type A, B, C, and D warning lights are portable, powered, yellow, lens-directed enclosed lights.
Worker - A person on foot whose duties place him or her within the right-of-way of a highway, such as highway construction and maintenance forces, survey crews, utility crews, responders to incidents, and law enforcement personnel when directing traffic, investigating crashes, and handling lane closures, obstructed roadways, and disasters within the right-of-way of a highway.
Work Space - Area within a temporary traffic control zone that is set aside for workers, work vehicles, equipment, and material storage.
Work Vehicle - A vehicle available for use by workers within an activity area. All work vehicles shall be located outside of the buffer space and roll ahead space for shadow vehicles. Work vehicles being used in an active work zone must utilize the flashing, oscillating, or revolving yellow lights which are visible from any direction (360° visibility).
Work Zone - The area of a highway where construction, maintenance, or utility work activities are being conducted, and in which traffic control devices are required in accordance with Title 67, Chapter 212.