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Residential Glossary

Air-Conditioning: Cooling and dehumidifying the air in a building using a refrigeration unit driven by electricity or natural gas. This definition excludes fans, blowers, or evaporative cooling systems ("swamp coolers") that are not connected to a refrigeration unit. Air-conditioning units that are not currently in working condition or are not used are included if they are in place in the housing unit. (See Refrigeration Unit.)

Air-Conditioning Equipment: A system, either a central system or window or wall units, that cools the air in a housing unit using a refrigeration unit driven by electricity or natural gas. Excluded are fans, blowers, or evaporative cooling systems ("swamp coolers") that are not connected to a refrigeration unit. Air-conditioning units that were not in working condition or were not used are still included in RECS if they are in place in the housing unit. Some central air-conditioners are heat pumps.

Apartments in Buildings with 2 to 4 Units: A unit in a building with two to four housing units--a structure that is divided into living quarters for two, three, or four families or households and in which one household lives above another. This category also includes houses originally intended for occupancy by one family (or for some other use) that have since been converted to separate dwellings for two to four families. Typical arrangements in these types of living quarters are separate apartments downstairs and upstairs or one apartment on each of three or four floors.

Apartments in Buildings with 5 or More Units: A unit in a building with five or more housing units--a structure that contains living quarters for five or more households or families and in which one household lives above another

Appliances: Appliances used in the home during the year, including those loaned to the householder for regular use. Appliances possessed by the household but not used are not counted, except for air- conditioning equipment. Appliances temporarily not in working condition but generally used by the household are included only if a repair person has been called or the appliance has been taken to a repair shop.

Authorization Form: The one-page form signed by the respondent that gives permission to the energy supplier to release information about the energy used in the housing unit. The form contains the name of each energy supplier.

Automatic Set-Back or Clock Thermostat: A thermostat that can be set to turn the heating/cooling system off and on at certain predetermined times.

Average: The simple arithmetic average for a population; that is, the sum of all the values in a population divided by the size of the population. Population means are estimated by computing the weighted sum of the sample values, then dividing by the sum of the sample weights. (See Weight.)

Basement: An enclosed space in which a person can walk upright under all or part of the building.

Bathroom: A full bathroom contains a sink with running water, a flush toilet, and a bathtub or shower. A half bathroom contains a toilet or bathtub or shower.

Bedroom: Room intended for sleeping. If not presently used for sleeping, number of bedrooms are those that would be listed as descriptive of the apartment or house if it were on the market for sale or rent. A one-room efficiency or studio apartment has no bedrooms.

Bottled Gas: See Liquefied Petroleum Gas.

Built-In Electric Units: An individual-resistance electric-heating unit that is permanently installed in the floors, walls, ceilings, or baseboards and is part of the electrical installation of the building. Electric space-heating devices that are plugged into an electric socket or outlet are not considered built in. (See Heating Equipment and Portable Electric Heater.)

Cash and Carry: Kerosene, fuel oil, or bottled gas (tank or propane) purchased with cash, check, or credit card and taken home by the purchaser. The purchaser provides the container or pays extra for the container.

CDD: See Cooling Degree-Days (CDD).

Ceiling Fan: Fans, installed on the ceiling, used to ventilate a room.

Census Division: A geographic area consisting of several States defined by the U.S. Department of Commerce, Bureau of the Census. (See the Census region and division map.) The States are grouped into four regions and nine divisions:

Region Division

States

Northeast

New England

Connecticut, Maine, Massachusetts, New Hampshire, Rhode Island, and Vermont
Middle Atlantic New Jersey, New York, and Pennsylvania
Midwest East North Central Illinois, Indiana, Michigan, Ohio, and Wisconsin
West North Central Iowa, Kansas, Minnesota, Missouri, Nebraska, North Dakota, and South Dakota
South South Atlantic Delaware, the District of Columbia, Florida, Georgia, Maryland, North Carolina, South Carolina, Virginia, and West Virginia
East South Central Alabama, Kentucky, Mississippi, and Tennessee
West South Central Arkansas, Louisiana, Oklahoma, and Texas
West Mountain Arizona, Colorado, Idaho, Montana, Nevada, New Mexico, Utah, and Wyoming
Pacific Alaska, California, Hawaii, Oregon, and Washington.

Census Region: See Census Division and the Census region and division map.

Central Air-Conditioning: See Air-Conditioning Equipment.

Central City: Usually one or more legally incorporated cities within the Metropolitan Statistical Area (MSA) that is significantly large by itself or large relative to the largest city in the MSA. Additional criteria for being classified "central city" include having at least 75 jobs for each 100 employed residents and having at least 40 percent of the resident workers employed within the city limits. Every MSA has at least one central city, which is usually the largest city. Central cities are commonly regarded as relatively large communities with a denser population and a higher concentration of economic activities than the outlying or suburban areas of the MSA. "Suburban" are those parts of the MSA that are not designated as central city. (See Metropolitan Statistical Area (MSA), Rural, Suburban, and Urban.)

