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Glossary of Terms

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A.D.A.: American with Disabilities Act

A.N.S.I.: American National Standards Institute

A.S.T.M.: American Society of Testing & Materials

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Caulk: A silicone or latex base sealant used over windows, doors, glass in doors, and in siding seams over windows and doors to protect against leakage.

Closer: Hardware mounted on a door, usually at top of door that through the use of hydraulic pressure, closes a door automatically.

H.C.: Hollow core. Type of door that is hollow in the center of the door. Typically wood construction.

H.M.: Hollow metal. Type of door that is made out of metal sheets with a hollow core.

Panic Device: Hardware mounted on a door, usually waist high, that allows you to open a door from the inside by pushing on a bar.

S.C.: Solid Core. Type of door that is solid in the center. More expensive than hollow core. Adds sound and sometimes fire rating to door.

Rated Door: Term for the fire rating assign to a certain door. Doors in fire rated walls or fire separations require rated doors. Rating is a value associated with how long a fire will take to burn through the structure. Ratings range from 20 minutes, to 1 hour, 1-1/2 hours, 2 hours, etc.

V.P.: Vision Panel. Term for the glass in doors. Usually 10"x 10"or 5"x 20".

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AC: Alternating current (or air conditioning)

Amps: Amperes, the intensity of electrical current produced through resistance of device, the rate of flow of electricity through a circuit

AWG: American Wire Gauge, refers to standard wire sizes.

Breaker: Circuit breaker. Overload protection device. Electrical device used to open and close electrical circuit by manual means or open circuit automatically on predetermined overload current. Example: 20 amp breaker will trip open the circuit when detects more than 20 amp draw on circuit wiring.

Breaker- Double Pole: Device to open, close, protect 240 volt circuits.

Breaker- Main: Device to open, close, protect all breakers in panel.

Breaker- Single Pole: Device to open, close, protect 120 volt circuits.

BX: Type of electrical conduit, refers to metal jacket around wires. One step up from romex.

Circuit: The wiring and devices to which electricity is supplied from the breaker panel.

Conduit: A tube or trough for receiving and protecting electric wires.

Disconnect: A switch device with which to disconnect an electrical circuit. Although not fused (protective device to protect from over current) must be sized to circuit capacity.

Egress Lighting: Emergency lighting that lights the exit in a building during power outages. Typically wall mounted, battery backup lights.

GFI: Ground Fault Interrupter. A special sensitive breaker or receptacle used in a circuit where water may come in contact with equipment, such as in a bathroom, kitchen, or exterior receptacle. The purpose is to protect personnel and equipment from shock.

Ground: An electrical circuit attached to earth ground. Can be a bare copper or sheathed in green wire.

Homerun: Term for the electrical circuit wire that goes from the last electrical device back to the electrical panel.

J-Box: Junction Box. Box for joining or splicing wires. Can be metal or plastic. Typically have a J-box behind each electrical device or at a point where two separate wires must be joined.

Light-Diffused Fluorescent: Fluorescent light fixture with plastic light cover that diffuses the light.

Light- Fluorescent Strip: Fluorescent light fixture with exposed bulbs.

Load Center: Another name for electrical subpanel. Typical designation is 100 a. 120/240, which mean the panel is rated for 100 amperes of incoming current at 120/240 volts.

MC Cable: Type of electrical wire that comes in its own metal sheathing. Similar to BX cable but one step up from BX cable. Sometimes allowed to be used where code requires conduit but not BX cable.

M.D.P.: Main Distribution Panel. The point where electrical service enters the trailer. The panel for controlling electrical feeds to the individual subpanels in trailers. Usually provided by owner or others, not part of trailer.

N.E.C.: National Electric Code

Phase: Electrical service consists of either single phase or three phase. Refers to the number of wires that provide current to a device. Normal trailer power is 240 volt single phase service with (2) power, (1) neutral, and (1) ground wire.

Pull Wire: Wire or string placed in a wall or conduit that allows you to pull electrical wires through wall or conduit at a later time.

Romex: Typical trailer wiring consisting of three wires in a non- metallic covering used to provide electrical current from subpanels to electrical devices such as receptacles, light switches, lights.

Rough-in: Term for providing a J-box and pull wire to an accessible location for later use. Typcally done for telephone locations. Does not include wire, conduit, or devices.

Service Entrance: Conduit connected to panel box designed for incoming electrical service to come from outside into panel.

.019 Aluminum: Standard aluminum exterior siding with baked on enamel finish. .019 refers to gauge of metal or thickness.

2 x 3: Wood lumber with a measurement of 1-1/2"x 2-1/2”. Comes with designations such as SYP (Southern Yellow Pine), SPF (Pine Fir), and #2 which designate the quality level of the wood. The higher the number the better the wood.

2 x 4: Wood lumber with a measurement of 1-1/2"x 3-1/2”. Comes with designations such as SYP (Southern Yellow Pine), SPF (Pine Fir), and #2 which designate the quality level of the wood. The higher the number the better the wood.

2 x 6: Wood lumber with a measurement of 1-1/2"x 5-1/2”. Comes with designations such as SYP (Southern Yellow Pine), SPF (Pine Fir), and #2 which designate the quality level of the wood. The higher the number the better the wood.

Belt Rails: 1-1/2"x _"lumber running horizontally in the wall used as bracing and blocking to screw exterior siding to.

Caulk: A silicone or latex base sealant used over windows, doors, glass in doors, and in siding seams over windows and doors to protect against leakage.

Dura Temp: Type of T-1-11 siding. Has pre-finished exterior finish that can be painted.

Exterior Finish: Finish applied to exterior of exterior walls (aluminum, T-1-11, steel siding, stucco, vinyl siding)

Insulation: Material used in a cavity to prevent loss of heat or cooling from structure. Standard material is fiberglass bat. Different type covering include un-faced(no covering, Kraft faced(paper covering), foil faced(foil covering).

Plate: Refers to a continuous horizontal framing member on top or bottom of wall studs. Can be single plate or double plate.

Putty Tape: A 1/8"x 1"roll type putty used for sealing windows and doors at the time of installation.

Sheathing: Layer of flat covering, typically plywood, that spans between wall studs.

Skirting: Exterior finish around bottom of trailer(from ground to underside of trailer) that is site installed after unit is blocked and leveled. Involves building a wood framed wall to support skirt.

T-1-11: Exterior wood siding. Comes in _"to 5/8"thickness, 4 foot by 8 foot sheets, with horizontal grooves at 4 inch to 8 inch spacing. Can be painted or stained to any color.

Thermopylae: 1/8"thick wall sheathing, foil covered. Typically used under the aluminum siding for strength and moisture protection.

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Auger Footing: Term for round hole drilled in ground and filled to top of hole with concrete.

Block & Level: Term for truck setting the modular building in place, and leveling the floor by placing CMU or concrete block under frame of unit. Does not include cranes, anchors, skirting.

C.M.U.: Concrete Masonry Unit, refers to concrete block used to block up trailers.

Footings: Part of foundation that is below ground level that transfers the load or weight of trailer to ground. Typically constructed out of concrete.

Piers: Part of foundation that is above ground level that transfers the load or weight of trailer to ground. Standard pier is a single loose stack CMU or concrete block. Piers can also be mortared in place CMU or concrete block, or poured concrete.

Tie-Downs: Term for device that is drilled or driven into ground then attached to trailer. Prevents trailer from being knocked over by wind.

Skirting: Exterior finish around bottom of trailer(from ground to underside of trailer) that is site installed after unit is blocked and leveled. Involves building a wood framed wall to support skirt.

Axle Brake: A 6,000 lbs capacity axle with electric brakes, it can be 55-1/2”, 75-1/2”, or 88-1/2"wide.

Axle Idler: A 6,000 lbs capacity axle without brakes, it can be 55-1/2”, 75-1/2”, or 88-1/2"wide.

Brake Wire: Wiring to connect brake axles to the towing vehicle.

Coupler: The part of a hitch which connects to a towing ball on the towing vehicle. Typically a 2-5/16 inch ball size.

Cross member: The part of the steel chassis which connects the main beams and supports the floor.

Header: The cross member of an outrigger steel frame located at the front or rear of the chassis. The shape of the member can be “C"or “Z"channel.

Hitch: The triangular part of the frame located at the front of the chassis on which the coupler and jack are attached. Hitch is constructed of steel I beam, and is removable on larger units such as 10 and 12 wides. Approximately 4 feet long and is included in the length of the trailer when referenced as a size, i.e., a 64 foot model unit is box size of 60 feet, and a four foot hitch.

I-Beam: Steel beam, shaped like the letter I. Used in frame for structural support. Ranges in height from 6"to 14”.

Jack: Adjustable metal bar located at front of hitch that acts as a mechanical lifting device to raise and lower the front end of the trailer to allow trucks to unhook from hitch without the hitch and trailer falling to the ground.