Central Warm-Air Furnace: A type of space-heating equipment in which a central combustor or resistance unit--generally using gas, fuel oil, or electricity--provides warm air that circulates through ducts leading to the various rooms. Heat pumps are not included in this category. A forced-air furnace is one in which a fan is used to force the air through the ducts. In a gravity furnace, air is circulated by gravity, relying on the natural flow of warm air up and cold air down; the warm air rises through ducts and the cold air falls through ducts that return it to the furnace to be reheated, thus completing the circulation cycle. (See Heating Equipment.)

City: Classification based on interviewer judgment, not on characteristics of the county where the area is found. (See Observed Location of Household.)

Climate Zone: One of five climatically distinct areas, defined by long-term weather conditions affecting the heating and cooling loads in buildings. The zones were developed by the Energy Consumption Division (ECD) from seven distinct climate categories originally identified by the American Institute of Architects (AIA) for the U.S. Department of Energy and the U.S. Department of Housing and Urban Development. The zones were determined according to the 30-year average (1961-1990) of the annual heating and cooling degree-days (base 65 degrees Fahrenheit). The zones are defined as follows:

ECD
AIA
Zone
Climate
Zone
Average Annual
Cooling
Degree-Days
Average Annual
Heating
Degree-Days
1


2


3


4


5


6


7

1


2


3


4


4


5


5

Less than 2,000

Less than 2,000

Less than 2,000

Less than 2,000

Less than 2,000

2,000 or More

2,000 or More

More than 7,000


5,500 to 7,000


4,000 to 5,499


2,000 to 3,999


Less than 2,000


Less than 2,000


2,000 to 3,999

An individual household was assigned to a climate zone according to the 30-year average annual degree-days for an appropriate nearby weather station. (See Heating Degree-Days [CDD] and Cooling Degree-Days [CDD].)

Clothes Dryer: An appliance that dries laundry through the application of heat and rapid air movement. The hot air used is typically heated by electricity or gas (either natural gas or liquefied petroleum gas). (See Appliances.)

Clothes Washer: An appliance for automatically cleaning home laundry. It has an opening on its top or its front offering access to the washer tub. An agitator, located within the tub, moves the articles to be cleaned through the wash water. The machine is powered by an electric motor connected to the tub and agitator via a transmission, clutches, and linkages. In front-loading machines, the articles are moved by a rotating tub rather than an agitator. (See Appliances.)

Coal: A combustible mineral substance (carbonized vegetable matter). In this report, the term includes its derivative, coke, which is formed by destructive distillation or imperfect combustion. Only statistics on the number of households using coal are collected in RECS. (See Fuel.)

Condominium: A type of ownership that enables a person to own an apartment or house in a project of similar units. The owner has his/her own deed and, most likely, his/her own mortgage on the unit. The owner also holds a common or joint ownership in all common areas, such as hallways, entrances, andelevators. Ownership may cover single-family houses, including row houses and townhouses, as well as apartments.

Condo Fee: In condominiums, the fee paid to the homeowners association for maintenance, management, insurance, and, in some cases, utilities.

Control Total: The number of elements in the population or a subset of the population. The sample weights for the observed elements in a survey are adjusted so that they add up to the control total. The value of a control total is not obtained from the survey; it is obtained from an outside source. For the RECS, the control totals were obtained from the Current Population Survey. (See Appendix A, "How the Survey Was Conducted.")

Cooking Stove: A stove built for preparing food. In this survey, it may also be used as the main heating equipment. (See Heating Equipment and Appliances.)

Cooling Degree-Days (CDD): A measure of how hot a location was over a period of time, relative to a base temperature. In this report, the base temperature is 65 degrees Fahrenheit, and the period of time is 1 year. The number of cooling degree-days for a single day is the difference between that day's average temperature and the base temperature, if the daily average is greater than the base; it is zero if the daily average temperature is less than or equal to the base temperature. The number of cooling degree-days for a longer period of time is the sum of the daily cooling degree-days for the days in that period. Annual cooling degree-days averaged over 30 years from 1961 to 1990 are called Normal Cooling Degree-Days. Average daily temperature is the mean of the maximum and minimum temperatures for a 24-hour period. Cooling degree-days can also be calculated using a base temperature other than 65 degrees. The computation is performed in an analogous manner. (See Heating Degree-Days [HDD] and Climate Zone.)

Cooperative: A type of ownership where a group of housing units are owned by a corporation of member-owners. Each individual member is entitled to occupy an individual housing unit and is a shareholder in the corporation that owns the property. Ownership may cover single-family houses, row houses, and townhouses, as well as apartments.

Crawl Space: Space between the ground and the floor of a house in which a person cannot walk upright. An enclosed crawl space is one not accessible from the outside of the house (except by a door or window) because the walls of the space protect it from the weather. A crawl space "open to the outside" is one that is accessible from outside the house--even though it may be covered by a trellis or lathwork, or some kind of brickwork that leaves space for circulation of air.

Dishwasher: A built-in or portable appliance used for automatically cleaning dishware, utensils, and cutlery. The national appliance efficiency standards required that, by 1988, dishwashers be equipped with an option to dry without heat. (See Appliances.)

Electric Pump for Well Water: A pump that forces the water from a well below ground level up into the water pipes that circulate through the house. When this pump is not working, there is a limited supply of running water in the house. (See Appliances.)