Outrigger: Frame style, steel chassis on which the modular buildings floor, walls, and roof are built. Uses triangular shaped members to transfer exterior wall and roof loads to an interior main frame. Less expensive than Perimeter Frame. In trailers bigger than a single wide, requires more blocking points than a Perimeter Frame.

Perimeter: Frame style, steel chassis using a main I-beam frame around perimeter of unit. It requires fewer blocking points than an Outrigger Frame.

Pintail Eye: A type of coupler at the front of the hitch. Shaped like a large donut. Used on hitches attached to heavy trailers. Not all truckers can handle pintel eye hitches.

Tie Downs: Anchors that are tied to trailer to prevent wind from blowing over unit. Anchor is tied to metal strap that is looped over chassis or attached to hurricane strap. Types of anchors are augered anchor (for dirt), or drive anchors (for rock).

2 x 6: Wood lumber with a measurement of 1-1/2"x 5-1/2”. Comes with designations such as SYP (Southern Yellow Pine), SPF (Pine Fir), and #2 which designate the quality level of the wood. The higher the number the better the wood.

Bottom Board: Covering on bottom of floor frame. Provides moisture and vermin barrier between ground and floor, and supports insulation. Types of bottom board are Simplex Paper(cheaper) and galvanized metal(more expensive).

Decking: Floor sheathing over top of floor joists or cross-members. Usually 5/8 inch thick, 5 ply, under lament grade. Other types are T&G, _ inch.

Floor Finish: Finish applied to floor decking (VCT, carpet, vinyl roll goods, ceramic).

Galvanized Metal: .040 gauge steel rolls with galvanized coating. Used for roofs or bottom boards on floors. Metal comes in rolls 12 wide with crimped seams every 8 feet.

Insulation: Material used in a cavity to prevent loss of heat or cooling from structure. Standard material is fiberglass batt. Different type covering include unfaced(no covering, kraft faced(paper covering), foil faced(foil covering).

Joists (Floor): Structural member which supports floor decking, usually wood 2 x 6's or 2 x 8's. Supported by floor frame or chassis.

Roll Goods: Type of floor finish. Comes in rolls. Less expensive than tile, but does not wear as well.

“R"Value: The resistance to heat flow. A measure of how effective the insulation is. The higher the “R"value, the more effective the insulation.

Simplex Paper: Type of bottom board. Paper impregnated with asphalt coating to provide moisture and vermin barrier.

T & G: Tongue and Groove. Plywood with sides shaped that the tongue side slips into the groove side giving additional support to plywood. Allows plywood to span between floor joists with less spongy feeling.

VCT: Vinyl Composition Tile. Type of floor covering. 12 inch by 12 inch tiles that are used in areas that have more foot traffic and such as entrance areas, rest room.

N.F.P.A.: National Fire Protection Association

Life Safety: Refers to N.F.P.A. 101 – Life Safety Code

U.F.C.: Uniform Fire Code

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ACCESS RIGHT: The privileges accorded a user for reading, writing, deleting, updating and executing files on a disk. Access rights are stated as 'no access', 'read only' and 'read/write'.

ADDRESS MATCHING: A mechanism for relating two files using address as the relate item. Geographic coordinates and attributes can be transferred from one address to the other. For example, a data file containing student addresses can be matched to a street coverage that contains addresses creating a point coverage of where the students live.

ALLOCATION: The process of assigning arcs in a network to the closest center until the maximum impedance or resource capacity of the center is reached.

ANNOTATION: 1. Descriptive text used to label coverage features. It is used for display, not for analysis. 2. One of the feature classes in a coverage used to label other features. Information stored for annotation includes a text string, the location at which it is displayed, and a text symbol (color, font, size, etc.) for display.

ARC: 1. An ordered string of vertices (x,y coordinate pairs) that begin at one location and end at another. Connecting the arc's vertices creates a line. The vertices at each endpoint of an arc are called nodes. 2. A coverage feature class used to represent linear features and polygon boundaries. One line feature can contain many arcs. Arcs are topologically linked to nodes (arc-node topology) and to polygons (polygon-arc topology). The descriptive attributes of arcs are stored in the arc attribute table (AAT).

ATTRIBUTE: 1. A characteristic of a geographic feature described by numbers, characters, images and CAD drawings, typically stored in tabular format and linked to the feature by a user-assigned identifier (e.g., the attributes of a well might include depth and gallons per minute). 2. A column in a database table. See also item.

ATTRIBUTE TABLE: An INFO or other tabular file containing rows and columns. In ArcInfo, attribute tables are associated with a class of geographic features, such as wells or roads. Each row represents a geographic feature. Each column represents one attribute of a feature, with the same column representing the same attribute in each row.

BUFFER: A zone of a specified distance around coverage features. Both constant- and variable-width buffers can be generated for a set of coverage features based on each feature's attribute values. The resulting buffer zones form polygons-areas that are either inside or outside the specified buffer distance from each feature. Buffers are useful for proximity analysis (e.g., find all stream segments within 300 feet of a proposed logging area).

CALLIBRATION: The process of choosing attribute values and computational parameters so that a model properly represents the real-world situation being analyzed.

CLIENT/SERVER: A software system is said to have a client/server architecture when there is a central process (server) which accepts requests from multiple user processes (clients).

CLIP: The spatial extraction of those features from one coverage that reside entirely within a boundary defined by features in another coverage (called the clip coverage)-clipping works much like a cookie cutter.

COGO: Abbreviation of the term COordinate GeOmetry. Land surveyors use COGO functions to enter survey data, to calculate precise locations and boundaries, to define curves, and so on.

COORDINATE: A set of numbers that designate location in a given reference system, such as x,y in a planar coordinate system or an x,y,z in a three-dimensional coordinate system. Coordinates represent locations on the Earth's surface relative to other locations.

COVERAGE: 1. A digital version of a map forming the basic unit of vector data storage in ArcInfo. A coverage stores geographic features as primary features (such as arcs, nodes, polygons, and label points) and secondary features (such as tics, map extent, links, and annotation). Associated feature attribute tables describe and store attributes of the geographic features. 2. A set of thematically associated data considered as a unit. A coverage usually represents a single theme such as soils, streams, roads, or land use.

DATABASE MANAGEMENT SYSTEM (DBMS): A set of computer programs for organizing the information in a database. A DBMS supports the structuring of the database in a standard format and provides tools for data input, verification, storage, retrieval, query, and manipulation.

DATUM: A set of parameters and control points used to accurately define the three-dimensional shape of the Earth (e.g., as a spheroid). The datum is the basis for a planar coordinate system. For example, the North American Datum for 1983 (NAD83) is the datum for map projections and coordinates within the United States and throughout North America.

DIGITIZE: 1. To encode geographic features in digital form as x,y coordinates. 2. The process of using a digitizer to encode the locations of geographic features by converting their map positions to a series of x,y coordinates stored in computer files. Pushing a digitizer button records an x,y coordinate. A digitized line is created by recording a series of x,y coordinates.

DISSOLVE: The process of removing boundaries between adjacent polygons that have the same values for a specified attribute.

DOMAIN: In a database, the set of allowed values for a table column, for example all positive integers.

EDGE MATCHING: An editing procedure to ensure that all features that cross adjacent map sheets have the same edge locations.

FEATURE ATTRIBUTE TABLE: A table used to store attribute information for a specific coverage feature class. ArcInfo maintains the first several items of these tables. Feature attribute tables supported for coverages include:

FEATURE CLASS: A classification describing the format of geographic features and supporting data in a coverage. Coverage feature classes for representing geographic features include point, arc, node, route-system, route, section, polygon and region. One or more coverage features are used to model geographic features; for example, arcs and nodes can be used to model linear features such as street centerlines. The tic, annotation, link, and boundary feature classes provide supporting data for coverage data management and viewing.

FUZZY TOLERANCE: The fuzzy tolerance is an extremely small distance used to resolve inexact intersection locations due to limited arithmetic precision of computers. It defines the resolution of a coverage resulting from the CLEAN operation or a topological overlay operation such as UNION, INTERSECT, or CLIP.

GEOCODE: The process of identifying the coordinates of a location given its address.

GIS: Geographic Information System. An organized collection of computer hardware, software, geographic data, and personnel designed to efficiently capture, store, update, manipulate, analyze, and display all forms of geographically referenced information.

GRAPHICAL USER INTERFACE (GUI): A graphical method of controlling how a user interacts with a computer to perform various tasks. Instead of issuing commands at a prompt, the user performs desired tasks by using a mouse to choose from 'a dashboard' of options presented on the display screen. These are in the form of pictorial buttons (icons) and lists. Some GUI tools are dynamic and the user must manipulate a graphical object on the screen to invoke a function; for example, moving a slider bar to set a parameter value (e.g., setting the scale of a map).