Electricity: Metered electric power supplied by a central utility company to a residence via underground or aboveground power lines. Electricity generated on site for the exclusive use of a residence is estimated using the regression equations used to impute electricity. Since there are no volumetric measures of electricity as with the fossil fuels, electricity is measured as the amount of power used at any instant (demand expressed in W or kW) or as power used over a given time (consumption expressed in kWh). The heat equivalent for electricity that comes into the home is 3,412 Btu per kWh, but this is a derived form of energy and does not represent the amount of energy needed to generate the electricity and transmit it to the building. Generation and transmission requires about 3.3 times 3,412 Btu per kWh, or 11,620 Btu per kWh.

Eligible for Federal Assistance: Households are categorized as eligible for Federal energy assistance if their income is below the Federal maximum standard. The Federal standard is 150 percent of the poverty line or 60 percent of Statewide median income, whichever is the higher income. Individual States can set the standard at a lower level than the Federal maximum. (See Poverty Line.)

Energy Assistance Program: See Low-Income Home Energy Assistance Program (LIHEAP).

Energy Source: A type of energy or fuel consumed by the household. For this report, the energy sources identified are electricity, natural gas, fuel oil, kerosene, liquefied petroleum gas (propane), wood, coal, and solar energy. (See Electricity, Natural Gas, Fuel Oil, Kerosene, Liquefied Petroleum Gas [LPG], Wood, Coal, and Solar Energy.)

Energy Supplier: Fuel companies supplying electricity, natural gas, fuel oil, kerosene, or LPG to the household. (See Authorization Form and Appendix A, "How the Survey Was Conducted.")

Facsimile Machine (FAX): Equipment that transmits and receives printed material over telephone lines. (See Appliances.)

Fireplace: Usually a masonry unit that burns wood, is built into the wall of a house, and has a permanent chimney. Fireplaces in mobile homes are included. Fireplaces may have glass doors or metal shields to cover the opening into the room. Accessories, such as convective grates or radiant grates, may be present to increase the efficiency of the fireplace. Included are fireplaces that use equipment fueled by natural gas or LPG. These gas fireplaces may or may not have a flue to the outside. A free-standing fireplace that can be detached from its chimney is a heating stove. (See Heating Equipment and Heating Stove Burning Wood, Coal or Coke.)

Floor, Wall, or Pipeless Furnace: Space-heating equipment consisting of a ductless combustor or resistance unit, having an enclosed chamber where fuel is burned or where electrical-resistance heat is generated to warm the rooms of a building. A floor furnace is located below the floor and delivers heated air to the room immediately above or (if under a partition) to the room on each side. A wall furnace is installed in a partition or in an outside wall and delivers heated air to the rooms on one or both sides of the wall. A pipeless furnace is installed in a basement and delivers heated air through a large register in the floor of the room or hallway immediately above. (See Heating Equipment.)

Freezer: A cabinet designed as a unit for storing food at temperatures of about 0 degrees Fahrenheit and having a refrigeration unit driven by an electric motor. It is a separate appliance, not part of the refrigerator, and can be an upright model (vertical cabinet with the door opening outward) or a chest model (horizontal cabinet with the door opening upward). (See Appliances.)

Frost-Free: A freezer either separate from or within a refrigerator that automatically defrosts itself every 12 or 24 hours.

Fuel: A fuel or energy source delivered to a residential site. It may be converted to some other form of energy at the site. Electricity is included as a fuel. Other fuels are coal, fuel oil, kerosene, liquefied petroleum gas (LPG), natural gas, wood, and solar.

Fuel Oil: No. 1, No. 2, or No. 4 grade fuel oil or residual oil that is burned for space- or water-heating purposes. No. 1 distillate fuel oil is used mostly as a blending stock to assure that heavier grades of fuel flow under severe cold weather conditions. No. 2 fuel oil is the most common form of heating oil. No. 2 distillate collectively refers to No. 2 heating oil and No. 2 diesel fuel. Although these products are not precisely identical, they are essentially interchangeable in most applications. No. 4 distillate is a blend of No. 2 and No. 5 or No. 6 residual fuel oil, used in large, stationary diesel engines and boilers equipped with fuel preheating equipment. (See Fuel.)

Furnace: That part of a boiler or warm-air space-heating plant in which combustion takes place. (See Heating Equipment.)

Garage: A space large enough to accommodate a car, with a door opening at least 6 feet wide and 7 feet high.

Gas Air-Conditioning: Cooling and dehumidification of the air in a building by a refrigeration unit driven by gas (either natural gas or LPG). Such units are extremely rare. (See Refrigeration Unit.)

Group Quarters: Living arrangements for institutional groups containing 10 or more unrelated persons. They are excluded from the RECS. Group quarters are typically found in hospitals, nursing or rest homes, military barracks, ships, halfway houses, college dormitories, fraternity and sorority houses, convents, monasteries, shelters, jails, and correctional institutions. Group quarters may also be found in houses or apartments shared by 10 or more unrelated persons. Group quarters are often equipped with a common dining area for residents. (See Housing Unit.)

HDD: See Heating Degree-Days (HDD).

Heat Pump (Reverse-Cycle System): A year-round heating and air-conditioning system in which refrigeration equipment supplies both heating and cooling through ducts leading to individual rooms. A heat pump generally consists of a compressor, both indoor and outdoor coils, and a thermostat. In the RECS, all heat pumps are considered to be electric. (See Heating Equipment.)