GRID: A geographic data model representing information as an array of equally sized square cells arranged in rows and columns. Each grid cell is referenced by its geographic x,y location.

LAN: Local area network. Computer data communications technology that connects computers at the same site. Computers and terminals on a LAN can freely share data and peripheral devices, such as printers and plotters. LANs are composed of cabling and special data communications hardware and software.

LIBRARIAN: A set of software tools to manage and access large geographic data sets in a map library. LIBRARIAN commands create and define a map library, move data in and out of a library, query the data in a map library, and display the results of a query.

MAP EXTENT: 1. The rectangular limits (xmin,ymin and xmax,ymax) of the area of the Earth's surface displayed using ArcInfo. Map extent is specified in the coordinate system of the coverage or other geographic data set used. Typically, the extent of the geographic database (or a portion of it defined by a zoomed-in view) defines the map extent for display. 2. The geographic extent of a geographic data set specified by the minimum bounding rectangle (i.e., xmin,ymin and xmax,ymax).

MAP LIBRARY: An organized, uniformly defined collection of spatial data partitioned by layers and tiles into component parts called map sections. A map library organizes geographic data spatially as a set of tiles and thematically as a set of layers. The data in a map library are indexed by location for optimal spatial access. A map library organizes coverages spatially by tiles and thematically by layer.

NODE: The beginning and ending locations of an arc.

OPERATING SYSTEM: Computer software designed to allow communication between the computer and the user. The operating system controls the flow of data, the application of other programs, the organization and management of files, and the display of information.

OVERSHOOT: That portion of an arc digitized past its intersection with another arc.

PIXEL: A contraction of the words picture element. The smallest unit of information in an image or raster map. Referred to as a cell in an image or grid.

POLYGON: A coverage feature class used to represent areas. A polygon is defined by the arcs that make up its boundary and a point inside its boundary for identification. Polygons have attributes (PAT) that describe the geographic feature they represent.

RASTER: A cellular data structure composed of rows and columns for storing images. Groups of cells with the same value represent features. See also grid.

RELATIONAL DATABASE: A method of structuring data as collections of tables that are logically associated to each other by shared attributes.

RESOLUTION: Resolution is the accuracy at which a given map scale can depict the location and shape of geographic features. The larger the map scale, the higher the possible resolution. As map scale decreases, resolution diminishes and feature boundaries must be smoothed, simplified, or not shown at all. For example, small areas may have to be represented as points.

SUBCLASS: A special feature class in a coverage which allows many features of the same class to be defined. Annotation, region, route-system, and section are types of subclasses. For example, a road coverage may have three route-systems stored as subclasses for mail delivery, street cleaning, and garbage pickup.

TABLE: A set of data elements that has a horizontal dimension (rows) and a vertical dimension (columns) in a relational database system. A table has a specified number of columns but can have any number of rows.

TEMPLATE: A coverage containing common feature boundaries, such as land-water boundaries, for use as a starting place in automating other coverages.

THEME: A user-defined perspective on a coverage, grid, tin or image geographic data set specified, if applicable, by a coverage name and feature class or data set name, attributes of interest, a data classification scheme, and theme-specific symbology for drawing.

TIC: Registration or geographic control points for a coverage representing known locations on the Earth's surface. Tics allow all coverage features to be recorded in a common coordinate system (e.g., Universal Transverse Mercator [UTM] meters or State Plane feet). Tics are used to register map sheets when they are mounted on a digitizer and to transform the coordinates of a coverage (e.g., from digitizer units [inches] to UTM meters).

TILE: The spatial unit by which geographic data is organized, subdivided, and stored in a map library. Tiles subdivide the area covered by a map library and organize the library data by location (e.g., counties might be the tiles in a statewide database). A tile can be a regular, geometric shape (e.g., a map sheet), or an irregular shape, such as a county boundary.

TOPOLOGY: The spatial relationships between connecting or adjacent coverage features (e.g., arcs, nodes, polygons, and points). For example, the topology of an arc includes its from- and to-nodes, and its left and right polygons. Topological relationships are built from simple elements into complex elements: points (simplest elements), arcs (sets of connected points), areas (sets of connected arcs), and routes (sets of sections, which are arcs or portions of arcs). Redundant data (coordinates) are eliminated because an arc may represent a linear feature, part of the boundary of an area feature, or both. Topology is useful in GIS because many spatial modeling operations don't require coordinates, only topological information. For example, to find an optimal path between two points requires a list of the arcs that connect to each other and the cost to traverse each arc in each direction. Coordinates are only needed for drawing the path after it is calculated.

UNDERSHOOT: An arc that does not extend far enough to intersect another arc. See also dangling arc.

UNION: A topological overlay of two polygonal spatial data sets which preserves features that fall within the spatial extent of either input data set; that is, all features from both coverages are retained.

UNIVERSAL POLYGON: The first record in a polygon attribute table. It represents the area beyond the outer boundary of the coverage. It's the only polygon that never has a label point, and so has a User-ID value of 0. Its area equals the negative sum of all the polygons in the coverage. Also referred to as the external polygon.

VECTOR: A coordinate-based data structure commonly used to represent linear geographic features. Each linear feature is represented as an ordered list of vertices. Traditional vector data structures include double-digitized polygons and arc-node models.

WAN: Wide area network. Computer data communications technology that connects computers at remote sites. WANs are composed of special data communications hardware and software and usually operate across public or dedicated telephone networks.

WEED TOLERANCE: The minimum allowable distance between any two vertices along an arc. Weed tolerance is a parameter that can be set before adding arc features. When adding new arcs, if an input vertex is within the weed distance of the last vertex, it is disregarded. When weeding existing arcs, it is the tolerance used by the Douglas-Peucker algorithm. Nodes are always retained. The proximity of vertices on one arc to vertices on another arc within the tolerance does not cause them to be weeded; this is controlled by the proximal tolerance.

Source: ESRI's Dictionary of GIS Terminology January 2001

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Healthcare: You find these Links to Healthcare Resources helpful.

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I.B.C. : International Building Code

I.C.B.O.: International Conference of Building Officials

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A.S.H.R.A.E.: American Society of Heating, Refrigeration and Air Conditioning Engineers

A.S.M.E.: American Society of Mechanical Engineers

H.V.A.C.: Heating, Ventilation & Air Conditioning

U.M.C.: Uniform Mechanical Code

A/C: Air conditioner, can be wall hung, roof mount, thru wall. Rated according to cooling capacity in BTU's or tons. Usually comes with electric resistance heat.

Baseboard Heat: Electric Resistance heating units located near base of wall. Rated according to heating capacity in kw's.

BTU: British Thermal Units. Rating for cooling or heating capacity. 12,000BTU's is equal to 1 ton.

Damper: a blade or blades installed in a duct to open or close for the adjustment of air flow.

Diffuser: The round or square device at end of ductwork which enters a room and diffuses or disperses the heat or air conditioning.

Duct: Round or rectangular metal pipe for distributing warm or cooled air from air conditioner. Usually located in ceiling space.

Heat Pump: Type of air conditioner that can economically provide warm air as well as cooled air.

H.V.A.C.: Heating, Ventilation & Air Conditioning

KW: Kilowatt – equals 1,000 watts, unit of measure of electrical power.

Plenum: A chamber or space forming a part of an air conditioning system. Plenum wall on a trailer refers to the interior partition just inside the end wall where the air conditioner is located. The air space provide by the gap between the two walls is used to allow return air to get to the air conditioner. Allows return air to be ducted out of each individual room in the trailer, rather than returning air thru grilles in each room door. More expensive than return air direct at unit grille.

Resistance Heat: Term for the heat developed by running electricity thru a coil of wires similar to a toaster. Straight air conditioners (non-heat pumps) usually provide heat this way. Air conditioner with resistance heat is less expensive to purchase than heat pumps, but more expensive to operate than heat pump.

Return Air: Refers to the air that is drawn back out of a room or area to go back through air conditioner to be reheated or cooled. Can be returned through return grill at air conditioner unit, or return duct.

Supply Air: Refers to the air that is blown into a room or area out of the air conditioner unit. Can be supplied directly from air conditioner, or thru supply duct.

T-Stat: Thermostat. Device used to control temperature in a space. Types of T-stats include manual switchover (must tell air conditioner to put out heat or cold), or automatic switchover.

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ABS: Type of waste piping.

China: Vitreous china. Ceramic type finish for plumbing fixtures such as lavatories and water closets.

Copper: Type of piping usually used for supply water. Standard pipe is type “L"copper. Copper type refers to wall thickness of pipe. Type “K”, “L”, or “M”, with “M"being the thickest.

DWV: (Drain, Waste, Vent) Drain piping usually ABS or PVC Schedule 40.

I.A.P.M.O.: International Association of Plumbing and Mechanical Officials

Lavatory: Term for a sink in a rest room.

Manifold: Term to mean the joining together of all the plumbing fixture waste pipe drops.

PVC: Poly-vinyl chloride. Type of plastic piping. Usually used for waste piping, occasionally used for supply piping.

Schedule: Term for wall thickness of piping. The higher the number, the thicker the pipe.

Supply: Piping for fresh water, usually type “L"copper.

SS: Stainless Steel.

U.P.C.: Uniform Plumbing Code

Water Closet: Term for a flushable toilet.

Water Cooler: Term for a refrigerated drinking fountain.

PA L&I: Pennsylvania Labor & Industry. Similar to a state approval. Cannot be done by third party. Must be approved by PA L&I.

ACCESSORY USE: The use of a building, structure or land that is subordinate to, customarily incidental to, and ordinarily found in association with, a principal use, which it serves. ACRE: 43,560 square feet (about the size of a football field).

ACTIVITY CENTER: A community focal point providing for the combination, rather than scatteration, of general retail, service commercial, professional office, higher density housing, and appropriate public/quasi-public uses. (See VILLAGE ACTIVITY CENTER, COMMUNITY ACTIVITY CENTER, AND MAJOR COMMUNITY ACTIVITY CENTER.)

ADEQUATE PUBLIC FACILITIES (APF) ORDINANCE: The ordinance requiring a determination of the adequacy of public facilities to accommodate growth resulting from approval of a subdivision application.

AFFORESTATION: The establishment of a tree cover on an area from which it has always or very long been absent, or the planting of open areas that are not presently in forest cover. (See also REFORESTATION)

AGRICULTURAL ASSESSMENT: A state program in which land used for agricultural purposes is assessed based on its value as agricultural land as opposed to a higher valuation.

AIR INSTALLATION COMPATIBLE USE ZONE (AICUZ) STUDY: An extensive analysis of the effects of noise, aircraft accident potential, and land use and development upon present and future neighbors of Andrews Air Force Base.

AIR RIGHTS: The development rights of the space above a piece of land and its existing ground level use.

ANCILLARY: Certain small shops, stores, restaurants associated with larger uses, e.g., office and residential, that supply necessities in frequent demand and the daily needs of an area, with a minimum of consumer travel (e.g., restaurants, dry cleaners in an office or mid-rise residential building).

AREA MASTER PLAN OR AREA PLAN: Area Master Plans: Area master plans consist of a plan map along with supporting data, text and other maps. They provide specific recommendations on a planning area or subregion basis on the environment, historic preservation, living areas, housing, commercial areas, employment areas, urban design, circulation, and transportation.(See also MASTER PLAN.)

ARTERIAL: A highway, usually within a 120-foot right-of-way, for through traffic with access controlled to minimize direct connections, usually divided and on a continuous route.

AT-GRADE: Level for a road, building or other structure at the same grade or level as the adjoining property (as opposed to a depressed or elevated road, building or other facility).

AVERAGE DAILY TRAFFIC (ADT): The average number of vehicles passing a specified point on a highway during a 24-hour period.

BASIC PLAN: Phase 1 of the Comprehensive Design Zone process. It sets forth general land use relationships, including the approximate number of dwelling units and building intensity. Proposed land uses are also described. (See COMPREHENSIVE DESIGN ZONE.) (See also COMPREHENSIVE DESIGN PLAN AND SPECIFIC DESIGN PLAN.)

BERM: An earthen mound designed to provide visual interest on a site, screening of undesirable views, noise reduction, etc.

BEST MANAGEMENT PRACTICES (BMPs): Conservation practices or systems of practices and management measures that control soil loss and reduce water quality degradation caused by nutrients, animal waste, toxins and sediment.

BIKEWAY: A lane, path or other surface reserved exclusively for bikers.

BUFFER: An area of land designed or managed for the purpose of separating and insulating two or more land areas whose uses conflict or are incompatible (trees separating homes from an expressway).

BUFFERYARD: One of several specific combinations of minimum building setbacks, landscaped yard widths, and plant material requirements set forth in the Landscape Manual for use in buffering incompatible land uses.

BUILD-OUT: A theoretical measure of "full development" for which public facilities are planned. (See HOLDING CAPACITY.)

BUS RAPID TRANSIT (BRT): A fixed guideway transit (FGT) system in which transit buses operate on rights-of-way that are physically or otherwise off-limits to regular vehicular traffic. These systems are often constructed so that they can be upgraded to light-rail vehicle operations when ridership grows beyond the operational capacity of transit buses. The state Department of Transportation is considering bus rapid transit for several major arterial roads in Prince George's County.

CAPACITY: The maximum number of vehicles that have a reasonable expectation of passing over a given section of a lane or a roadway during a given period under a specified speed or level of service. Strictly, capacity is an absolute number equivalent to Level-of-Service E. (See LEVEL OF SERVICE.)

CAPITAL IMPROVEMENT PROGRAM (CIP): A six-year comprehensive statement of the objectives of capital programs with cost estimates and proposed construction schedules for specific projects. The CIP is submitted annually to the County Council by the County Executive.

CHARRETTE: A brief, intense design workshop in which community teams work together with municipal staff, city council members, the landowner, the developer, and all interested citizens in order to produce a plan that addresses the needs of the community.

CHESAPEAKE BAY CRITICAL AREA: All waters of and lands under the Chesapeake Bay and its tributaries to the head of tide as indicated on the state wetlands maps, and all land and water areas within 1,000 feet beyond the landward boundaries of and heads of tides as indicated on approved Chesapeake Bay Critical Area Overlay Zoning Map Amendments.

CLUSTER DEVELOPMENT: An alternative development technique under zoning and subdivision regulations. A cluster subdivision is basically one in which a number of residential lots are grouped or clustered, leaving some land undivided for common use. Generally the same number of lots or dwelling units permitted under conventional subdivision procedures are clustered on smaller-than-usual lots. The land remaining from lot reduction is left undivided and is available as common area or open space.

COLLECTOR: A two- to four-lane roadway, usually within an 80-foot right-of-way, providing movement between developed areas and the arterial system with minimum control of access.

COMMISSION 2000: A 53-member broad-based, blue ribbon panel appointed by the County Executive and the County Council charged with the preparation of a Biennial Growth Policy Plan. The plan was adopted, with amendments, as the Interim General Plan in November 2000.

COMMUNITY ACTIVITY CENTER (as defined in Master Plans): A commercial center containing 10-25 acres of commercial development on a site area of 20-30 acres, serving a population of at least 50,000 and anchored by a general merchandise store and may also include a supermarket. A community activity center should also include other commercial, public/quasi-public and residential uses. (See also ACTIVITY CENTER.)

COMMUNITY CENTERS: Concentration of activities, services and land uses that serve, and are focal points for, the immediate neighborhoods. (See also METROPOLITAN AND REGIONAL CENTERS.)

COMMUNITY (as defined in some master plans): A grouping of neighborhoods and villages, the population of which may range from 23,000 to 30,000 in suburban areas and up to 40,000 in corridor communities. Most communities should have as their centers of focal points a Community Activity Center. (See NEIGHBORHOOD and VILLAGE.)

COMPREHENSIVE DESIGN PLAN (CDP): Phase II of the Comprehensive Design Zone process. It establishes the general location, distribution, and size of proposed structures. (See COMPREHENSIVE DESIGN ZONE.) (See also BASIC PLAN AND SPECIFIC DESIGN PLAN.)

COMPREHENSIVE DESIGN ZONE (CDZ): Provisions enacted in the Zoning Ordinance and Subdivision Regulations providing developers the opportunities to comprehensively plan all aspects of a development, from zoning and land use to the final specific details of the site, architecture, and landscaping. The process involves a three-phase (Basic Plan, Comprehensive Design Plan, and Specific Design Plan) site plan review procedure, which may result in specific density or intensity increments being added to a base density or intensity in return for the provision of certain public benefits.

COMPREHENSIVE MASTER PLAN: (See MASTER PLAN.)

COMPREHENSIVE REZONING: (See SECTIONAL MAP AMENDMENT [SMA].)

COMPREHENSIVE TEN-YEAR WATER AND SEWERAGE PLAN: A plan required by the state and adopted annually by the county that describes county policy related to water and sewerage planning and delineates geographic areas to be serviced over the next ten years.

CONSERVATION AGREEMENT: A formal agreement that commits a grading or building permit applicant within the Chesapeake Bay Critical Area to the execution of various approved elements of a Conservation Plan, including a stormwater management concept plan, an erosion and sedimentation concept plan, a vegetation management plan, and other plans that may be required by the Department of Environmental Resources or the Prince George's County Planning Board.

CONSERVATION EASEMENT: A nonpossessory interest in land that restricts the manner in which the land may be developed in an effort to preserve natural resources for future use.

CONSERVATION MANUAL: The manual that describes how a Conservation Plan is to be prepared in order to meet the requirements of the Chesapeake Bay Critical Area program, and which is adopted by the District Council and revised and amended from time to time by the District Council.