Heated: A room or space warmed by space-heating equipment. Basements and other areas where the space-heating equipment or heating ducts are located may be considered heated if they are warm enough to sit, work, or play in during the winter months. If a housing unit has no space-heating equipment, then there are no heated areas in the housing unit.

Heated Aquarium: A tank, used as a container for fish, that holds 20 or more gallons of heated water and is usually made of glass. A 20-gallon tank is approximately 30 inches by 12 inches by 12 inches.

Heated Floorspace (estimated): In this survey (1997), the heated floor area of the housing unit as estimated by the respondent. In past surveys, the floorspace was measured by the interviewer.

Heating Degree-Days (HDD): A measure of how cold a location was over a period of time, relative to a base temperature. In this report, the base temperature used is 65 degrees Fahrenheit and the period of time is 1 year. The number of heating degree-days for a single day is the difference between the base temperature and the day's average temperature, if the daily average is less than the base; it is zero if the daily average temperature is greater than or equal to the base temperature. The number of heating degree-days for a longer period of time is the sum of the daily heating degree-days for days in that period. Annual heating degree-days averaged over 30 years from 1961 to 1990 are called Normal Heating Degree-Days. Average daily temperature is the mean of the maximum and minimum temperatures for a 24-hour period. Heating degree-days can also be calculated using a base temperature other than 65 degrees. The computation is performed in an analogous manner. (See Cooling Degree-Days [CDD] and Climate Zone.)

Heating Equipment: The equipment used for heating ambient air in the housing unit, such as: central warm-air furnace, heat pump, built-in electric units, steam or hot-water system, floor, wall, or pipeless furnace, heating stove, room heater, fireplace, or portable heater. The main space-heating equipment is reported as such even if it is temporarily out of order. A "cooking stove" may be used as the mainspace-heating equipment even though it was built for preparing food. (See descriptions of specific types of space-heating equipment: Central Warm-Air Furnace; Heat Pump [Reverse-Cycle System]; Built-In Electric Units; Steam or Hot-Water System; Floor, Wall, or Pipeless Furnace; Heating Stove Burning Wood, Coal, or Coke; and Room Heater Burning Gas, Oil, or Kerosene.)

Heating Stove Burning Wood, Coal, or Coke: Any free-standing box or controlled-draft stove; or a stove installed in a fireplace opening, using the chimney of the fireplace. Stoves are made of cast iron, sheet metal, or plate steel. Free-standing fireplaces that can be detached from their chimneys are considered heating stoves. (See Heating Equipment.)

Hispanic Descent: Determined by the respondent, as was the question on origin. The respondent was asked, "Is the householder of Spanish or Hispanic origin or descent?" and the respondent's answer was recorded.

Hot-Deck Imputation: A statistical procedure for deriving a probable response to a questionnaire item concerning a household, for which a response is missing. To perform the procedure, an analyst sorts the households by variables related to the missing item. Thus, a series of sort categories are formed, which are internally homogeneous with respect to the sort variables. Within each category, households for which the questionnaire item is not missing are randomly selected to serve as "donors" to supply values for the missing item of "recipient" households. (See Imputation and Appendix A, "How the Survey Was Conducted.")

Hot Tub: A water-filled wood, plastic, or ceramic container in which up to 12 people can lounge. Normally equipped with a heater that heats the water from 80 to 106 degrees Fahrenheit. It may also have jets to bubble the water. The water is not drained after each use. An average-size hot tub holds 200 to 400 gallons of water. All reported hot tubs were assumed to include an electric pump. Hot tubs are also called Spas or Jacuzzis. (See Appliances.)

Household: A family, an individual, or a group of up to nine unrelated persons, occupying the same housing unit. "Occupy" means the housing unit was the person's usual or permanent place of residence at the time of the first field contact. Household members include babies, lodgers, boarders, employed persons who live in the housing unit, and persons who usually live in the household but are away traveling or in a hospital. Not included in the household are: 1) persons who are normally members of the household but who were away from home as collge students or members of the armed forces at the time of the interview; 2) persons temporarily visiting with the household if they have a place of residence elsewhere; 3) persons who take their meals with the household, but usually lodge or sleep elsewhere; 4) domestic employees or other persons employed by the household who do not sleep in the same housing unit; 5) or former members of the household who have become inmates of correctional, penal, or mental institutions, homes for the aged or needy, nursing homes, hospitals, hospices, convents or monasteries, or other places in which residents may remain for long periods of time. By definition, in the RECS, the number of households is the same as the number of occupied primary housing units. (See Primary Residence.)

Household Income Category: The income grouping for the total combined income (before taxes and deductions) of all members of the household from all sources, for the 12 months prior to the interview. Sources of income include the following: wages, salaries, tips, commissions, interest, dividends, rental income, Social Security or railroad retirement, pensions, food stamps, Aid to Families with Dependent Children, unemployment compensation, Supplemental Security Income, General Assistance, and other public assistance. This definition includes the total income of all household members who lived in the household during the 12 months prior to the interview, regardless of whether they were living there at the time of the interview.

Household Member: See Household.

Householder: The person (or one of the people) in whose name the home is owned or rented. If there is no lease or similar agreement, or if the person who owns the home or pays the rent does not live in the housing unit, the householder is the person responsible for paying the household bills, or whoever is generally in charge.