CONSOLIDATED TRANSPORTATION PROGRAM (CTP): The state transportation capital improvement plan, including all state-funded or sponsored road, transit, bike/pedestrian projects, and studies to be undertaken in Prince George's County.

CONSTRAINED LONG-RANGE PLAN (CLRP): The approved regional plan for highway, transit, and bikeway projects, as well as major jurisdictional and regional studies. Individual jurisdictional submissions are prepared by the District of Columbia, Maryland and Virginia for the National Capital Transportation Planning Board. To be eligible for federal financial assistance, a Prince George's County highway, transit, trail or bikeway project, or major transportation study, such as those proposed or required by the new General Plan or the Master Plan of Transportation (see below), will have to be submitted to the state for inclusion in the Maryland section of the CLRP and the appropriate Transportation Improvement Plan (TIP) (see below).

CONTROLLED INTERSECTIONS: Intersections with traffic lights or other traffic control devices.

COOPERATIVE FORECASTS: A series of population, household, and employment forecasts prepared by local jurisdictions through the auspices of the Metropolitan-Washington Council of Governments (COG).

CORRIDOR(S): a. An uninterrupted path or channel of developed or undeveloped land paralleling the route of a street or highway. b. The land within one-quarter mile of both sides of designated high-volume transportation facilities, such as arterial roads. If the designated transportation facility is a limited access highway, the corridor extends one-quarter mile from the interchanges.

DECIBEL“A"WEIGHTED (dBA): A measure of sound levels in average decibels usually over a 24-hour period calculated using a logarithmic average.

DENSITY: The number of dwelling units or persons per acre of land, usually expressed in units per gross acre. Single-family detached dwellings (range from less than 1 to 6 per acre) on a single lot. Townhouses (range from 6 to 12 per acre) attached in a row. Multifamily Apartments (range from 12 to 48 per acre) in one structure.

DEVELOPED TIER (As defined by the 2002 General Plan): The subarea of the county consisting primarily of inner-county areas that are largely developed. (See DEVELOPING TIER and RURAL TIER.)

DEVELOPING TIER (As defined by the 2002 General Plan): The largely suburban subarea of the county located primarily in the central portion of the county. (See DEVELOPING TIER and RURAL TIER.)

DEVELOPMENT (as defined in Zoning Ordinance): Any activity that materially affects the condition or use of dry land, land under water, or any structure.

DOWNZONING: A popular term for an action that changes a property to a lower density, in effect limiting development to less-intense uses than previously permitted.

DWELLING UNIT: A room or group of rooms, occupied or intended for occupancy as separate living quarters.

EASEMENT: A contractual agreement to gain temporary or permanent use of, and/or access through, a property, usually for public facilities and access ways.

ECOLOGICAL FUNCTION: The functions of a natural system that includes water, air, soil, flora, fauna, and all related elements. These functions regulate air, water, and soil temperatures and provide appropriate habitat for ecosystem residents and migrants.

ENVIRONMENTAL IMPACT REPORT (EIR): A report prepared by M-NCPPC in accordance with Article 28, Section 8-110 for all requests for special exception to the zoning regulations for the mining of sand and gravel.

ENVIRONMENTAL IMPACT STATEMENT (EIS): A document, prepared by a federal agency, on the environmental impact of its proposals for legislation and other major actions that significantly affect the quality of the human environment. Environmental Impact Statements are used as tools for decision making and are required by the National Environmental Policy Act. Similar environmental analyses are undertaken by state and local agencies.

ENVIRONMENTAL SETTING: Used in the Historic Sites and Districts Plan to define an area of land (including or within the property boundaries) to which a historic resource relates visually and historically, and which is essential to the integrity of the historic resource.

EUCLIDEAN ZONE: A traditional zone in which certain types of land uses with specific regulations are permitted. Euclidean zones can be granted by the District Council upon approval of a comprehensive rezoning or a piecemeal rezoning application. Through a piecemeal application the property owner must demonstrate either that a change in the character of the neighborhood has occurred since the last comprehensive rezoning; or 2) that a mistake was made in the last comprehensive rezoning.

EXPRESSWAY: A divided highway, generally within a 150-200 foot right-of-way, with full or partial control of access and interchanges at selected public roads, with some at-grade intersections spaced at 1,500 foot to 2,000 foot intervals.

FAR: (See FLOOR AREA RATIO)

FINAL PLAT: The final detailed drawing (to scale) of a tract of land, depicting the proposed division of the tract into lots, blocks, streets, alleys, or other areas within a proposed subdivision. (See Subtitle 24 for further information regarding Subdivisions.)

Fixed Guideway Transit (FGT): Transit service provided on its own right-of-way: a rail track, physically restricted vehicle lanes, or a dedicated roadway in the road and highway system. Both the Metrorail regional rapid transit and MARC commuter rail systems that serve Prince George's County are FGT systems.

FLAG LOT: A flag-shaped lot, created under the Optional Residential Design Approach provisions of Subtitle 24, which has a street frontage smaller than that other required for the zone in which it is located.

FLOATING ZONE: A zone that is more flexible than euclidean zones in terms of permissible densities, intensities and land uses and overall development design opportunities. Most floating zones require the following findings by the District Council to be granted: 1) The proposed zone is in conformance with the Master Plan; 2) Is compatible with the surrounding community; and 3) Meets the purposes of the zone. Findings of change or mistake, required for granting a euclidean zone, are not required for floating zones. Some floating zones require Master Plan recommendation.

FLOODPLAIN: A relatively flat or lowland area adjoining a river, stream, or watercourse, which is subject to periodic, partial or complete inundation.

FLOOR AREA RATIO (FAR): The ratio of the gross floor area of a building to the area of the lot on which it is located.

FORECAST: As defined for use in the Council of Governments (COG) Cooperative Forecasting Program, a projection tempered by stated policy considerations, including the reconciliation of past and current trends with current and future policies. Ideally, forecasts reflect the best professional judgment concerning the impact of trends and present conditions on the future trend of development and the likely effectiveness of policies to alter this trend. Therefore, forecasts should represent the most realistic assessment of the future.

FOREST STAND DELINEATION: A detailed accounting of woody vegetation, prepared in document form, as required by the Prince George's County Woodland Conservation and Tree Preservation Policy Document.

FREEWAY: A divided highway for through traffic with full control of access and interchanges at selected public roads only.

FUNCTIONAL PLAN: A plan for a specific, generally Countywide concern, such as highways, schools, hospitals, or fire stations.

FUNCTIONAL PLANS: Map and supporting text that comprehensively cover a specific topic (such as public safety, transportation or historic preservation) for the entire county.

GENERAL PLAN: The Prince George's County General Plan, approved by the County Council in October 2002, provides long-range guidance for the future growth of the county. It identifies Centers and Corridors where intensive mixed use (residential, commercial and employment development) is to be encouraged. The plan also divides the county into three development tiers (Developed, Developing, Rural) recognizing the different development goals and needs of different parts of the county. The plan also makes recommendations for infrastructure elements: green infrastructure, transportation systems, and public facilities. The plan includes guidance for economic development, revitalization, housing, urban design and historic preservation. Future implementation efforts are outlined.

GEOGRAPHIC INFORMATION SYSTEM (GIS): An organized collection of computer hardware, software and geographic data designed to efficiently capture, store, update, manipulate, analyze and display all forms of geographically referenced information.

GREEN AREA: An area of land associated with, and located on the same parcel of land as, a building for which it serves to provide light and air, or scenic, recreational, or similar purposes.

GREEN BUILDING: Practices that consider the impacts of buildings on the local, regional, and global environment, energy and water efficiency, reduction of operation and maintenance costs, minimization of construction waste, and eliminating the use of harmful building materials.

GREEN CORRIDOR: See GREEN INFRASTRUCTURE

GREEN HUB: See GREEN INFRASTRUCTURE

GREEN INFRASTRUCTURE: A network of large undisturbed land areas (hubs) connected by designated pathways for the movement of wildlife and humans (green corridors).

GREENWAYS: Areas of protected open space that follow natural and manmade linear features for recreation, transportation and conservation purposes and link ecological, cultural and recreational amenities.

GROSS FLOOR AREA (GFA): The total number of square feet of floor area in a building.

HIGH-OCCUPANCY VEHICLE (HOV): A passenger vehicle containing more than one person. HOV facilities—such as John Hanson Highway (US 50) in Prince George's County—generally require a minimum number of occupants for a vehicle to be granted access to HOV lanes.

HISTORIC DISTRICT: A group of historic resources comprised of two or more properties that are significant as a cohesive unit and contribute to the historical, architectural, archeological, or cultural values within the Maryland-Washington Regional District and that has been so classified in the county's Historic Sites and Districts Plan.