Housing Unit: A house, an apartment, a group of rooms, or a single room if it is either occupied, or intended for occupancy, as separate living quarters by a family, an individual, or a group of one to nine unrelated persons. Separate living quarters means the occupants (1) live and eat separately from other persons in the house or apartment and (2) have direct access from the outside of the building or through a common hall--that is, they can get to it without going through someone else's living quarters. Housing units do not include group quarters where 10 or more unrelated persons live. Hotel and motel rooms are considered housing units if occupied as the usual or permanent place of residence. (See Primary Residence, Group Quarters, Year-Round Unit, Seasonal Unit, and Migratory Unit.)

Housing Unit Record Sheet: A form (pink sheet) completed by interviewers for each housing unit assigned for contact. The type of housing unit is recorded, as well as information about each visit.

Imputation: A statistical method used to fill in values for missing items, designed to minimize the bias of estimates. (See Hot-Deck Imputation and Appendix A, "How the Survey Was Conducted.")

Jacuzzi: See Hot Tub.

Kerosene: A distilled product of oil or coal with the generic name kerosene, having properties similar to those of No. 1 fuel oil. It is sometimes sold under the names "range oil," "stove oil," or "coal oil." (See Fuel.)

Laser Printer for Computer (not dot matrix): A computer printer that uses toner, a black powder, for the printer's ink. It provides high quality printing. (See Appliances.)

LIHEAP: See Low-Income Home Energy Assistance Program.

Liquefied Petroleum Gas (LPG): Any fuel gas, such as propane or butane, supplied to a residence in liquid form. It is usually delivered by tank truck and stored near the residence in a tank or cylinder until used. Propane was the most common liquefied petroleum gas supplied to RECS households. (See Fuel.)

Low-Income Home Energy Assistance Program (LIHEAP): The purpose of LIHEAP is to assist eligible households to meet the cost of heating or cooling in residential dwellings. The Federal government provides the funds to the States that administer the program.

LPG: See Liquefied Petroleum Gas (LPG).

Main: Used most, as in "Main Heating Equipment," which is the equipment used most for space heating. (See Used Most.)

Master-Metering: Measurement of electricity or natural gas consumption of several tenants or housing units using a single meter. That is, one meter measures the energy usage for several households collectively. RECS identifies households that pay their own fuel bills, but does not specifically identify a household as "master metered."

Mean Indoor Temperature: The "usual" temperature inside the housing unit. If different sections of the house are kept at different temperatures, the reported temperature is for the section where the people are. A thermostat setting is accepted if the temperature is not known.

Metropolitan: See Urban.

Metropolitan Statistical Area (MSA): Areas defined by the U.S. Office of Management and Budget in 1992. An MSA is (1) a county or group of contiguous counties that contain at least one city of 50,000 inhabitants or more, or (2) an urbanized area of at least 50,000 inhabitants and a total MSA population of at least 100,000 (75,000 in New England). The contiguous counties are included in an MSA if, according to certain criteria, they are essentially metropolitan in character and are socially and economically integrated with the central city. In New England, MSA's consist of towns and cities, rather than counties. (See Central City, Rural, Suburban, and Urban.)

Microwave Oven: A household cooking appliance consisting of a compartment designed to cook or heat food by means of microwave energy. It may also have a browning coil and convection heating as additional features. (See Appliances.)

Migratory Unit: Housing unit intended for occupancy by migratory workers employed in farm work during the crop season. It is usually excluded from the RECS, since it is not often the primary residence for more than 6 months of the year. (See Primary Residence.)

Mobile Home: A housing unit built on a movable chassis and moved to its site. It may be placed on a permanent or temporary foundation and may contain one room or more. If rooms are added to the structure, it is considered a single-family housing unit. A manufactured house assembled on site is a single-family housing unit, not a mobile home.

Modem: A device connecting a personal computer to a telephone line that permits communication with computers or other devices outside the housing unit.

MSA: See Metropolitan Statistical Area (MSA).

Multistage Area Probability Sample: A sample design executed in stages with geographic "clusters" of sampling units selected at each stage. This procedure reduces survey expense while maintaining representative national coverage. (See Appendix A, "How the Survey Was Conducted.")

Natural Gas: Hydrocarbon gas (mostly methane) supplied as an energy source to individual buildings by pipelines from a central utility company. Natural gas does not refer to liquefied petroleum gas. A few households were supplied by a privately owned gas well.

Nonmetropolitan: See Rural.

Normal Degree-Days: Annual cooling or heating degree-days averaged over 30 years (from 1961 to 1990). (See Cooling Degree-Days [CDD] and Heating Degree-Days [HDD].)

Observed Location of Household: A judgment made by the interviewer at the time the interviewer visited the area to conduct the interview. The four categories were city, town, suburbs, and rural or open country. (Compare with Urban Status.)

Occupied Housing Unit: A unit in which someone was living as his or her usual or permanent place of residence at the time of the interviewer's first visit to the unit. (See Housing Unit.)

Origin: The primary ethnic background of the person considered to be the householder as determined by the respondent. Each respondent was asked, "Which of the groups on this exhibit best describes the householder?" The groups included: white, black or Afro-American, Native American, Alaskan native, Asian, and Pacific Islander. The word "race" was not used in either the questionnaire or the instructions.