HISTORIC RESOURCE: An area of land, building, structure or object that may be significant in American history, architecture, archaeology, or culture. Historic resources, designated as such in the county's Historic Sites and Districts Plan are considered unclassified and are not protected by the Prince George's County Historic Preservation Ordinance.

HISTORIC SITE: An individual historic resource that is significant in American history, architecture, archaeology, or culture and is so designated on the county's Historic Sites and Districts Plan. A historic site is protected by the Prince George's County Historic Preservation Ordinance.

HOLDING CAPACITY: The estimate of the maximum housing and employment development permitted by an area's zoning.

IMPERVIOUS SURFACE: In environmental language, a surface, such as pavement or a building, that water cannot penetrate or permeate.

INFILL DEVELOPMENT: Development that takes place on vacant or underutilized parcels within an area that is already characterized by urban development and has access to urban services.

INFRASTRUCTURE: The built facilities, generally publicly funded, that are required in order to serve a community's developmental and operational needs. The infrastructure includes such things as roads and water and sewer systems.

INTENSITY: A term referring to the gross (total) floor area and/or the degree to which commercial and industrial land uses generate traffic, noise, air pollution and other potential problems, for commercial and industrial uses.

INTERMODAL SURFACE TRANSPORTATION EFFICIENCY ACT (ISTEA): An act to develop a national intermodal transportation system that is economically efficient, environmentally sound, provides a foundation for the nation to compete in the global economy, and will move people and goods in an energy-efficient manner.

LAND USE (OR USE): The types of buildings and activities existing in an area or on a specific site. Land use is to be distinguished from zoning, the latter being the regulation of existing and future land uses.

LANDSCAPE MANUAL: Part of the County Zoning Ordinance, its purpose is to enhance the appearance of the County by improving the quality of landscaping, buffering and screening. The manual establishes minimum mandatory standards and provides options that will allow approval of alternative methods of compliance.

LEVEL OF SERVICE (LOS): a. A set of operating conditions describing the ability of a road network to handle traffic. Level A specifies the best traffic conditions; Level F indicates gridlock. b. The adequacy of the road and street network in the county transportation system is generally measured and expressed in terms of its LOS. Each level of service is one in a hierarchy of indices that evaluate the level and severity of automotive traffic congestion on a specific road segment or at specific intersections. The General Plan recommends the minimum acceptable LOS by Tier.

LIGHT RAIL: Urban rail vehicles operating predominantly on private rights-of-way at surface level or fully grade separated, e.g., Metro.

LIGHT SPILL-OVER: Light from nonnatural sources that covers areas beyond that needed for the lighting use or that trespasses onto another person's property.

LOT COVERAGE: The percentage of a lot that is covered by buildings (including covered porches) and areas for vehicular access and parking of vehicles. MAJOR COMMUNITY ACTIVITY CENTER (as defined in master plans): A commercial center containing 20-50 acres of commercial development on a site area of 30-60 acres, serving a population of at least 150,000. A major community activity center typically includes uses listed under community activity center plus one or more general merchandise anchor stores. Can also be defined as a community focal point providing for a concentration of activities such as general retail, service commercial, professional office, higher-density housing, and appropriate public and open space uses easily accessible by pedestrians. (See also ACTIVITY CENTER.)

MANDATORY (LAND) DEDICATION: Land excluded from subdivision approved for residential development. The land is dedicated to M-NCPPC (or held in private ownership) for the purpose of providing suitable and adequate open space, light, and air to serve the recreational needs of the future occupants of the subdivision.

MASTER PLAN: A document that guides the way an area should be developed. It includes a compilation of policy statements, goals, standards, maps and pertinent data relative to the past, present, and future trends of a particular area of the County including, but not limited to, its population, housing, economics, social patterns, land use, water resources and their use, transportation facilities, and public facilities. In Prince George's County, master plans amend the county's General Plan.

MASTER PLAN OF TRANSPORTATION (MPOT): A countywide functional, comprehensive plan of street, road, and highway; transit; and trail, bike and pedestrian facilities needed to ensure the operational integrity of the county transportation system and to complement the development and growth envisioned and recommended in the General Plan, and adopted and approved area plans, in Prince George's County.

METROPOLITAN CENTERS: Areas of the county with a high concentration of land uses (such as government service or major employment, major educational complexes, high-intensity commercial uses) that attract employers and customers from other parts of the metropolitan Washington region. Metropolitan centers are, or may be, cost-effectively served by mass transt. (See also COMMUNITY AND REGIONAL CENTERS.)

MIXED-USE ZONING: Zoning that permits a combination of uses within a single development. Many zoning districts specify permitted combinations of, for example, residential and office/commercial uses. The term has also been applied to major developments, often with several high-rise buildings, that may contain offices, shops, hotels, apartments and related uses.

MODERATELY PRICED DWELLING UNIT (MPDU): A dwelling unit that is constructed, sold, or rented pursuant to Subtitle 13, Division 8 of the Prince George's County Code.

NATURAL RESERVE AREA: A delineation (usually on master plans) of physical features that exhibit natural constraints that make conditions unsuitable for development or that are important to sensitive ecological systems. The physical features that delineate the Natural Reserve Area are: the streams and their buffers, including the 100-year floodplain and nontidal wetlands. Also included are severe slopes and steep slopes associated with highly erodible soils, the Patuxent River Primary Management Area, Chesapeake Bay Critical Area buffers, and Marlboro clay on steep slopes.

NEIGHBORHOOD: (As defined in some master plans) The smallest unit of community structure. Neighborhood population ranges from 3,000 to 6,000, depending on the ratio of single-family to multifamily housing. (See VILLAGE and COMMUNITY).

NEIGHBORHOOD CONVENIENCE CENTER(as defined in master plans): A commercial center containing 2-6 acres of commercial development on a site of 4-10 acres, serving a population of approximately 8,000 and anchored by a small grocery or drug store. It should also include a limited range of other commercial and residential uses.

NET LOT AREA: The total contiguous area included within a lot, excluding public ways (i.e., streets, alleys) and land with 100-year floodplain. (See Section 27-107.01 of the Zoning Ordinance.)

NODE: A location along a corridor at a major intersection or major transit stop (bus or rail) that consists of a concentration of high-intensity, mixed-use residential and commercial development. Nodes should be interspersed with stretches of lower intensity land uses or open space.

NONATTAINMENT AREA: A geographic area in which the level of a criteria air pollutant is higher than the level allowed by federal standards. Portions of Prince George's County are currently classified as nonattainment for carbon monoxide and all of the county is a nonattainment area for ozone.

NONCONFORMING BUILDING OR STRUCTURE: Any building or structure that is not in conformance with a requirement of the zone in which it is located (as it applies to the building or structure), provided that: (a) The requirement was adopted after the building or structure was lawfully erected; or (b) The building or structure was erected after the requirement was adopted and the District Council has validated a building, use and occupancy, or sign permit issued for it in error.

NONCONFORMING USE: A use that is prohibited by, or does not conform to, the Zoning Ordinance. Except when construction has occurred in outright violation of the code, nonconforming uses are generally ones that were allowed under the original zoning but have not been allowed since the land was rezoned or the law changed. The use may continue to operate subject to limitations.

NONTIDAL WETLAND: An area inundated or saturated by surface or groundwater at a frequency and duration sufficient to support a prevalence of vegetation typically adapted for life in saturated soil conditions under normal circumstances. Nontidal wetlands are also referred to as swamps, marshes and bogs. OPEN SPACE (land use, not zoning): Areas of land not covered by structures, driveways, or parking lots. Open space may include homeowners association common areas, parks, lakes, streams and ponds, etc.

OPPORTUNITY HOUSING: Dwellings constructed by a not-for-profit housing organization pursuant to Subtitle 13, Division 8, of the Prince George's County Code. PATTERN OF DEVELOPMENT: The physical form or shape of land development.

PATUXENT RIVER PRIMARY MANAGEMENT AREA (PMA): An area along all perennial streams in the Patuxent River watershed within which land use is managed to protect water quality and preserve wildlife habitat.

PEDESTRIAN-ORIENTED DESIGN: Land use activities that are designed and arranged in a way that emphasizes travel on foot rather than by car. The factors that encourage people to walk are often subtle, but they most regularly focus upon the creation of a pleasant environment for the pedestrian. Elements include compact, mixed-use development patterns with facilities and design that enhance the environment for pedestrians in terms of safety, walking distances, comfort, and the visual appeal of the surroundings. Pedestrian-friendly environments can be created by locating buildings close to the sidewalk, by lining the street with trees, and by buffering the sidewalk with planting strips or parked cars, small shops, street-level lighting and signs, and public art or displays.

PERSON OF RECORD (PARTY OF RECORD): (A) In any zoning case, a Person of Record shall include: 1. The owner, applicant and correspondent. 2. Any municipality or person who (in writing) requests to become a Person of Record during testimony before the Zoning Hearing Examiner (ZHE) or prior to the case having been taken under advisement by the ZHE. 3. The Development Review District Commission if the property is located in a Development Review District. (B) In any sectional map amendment (SMA) or other matter (under the Zoning Ordinance) not heard by the ZHE, Person of Record shall include the owner, applicant and correspondent of a pending Zoning Map Amendment or other pertinent application; person or municipality who, in writing or in testimony before the District Council, Planning Board, or other applicable hearing body, requests to be made a Person of Record, and the Development Review District Commission if the property is located in a Development Review District, prior to the closing of the hearing record on the matter.

PIECEMEAL REZONING: The rezoning of individual properties, one-by-one, upon the petitioning of individual property owners. Piecemeal rezoning can include euclidean zones, floating zones and comprehensive design zones.

PIPELINE DEVELOPMENT: A colloquial term encompassing projects that have received development approval and public commitments are in effect, but development has not yet been completed. For example, the number of housing units "in the pipeline" would be accounted for in the construction permits, sewer connection authorizations, or subdivision approval for housing.

PLANNING AREA: A district geographically defined by natural or manmade boundaries as described in the Zoning Ordinance. It is the smallest geographical area for which a master plan is prepared. Prince George's ounty is divided into 37 planning areas, covering all of the county with the exception of the City of Laurel (which is not under M-NCPPC jurisdiction).

POLLUTION: The presence of matter or energy, the nature, location, or quantity of which produces undesirable environmental effects. (a.) Nonpoint source pollution—Pollution generated by diffuse land use activities rather than from an identifiable or discrete facility. It is conveyed to waterways through natural processes, such as rainfall, stormwater runoff, or groundwater seepage rather than by deliberate discharge. (b.) Point source pollution—In air pollution, a stationary source of large individual emission, generally of an industrial nature. In water pollution, a stationary source of wastewater discharge into a stream, such as from a factory or sewage treatment plant.

PRELIMINARY PLAN OF SUBDIVISION: The preliminary detailed drawing (to scale) of a tract of land, depicting its proposed division into lots, blocks, streets, alleys, or other designated areas within a proposed subdivision.

PUBLIC FACILITY: A facility such as a road, school or sewage treatment plant financed by public revenues and available for use by the public.

PUBLIC IMPROVEMENTS: A variety of facilities and services provided by government such as street lighting, street widening, trash collection, and drainage systems. RECLAMATION: The action of returning to use, such as the returning of strip-mined land to a new use by recontouring and replanting.

RECORD PLAT: An official plat of subdivision as recorded in the Land Records of Prince George's County, Maryland.

RECREATION—ACTIVE: Includes activities such as swimming, skating, hiking, biking, fitness trails, frisbee or conventional golf, baseball, basketball, etc.

RECREATION—PASSIVE: Reading, sitting on a park bench, viewing scenery, picnicking and/or visiting with friends.

REFORESTATION: The replanting of trees on recently forested land as required by the publication, A Technical Manual for Woodland Conservation with Development in Prince George's County (October 1992). (See also AFFORESTATION.)

REGIONAL CENTERS: Concentrations of regionally marketed commercial and retail centers, office and employment areas, some higher-education facilities, and possibly sports and recreational complexes. Regional centers are, or can be, effectively served by mass transit. (See also COMMUNITY AND METROPOLITAN CENTERS.)

REGIONAL DISTRICT ACT: An act of the Maryland State Legislature that sets forth the duties and responsibilities for planning, zoning and subdivision in Prince George's County (except the City of Laurel). The act (Article 28) delegates these responsibilities to the District Council and the Maryland-National Capital Park and Planning Commission.

REMAND DE NOVO: A return of a zoning case back to the Planning Board for the purpose of processing the application over again as if it were a new one.

REVITALIZATION OVERLAY: A method of designating areas that will be targeted for revitalization assistance. Designations will be temporary (generally from five to ten years), limited in size (generally no larger than ten acres) and will focus attention on neighborhoods that are experiencing: (1) problems with attracting investment due to obsolescent infrastructure and facilities, and/or (2) concentrated levels of household poverty with elevated levels of social and economic distress.

RIGHT-OF-WAY: (A.) A general term denoting land or an interest therein, usually in a strip, devoted to transportation or other public purposes (e.g., utilities). (B.) the legal right to pass through the grounds of another; also the public strip of land on which a highway, railroad, transit line or other public utility (power and sewer lines) are built.

RUBBLEFILL: Fill placed in a controlled manner consisting of construction and/or building demolition rubble, including both irreducible materials (concrete, rock, brick) and those subject to decay (lumber). Such fills, in addition to rubble, may accept root material, brush, tree limbs, and stumps.

SANITARY LANDFILL: A planned and systematic method of refuse disposal whereby the waste material is placed in the earth in layers, then compacted and covered with earth or other approved material.

SCREENING: A method of reducing the impact of visual and/or noise intrusions through the use of plant materials, berms, fences and/or walls, or any combination thereof. Screening blocks that which is unsightly or offensive with a more harmonious element.

SECTIONAL MAP AMENDMENT (SMA): (A) The rezoning of a planning area (or a combination of planning areas, municipalities, those areas subject to a master plan, or areas subject to an adopted urban renewal plan), either selectively or in its entirety, to implement a master plan and policies to achieve specified planning goals. (B) A legislative act that implements the land use recommendations contained in a master plan by comprehensively rezoning property to reflect master plan policies, but need not follow all master plan land use policies or recommendations.

SENSITIVE ENVIRONMENTAL FEATURES: These features include streams, stream valleys, and their associated features; the habitats of state-listed species that are rare, threatened, and endangered; 100-year floodplains; and certain high-priority forests.

SETBACK: The distance between a building or structure (not including ground-level parking lots or other paved surfaces) from property lines or from other buildings.

SEVERE SLOPES: Those slopes that are greater than 25 percent. (Example: a 25-foot change in elevation in a 100-foot horizontal distance.)

SINGLE-OCCUPANCY VEHICLE (SOV): Vehicle containing only the driver.

SKY GLOW: Light from nonnatural sources that reflects off the night sky and causes a reduction in the overall darkness of an area.

SPECIFIC DESIGN PLAN (SDP): Phase III of the Comprehensive Design Zone process. It is a precise site plan that includes exact locations of lots, buildings and streets, etc., architectural plans, exterior building elevations and detailed landscaping plans. (See COMPREHENSIVE DESIGN ZONE.) (See also BASIC PLAN AND COMPREHENSIVE DESIGN PLAN)

STAGED DEVELOPMENT: A timing concept for the staging of private development and growth in an area so that development and growth are coordinated with the provision of needed public facilities, all in accordance with an adopted policy or plan.

STATE IMPLEMENTATION PLAN (SIP): A detailed description of the programs a state will use to carry out its responsibilities under the Clean Air Act.

STEEP SLOPES: Those slopes that are between 15 and 25 percent. (Example: a 15-foot change in elevation in a 100-foot horizontal distance.)

STORMWATER MANAGEMENT: The collection, conveyance, storage, treatment and disposal of stormwater runoff in a manner to prevent accelerated channel erosion, increased flood damage, and/or degradation of water quality.

STREAM VALLEYS: Floodplains and adjacent slope areas directly associated with a stream, e.g., the Anacostia River stream valley.

STREET LINE: A line separating the street from abutting property.

STREET: A public or dedicated right-of-way at least 30 feet in width or a private road, right-of-way, or easement along which development is authorized pursuant to Subtitle 24. (See Section 27-107.01 of the Zoning Ordinance.)

STREETSCAPE: The environment of the public right-of-way as defined by adjacent private and public buildings, character of the pavement and street furniture, and use of the right-of-way.

STRUCTURE: Anything constructed or built, including parking lots and fencing. (See Section 27-107.01 of the Zoning Ordinance.

SUBDIVISION: The division by plat or deed of a piece of property into two or more lots, plots, sites, tracts, parcels, or other land divisions in accordance with Subtitle 24 of the Prince George's County Code.

SUBDIVISION REGULATIONS: Laws or regulations for the division of any land, lot or parcel into two or more lots, including the provision of streets and other public facilities.

SUBREGION: A grouping of planning areas into a larger portion of a regional area. Prince George's County is divided into seven subregions. TRADE-OFF: A balancing or exchange of factors or conditions, not all of which are attainable. Trade-offs are used in decision-making situations when complete satisfaction is not possible. Trade-offs involve sacrifice of one good for attainment of another.

TRAFFIC LEVELS OF SERVICE (LOS): See LEVELS OF SERVICE

TRANSFER OF DEVELOPMENT RIGHTS (TDR): A growth management tool used to protect designated rural and environmentally sensitive areas by allowing development rights to be transferred to properties in other parts of the county.