Outside Central City: See Suburban.

Oven: An appliance that is an enclosed compartment supplied with heat and used for cooking food. Toaster ovens are not considered ovens. The range stove top or burners and the oven are considered two separate appliances, although they are often purchased as one appliance. (See Appliances.)

Owned/Rented: The relationship of a housing unit's occupants to the structure itself, not the land on which the structure is located. "Owned" means the owner or co-owner is a member of the household and the housing unit is either fully paid for or mortgaged. A household is classified "rented" even if the rent is paid by someone not living in the unit. "Rent free" means the unit is not owned or being bought and no money is paid or contracted for rent. Such units are usually provided in exchange for services rendered or as an allowance or favor from a relative or friend not living in the unit. Unless shown separately, rent-free households are grouped with rented households.

Ownership: See Owned/Rented.

Personal Computer: A microcomputer for producing written, programmed, or coded material, playing games, or doing calculations; included as an appliance in RECS. Laptop and notebook computers are excluded. (See Appliances.)

Pink Sheet: See Housing Unit Record Sheet.

Portable Electric Heater: A heater that uses electricity and that can be picked up and moved.

Portable Kerosene Heater: A heater that uses kerosene and that can be picked up and moved.

Poverty Line: Low-income classifications to which certain households are assigned. "Below 100 percent of poverty" encompasses a group of households with incomes below the poverty level as defined by the U.S. Bureau of the Census and the Office of Management and Budget. "Below 125 percent of poverty" includes a group of households with incomes below 125 percent of the poverty level. These groups of the poor and near-poor represent alternative levels for defining poverty. The poverty line varies with the number of family members in the household and the income of the entire family. (See Eligible for Federal Assistance.)

Primary Energy Consumption: Primary energy consumption is the amount of site consumption, plus losses that occur in the generation, transmission, and distribution of energy (See Site Energy Consumption.).

Primary Residence: A housing unit in which a householder spends the largest part of the calendar year; it is the householder's usual or permanent residence. This would normally be a year-round housing unit. It would generally exclude migratory and seasonal units. However, if a seasonal unit happened to be occupied for half of the year or more by the householder, that unit would be considered the primary residence. (See Householder, Housing Unit, Migratory Unit, Seasonal Unit, Year- Round Unit, and Second Home.)

Primary Sampling Unit (PSU): A sampling unit selected at the first stage in multistage area probability sampling. A PSU typically consists of one to several contiguous counties--for example, a metropolitan area with surrounding suburban counties. (See Appendix A, "How the Survey Was Conducted.")

Propane: See Liquefied Petroleum Gas (LPG).

PSU: See Primary Sampling Unit (PSU).

Public Housing: Housing units owned by a local housing authority or other local public agency, such as a housing and redevelopment authority or a housing development agency. These organizations receive subsidies from the Federal or State governments, but the local agency owns the property. To live in such a project, one must apply to the local housing authority.

Race: See Origin.

Radiator: A heating unit usually exposed to view within the room or space to be heated; it transfers heat by radiation to objects within visible range and by conduction to the surrounding air, which in turn is circulated by natural convection; it is usually fed by steam or hot water. (See Heating Equipment.)

Range: The range burners or stove top and the oven are considered two separate appliances. Counted also with range tops are stand-alone "cook tops." (See Appliances.)

Refrigeration Unit: Lowers the temperature through a mechanical process. By definition, refrigerators, freezers, and air-conditioning equipment all contain refrigeration units.

Refrigerator: A cabinet designed for cooling food at temperatures above 32 degrees Fahrenheit. Most also have a second compartment for freezing and storing frozen foods at temperatures of 8 degrees Fahrenheit or below. (See Appliances.)

Relative Standard Error: See RSE (Relative Standard Error).

Renewable Energy: Energy obtained from sources that are essentially inexhaustible (unlike, for example, the fossil fuels, of which there is a finite supply). Renewable sources of energy include wood, waste, geothermal, wind, photovoltaic, and solar thermal energy.

Rent: See Owned/Rented.

Residential: Occupied housing units, including mobile homes, single-family housing units (attached and detached), and apartments. Residential does not include vacant housing units or second homes. The definition of "occupied housing units" is the same as that used by the U.S. Bureau of the Census. (See Household and Housing Unit.)

Residential Energy Consumption Survey (RECS): A national multistage probability sample survey conducted by the Energy Consumption Division of the Energy Information Administration. The RECS provides baseline information on how households in the United States use energy.

Room Air-Conditioner: Air-conditioning units that typically fit into the window or wall and are designed to cool only one room. (See Appliances and Air-Conditioning Equipment.)

Room Heater Burning Gas, Oil, or Kerosene: Any of the following heating equipment: circulating heaters, convectors, radiant gas heaters, space heaters, or other nonportable room heaters that may or may not be connected to a flue, vent, or chimney. (See Heating Equipment.)

Rooms: Subdivisions of a living unit. Whole rooms are rooms such as living rooms, dining rooms, bedrooms, kitchens, lodgers' rooms, finished basements or attic rooms, recreation rooms, and permanently enclosed sun porches that are used year-round. Rooms used for offices by a person living in the unit are included. "Finished" means that the ceiling and walls are covered with finishing materials.

Not considered to be rooms are bathrooms, halls, foyers, or vestibules, balconies, closets, alcoves, pantries, strip or pullman kitchens, laundry or furnace rooms, unfinished attics or basements, open porches, and unfinished space used for storage.

A partially divided room, such as a dinette next to a kitchen or a living room, is considered a separate room only if there is a partition from floor to ceiling--but not if the partition consists solely of shelves or cabinets. If a room is used by occupants of more than one unit, the room is included with the unit from which it is most easily reached. (See Bedroom and Bathroom.)

RSE Column Factor: An adjustment factor that appears above each column of the published tables and is used to compute RSE's. For a survey estimate in a particular row and column of a table (that is, a particular "cell"), the approximate RSE is obtained by multiplying the RSE row factor by the RSE column factor for that cell. (See RSE or Relative Standard Error, RSE Row Factor, and the "Generalized Variances" section of Appendix B, "Survey Estimates and Data Quality.")

RSE or Relative Standard Error: A measure of the reliability or precision of a survey statistic on a percentage scale. Variability occurs in survey statistics because the different samples that could be drawn would each produce different values for the survey statistics. The RSE is defined as the standard error of a survey estimate, divided by the survey estimate, then multiplied by 100. (Standard error is the square root of the variance.) For example, an RSE of 50 percent means that the standard error is half as large as the survey estimate. (See Appendix B, "Survey Estimates and Data Quality.")

RSE Row Factor: A factor that appears to the right of each row of the published tables and is used to compute RSE's. For a survey estimate in a particular row and column of a table (that is, a particular "cell"), the approximate RSE is obtained by multiplying the RSE row factor by the RSE column factor for that particular cell. The row factor is equal to the geometric mean of the RSE's in a particular row of the tables. (See RSE or Relative Standard Error, RSE Column Factor, and the "Generalized Variances" section of Appendix B, "Survey Estimates and Data Quality.")

Rural: Households not located within Metropolitan Statistical Areas as defined by the U.S. Office of Management and Budget for 1993. (See Metropolitan Statistical Area (MSA), Central City, Suburban, and Urban.)

Rural or Open Country: Classification based on interviewer judgment, not based on characteristics of the county where the area is found. (See Observed Location of Household.)

Sampling: The procedure used to select housing units for interview from the population of all residential housing units in the United States. (See Multistage Area Probability Sample and Appendix A, "How the Survey Was Conducted.")

Seasonal Unit: Housing unit intended for occupancy at only certain seasons of the year. Seasonal unit includes units intended only for recreational use, such as beach cottages and hunting cabins. It is not likely that this type of unit will be the usual residence for a household, since it may not be fit for living quarters for more than half of the year. (See Primary Residence.)

Secondary Heating Equipment: Space-heating equipment used less often than the main space-heating equipment. (See Main.)

Secondary Heating Fuel: Fuel used in secondary space-heating equipment.

Second Home: By definition, a second home is not the primary residence of a householder. Second homes are not included in the RECS count of occupied housing units. (See Housing Unit, Primary Residence, and Seasonal Unit.)

Setback Temperature Behavior: These data were derived from differences in the temperature settings reported by respondents for their daytime temperature when someone is at home, daytime temperature when no one is at home, and the temperature for sleeping hours (assumed to be nighttime). For example, if a respondent's reported temperature setting was lower when no one was at home than when someone was at home, respondents were assumed to be "setting back" the temperature.

Single-Family: A unit that provides living space for one household or family. The structure may be detached or attached to another unit. Attached houses are considered single-family houses as long as the house itself is not divided into more than one housing unit and has an independent outside entrance. A single-family house is contained within walls extending from the basement (or the ground floor, if there is no basement) to the roof. (A mobile home with one or more rooms added is classified as a single-family home.) Townhouses, rowhouses, and duplexes are considered single-family attached housing units, as long as there is no household living above another one within the walls that go from the basement to the roof to separate the units.

Site Energy Consumption: The Btu value of energy at the point it enters the home, building, or establishment, sometimes referred to as "delivered" energy. (See Primary Energy Consumption.)

Solar Energy: The radiant energy of the sun, which can be converted into other forms of energy, such as heat or electricity.

Spa: See Hot Tub.

Space Heating: The use of energy to generate heat for warmth in housing units using space-heating equipment. The equipment could be the main space-heating equipment or secondary space-heating equipment. It does not include the use of energy to operate appliances (such as lights, televisions, and refrigerators) that give off heat as a byproduct. (See Heating Equipment, Heated, and Heated Floorspace [estimated]).

Space-Heating Equipment: See Heating Equipment.

Square Feet: See Heated Floorspace (estimated).

Steam or Hot-Water System: Either of two types of a central space-heating system that supplies steam or hot water to radiators, convectors, or pipes. The more common type supplies either steam or hot water to conventional radiators, baseboard radiators, convectors, heating pipes embedded in the walls or ceilings, or heating coils or equipment that are part of a combined heating/ventilating or heating/air-conditioning system. The other type supplies radiant heat through pipes that carry hot water and are inlaid in a concrete slab floor. (See Heating Equipment.)