TRANSIT DISTRICT OVERLAY ZONE (TDOZ): A mapped zone superimposed over other zones in a designated area around a Metro station. The TDOZ may modify certain requirements for development within those underlying zones. Permitted uses of the underlying zones are unaffected. However, underlying zones can be changed via the TDOZ.

TRANSIT MASTER PLAN (TMP): A five-year comprehensive blueprint for regional and local bus and paratransit service to be provided in and by Prince George's County, prepared by the Department of Public Works and Transportation.

TRANSIT-ORIENTED DEVELOPMENT (TOD): Land uses that are sited, designed and combined to maximize transit, particularly rail, ridership.

TRANSIT SUPPORTING DEVELOPMENT (TSD): Similar to TOD, transit-supporting development is land use that is generally sited and designed to increase, as opposed to maximize, transit ridership.

TRANSPORTATION DEMAND MANAGEMENT (TDM)/TRANSPORTATION SYSTEM MANAGEMENT (TSM): Techniques used to increase the efficiency of the existing transportation system through lower cost programs like ride sharing, bus fare subsidy, parking management, and flextime.

TRANSPORTATION IMPROVEMENT PROGRAM (TIP): A six-year regional schedule for the study, acquisition, upgrading, or development of major highway, transit, bike and pedestrian facilities, and services. A joint effort of the National Capital Transportation Planning Board and its constituent jurisdictions—principally the state transportation agencies of Maryland, the District of Columbia, and Virginia—the TIP complements the CLRP (see above). Any project that is to be a candidate for federal financial assistance must be included in both plans.

TREE CONSERVATION PLAN: A site map that delineates tree save areas and text that details the requirements, penalties or mitigation negotiated during the development and/or permit review process.

URBAN DESIGN: the process of giving form, shape and character to the arrangement of buildings, to whole neighborhoods, or the city. Urban design blends architecture, landscaping and city planning concepts together to make an urban area accessible, attractive and functional.

VILLAGE ACTIVITY CENTER: (As defined in master plans) A commercial center containing 4 to 15 acres of commercial development on a site area of 10 to 20 acres, serving a population of approximately 15,000 and anchored by a supermarket. A village activity center should also include a range of other commercial uses, public/quasi-public uses, and may include residential uses. (See ACTIVITY CENTER.)

VILLAGE: (As defined in some master plans) Consists of several neighborhoods and may vary from 10,000 to 15,000 people where single-family units predominate and up to 20,000 people in corridor communities. The focal point is a Village Activity Center. (See NEIGHBORHOOD and COMMUNITY.)

VISIONING: A method for defining a community's hopes and aspirations through intensive participation at public meetings. WATERSHED: An area of land with a common drainage point.

WETLAND: (See NONTIDAL WETLAND.)

WOODLAND CONSERVATION ORDINANCE: A state and county regulation that seeks to preserve high-priority woodlands through the land development process. It includes the designation and protection of woodland conservation areas, as well as mitigation measures and penalties.

YARD: Open space located on the same lot with a building, structure (not including ground-level paved surfaces unless specifically noted), or use between the building, structure of use (such as outdoor storage) and the nearest lot line or street line. All required yards shall be unoccupied and unobstructed from the ground upward, except for landscaping, accessory buildings, structures, and uses as permitted elsewhere in the Zoning Ordinance.

YARD, FRONT: Yard extending across the width of a lot, between the front street line and the nearest part of a main building (or its enclosed or covered projection).

YARD, REAR: Yard extending across the width of a lot between the rear lot line and the nearest part of a main building (or its enclosed or covered projection).

YARD, SIDE: Yard between the side lot line or side street line and the nearest part of a main building (or its enclosed or covered projection), extending from the front yard to the rear yard.

ZONING: The classification of land by types of uses permitted and prohibited in a district and by densities and intensities permitted and prohibited, including regulations regarding building location on lots.(See EUCLIDEAN ZONES, FLOATING ZONES and COMPREHENSIVE DESIGN ZONE.)

ZONING CATEGORY or DISTRICT: An area designated (zoned) for a type of land use and for a certain density or intensity of development within that type.

ZONING MAP: The official 1"=200' scale map showing the location of all zoning categories in a given area.

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Bow Truss: A wooden rafter made of a bowed truss design. Designed to support roof and ceiling of a standard single wide trailer.

Butyl Tape: A 1/8"x 1"roll type butyl putty used to waterproof roof edges. Installed under roof edge on front and rear and J-rails on sides.

Caulk: A silicone or latex base sealant used over windows, doors, glass in doors, and in siding seams over windows and doors to protect against leakage.

Ceiling: The finish surface of an overhead structure, such as sea spray, gypsum, acoustical.

Clear Span: Reference to a span that does not have intermediate support. In a trailer, a clear span trailer has post at the four corners only, no other support columns along roof beam.

E.P.D.M.: Ethylene, propylene, diene terpolymer membrane. Type of roofing, typical thickness of 45 mil, or 60 mil. The larger the number, the thicker the roofing, the more expensive the roofing.

Galvanized Metal: Typically used in roofing of standard single wide modular buildings. 30 gauge thickness.

Hurricane Straps: 1-1/2"wide galvanized steel straps installed in one long piece over roof and under exterior finish. Attached to tie-downs or anchors. Straps are used to tie unit down against lateral wind load.

Interior Finish: Finish applied to interior ceiling (gypsum, sea spray, acoustical, etc.).

Joist: Horizontal structural member layed on edge to support sheathing.

Mansard: An architectural feature constructed on exterior wall at roof line. Typical mansard is a 24 inch high by 2 inch thick vertical structure with either T-1-11 or vertical aluminum surface.

Mate Beam: Beam constructed along side wall of trailer at a seam line to support roof. Typically constructed from multiple layers of plywood.

Rafter: Structural member to support a roof load. Flat roof rafters are called roof joists.

Roof Beam: A longitudinal structural member designed to carry roof load over spans in trailer. Usually beam consists of laminated, glued and stapled plywood. Number and height of layers depends on span required.

Roofing: Material used for exterior finish of roof such as galvanized metal, rubber roof, EPDM, standing seam)

Rubber Roofing: Type of roof covering that is primarily constructed of single layer of rubber reinforced with fibers.

Sea spray: Pre-finished gypsum sheathing used for ceiling. Typically 3/8" thick.

Sheathing: Layer of flat covering, typically plywood, that spans between roof joists.

Span: The clear horizontal distance between structural supports, as a roof beam spans between two support columns or posts.

Suspended Ceiling: Ceiling consisting of metal frame that supports tiles that rest on frame. Can be 2' by 2' or 2' by 4'. Another name for acoustical ceiling or T-grid ceiling. Provides an acoustical sound reduction, and can be upgraded to meet fire ratings.

True Ceiling: The underside of the roof structure. Typically a finished ceiling is installed below the true ceiling.

Truss: Beams or other supports connected to support a roof. Steel truss is typically a bar joist truss with open web.

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2 x 3: Wood lumber with a measurement of 1-1/2"x 2-1/2”. Comes with designations such as SYP (Southern Yellow Pine), SPF (Pine Fir), and #2 which designate the quality level of the wood. The higher the number the better the wood.

2 x 4: Wood lumber with a measurement of 1-1/2"x 3-1/2”. Comes with designations such as SYP (Southern Yellow Pine), SPF (Pine Fir), and #2 which designate the quality level of the wood. The higher the number the better the wood.

Caulk: A silicone or latex base sealant used over windows, doors, glass in doors, and in siding seams over windows and doors to protect against leakage.

Interior Finish: Finish applied to interior walls (paneling, gypsum, etc.).

Paneling: Interior wall finish, ¼"thick, applied to inside of exterior studs and interior partitions. Standard color is “Williams Birch”.

Trim: Wood or pre-finished moldings that trim out terminations of paneling, vinyl gypsum. See attached sketch for types of moldings.

B.O.B.: Bronze on Bronze. Refers to the tinting of the glass in a double insulated glass door or window. Bronze tint on the exterior, bronze tint glass on the interior.

B.O.C.: Bronze on Clear. Refers to the tinting of the glass in a double insulated glass door or window. Bronze tint on the exterior, clear glass on the interior.

Caulk: A silicone or latex base sealant used over windows, doors, glass in doors, and in siding seams over windows and doors to protect against leakage.

D.I.G.: Double insulated glass. Two layers of glass with air space between them. Better insulating value than standard single pane glass.

H.S.: Horizontal Slider. Standard trailer window. Refers to how the window opens. One half of the window slides over the other half in the horizontal direction.

V.S.: Vertical Slider. Refers to how the window opens. One half of the window slides over the other half in the vertical direction. Requires latches to keep window open.

Double Hung: Typical residential style window. Both halves of the window open by sliding in the vertical direction, but do not require latches to keep open.

Single Hung: Residential style window. Bottom half of window slides open in the vertical direction. Top half is fixed and cannot move. Does not require latch to keep window open.