Stories: Floors or levels in a building, not including basements. When the building is a split level, the larger number of stories is used.

Stove: See Heating Stove Burning Wood, Coal, or Coke and Cooking Stove.

Structure: One of four categories used to categorize the building in which the housing unit was located. For the RECS, the categories were single-family, multifamily (two to four units), multifamily (five or more units), and mobile home. (See Single-Family, Multifamily two to four units, Multifamily five or more units, and Mobile Home.)

Suburban: Those parts of the MSA that are not designated as central city. Suburban areas are referred to as "outside central city." (See Metropolitan Statistical Area (MSA), Central City, Rural, and Urban.)

Suburbs: Classification based on interviewer judgment, not based on characteristics of the county where the area is found. (See Observed Location of Household.)

Swimming Pool Heater: Optional heating equipment that heats the pool water to an acceptable level of comfort, usually 80 to 85 degrees Fahrenheit. (See Appliances.)

Swimming Pool Pump: An electric pump for filtering and circulating the water.

Telecommuting: Using a personal computer that is connected by a modem to a site outside the housing unit where a member of the household is employed. Instead of commuting to a place of employment, the household member works at home using a personal computer.

Temperature: Household-reported estimates of the indoor temperature. If different sections of the house are kept at different temperatures, the temperature requested is for the part of the house being used. If the heat is turned off upstairs during the day because the family is downstairs, the downstairs temperature is used. If the temperature is unknown, the thermostat setting is used.

Thermostat: A device that adjusts the amount of heating and cooling produced and/or distributed by automatically responding to the temperature in the environment.

Toaster Oven: Portable table-top appliance used for heating or broiling food. It is not included under oven in this survey.

Town: Classification based on interviewer judgment, not based on characteristics of the county where the area is found. (See Observed Location of Household.)

Transported Gas: Natural gas physically delivered to a building by a utility but not bought from that utility. A separate transaction is made to purchase the volume of gas and the utility is paid for the use of its pipeline to deliver the gas.

Urban: Urban refers to a group of households located within the Metropolitan Statistical Area (MSA) as defined by the U.S. Office of Management and Budget in 1993. For this report, urban is composed of central city and suburban areas. (See Metropolitan Statistical Area (MSA), Central City, Rural, and Suburban.)

Urban Status: Refers to geographic location of the households based on Federal Government definitions of Metropolitan Statistical Area (MSA) for 1993. (See Metropolitan Statistical Area (MSA), Central City, Rural, Suburban, and Urban.)

Used Most: Used more days in the year. When two or more fuels are used for the same purpose (such as to heat water or heat a swimming pool), the fuel used more days is the one "used most." When the household uses more than one refrigerator, freezer, or window/wall air-conditioning unit, the one used more days is the one "used most." If a decision could not be made on the basis of days used, respondents chose the one used more intensely.

Vacant Housing Unit: A housing unit not occupied when the first RECS field contact was made. An occupied seasonal or migratory housing unit is classified as vacant at the time of the first contact if all of its occupants had a usual place of residence elsewhere.

Water-Bed Heater: An appliance that uses an electric resistance coil to maintain the temperature of the water in a water bed at a comfortable level. (See Appliances.)

Water Heated by a Space-Heating System: Some heating systems provide hot water as well as heat the home. The water is heated in a coil that is part of the heating system. There is no separate hot water tank for these systems.

Water Heater: An automatically controlled, thermally insulated vessel designed for heating water and storing heated water at temperatures less than 180 degrees Fahrenheit.

Water-Heating Fuel: The fuel used to heat water for washing or bathing. The hot water may be available anywhere in the same building as the respondent's living quarters--in a hallway, in a room used by several units in the building, in the basement, or in an enclosed porch--provided the household has access to it.

Watt (w): The unit of electrical power equal to 1 ampere (amp) under a pressure of 1 volt. Equal to 1/746 horsepower.

Watthour (Wh): An electrical energy unit of measure equal to 1 watt of power supplied to, or taken from, an electric circuit steadily for 1 hour.

Weight: The number of households in the United States that a particular sample unit represents. The estimate of the number of households with a certain characteristic (such as use of electricity as the main space-heating fuel) equals the sum of the weights over the set of households with the characteristics. (See Multistage Area Probability Sample and Appendix B, "Survey Estimates and Data Quality.")

Well Pump: See Electric Pump for Well Water.

Windows: Openings in the building envelope that contain framed glass. Windows in unheated spaces such as a garage or unheated basement are not counted. Generally, each window that opens separately is counted as one window. Panes of glass in a large window are not counted separately unless they open separately. Double-hung slider windows count as one window. Windows (glass panels) in doors are not counted.

Wood: Products from trees including logs, scraps such as mill waste or bark, manufactured logs, and pellets burned for their heat or aesthetic value. (See Wood Pellets.)

Wood-Burning Stove: See Heating Stove Burning Wood, Coal, or Coke.

Wood Pellets: Sawdust compressed into uniform diameter pellets to be burned in a heating stove.

Year of Construction: The year the structure was originally completed or the year any part of the structure was first occupied. For mobile homes, year of construction is the model year.

Year-Round Unit: Housing unit occupied or intended for occupancy at any time during the year. (See Housing Unit and Seasonal Unit.)


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File Last Modified: August 17, 2004