Building Utilities (Mechanical) Flashcards
A measure of the warmth or coldness of a substance, object, or environment with reference to some standard value.
Temperature
An instrument for measuring temperature, consisting typically of a glass tube with a numbered scale and bulb containing a liquid, such as mercury, that rises and falls with changes in temperature.
Thermometer
The quantity of heat required to raise the temperature of one pound (0.4kg) or water 1 degree F.
British thermal unit
A unit of heat equal to 100,000 British thermal unit.
Therm
A unit of heat equal to the quantity of heat required to raise the temperature of one gram of water 1 degree C at a pressure of one atmosphere, equivalent to 4.186 joules.
Calorie
A unit of heat equal to the quantity of heat required to raise the temperature of one kilogram of water 1 degree C at a pressure of one atmosphere, equivalent to 1000 small calories.
Kilocalorie
A temperature scale in which 32°F represents the freezing point and 212°F the boiling point of water under standard atmospheric pressure.
Fahrenheit scale
A temperature scale divided into 100 degrees, in which 0°C represents the freezing point and 100°C the boiling of water under standard atmospheric pressure.
Celsius scale
An absolute scale of temperature having a zero point of - 273.16°C.
Kelvin scale
A temperature scale based on absolute zero with scale units equal in magnitude to centigrade degrees.
Absolute scale
The hypothetical lowest limit of physical temperature characterized by complete absence of heat, equal to -273.16° C or -459.67°F.
Absolute zero
Temperature as measured on an absolute scale.
Absolute temperature
The base SI unit of temperature equal to 1/273.16 of the triple point of water.
Kelvin
The particular temperature and pressure at which the liquid, gaseous, and solid phases of a substance can exist in equilibrium.
Triple point
The transfer of heat by the circulatory motion of the heated parts of a liquid or gas owing to a variation in density and the action of gravity.
Convection
The transfer of heat from the warmer to the cooler particles of a medium or of two bodies in direct contact, occurring without perceptible displacement of the particles themselves.
Conduction
The process in which energy in the form of waves or particles is emitted by one body, passed through an intervening medium or space, and absorbed by another body.
Radiation
The time rate of heat flow through a unit area of a given material of unit thickness when the temperature difference across the thickness is one unit of temperature.
Thermal conductivity
The time rate of heat flow through a unit area of a given material when the temperature difference across a specified thickness of the material is one unit of temperature.
Thermal conductance
An element of low thermal conductivity placed in an assembly to reduce the flow of heat between highly conductive materials.
Thermal break
The reciprocal of thermal conductance expressed as the temperature difference required to cause heat to flow through a unit area of a material of given thickness at the rate of one heat unit per unit time.
Thermal resistance
A measure of thermal resistance of a given material, used esp. to specify the performance of thermal insulation.
R-value
The time rate of heat flow through a unit area of a building component or assembly when the difference between the air temperature on the two sides of the component or assembly is one unit of temperature.
Thermal transmittance
A measure of the thermal transmittance of a building component or assembly, equal to the reciprocal of the total R-value of the component or assembly.
U-value
The flow of outside air into an interior space through cracks around windows and doors or other openings in the envelope of a building.
Infiltration
A strip of metal, felt, vinyl, or foam rubber, placed between a door or window sash and its frame to provide a seal against windblown rain and air infiltration.
Weather strip
Any of various lightweight, inorganic, fibrous materials used esp. for thermal and sound insulation, such as glass wool and rock wool.
Mineral wool
Spun glass fibers resembling wool and used for thermal insulation and air filters.
glass wool
A material consisting of extremely fine filaments of glass, woven into fabric, massed for use as a thermal and acoustical insulator, or embedded to reinforce various materials.
Fiberglass
Trademark for a brand of fiberglas
Fiberglas
Mineral wool made by blowing steam or air through molten slag or rock.
Rock wool
Plastic, such as polyurethane or polystyrene, made light and cellular by the introduction of pockets of gas or air and used as thermal insulation.
Foamed plastic
A rigid expanded polyurethane having a closed-cell structure and used as thermal insulation.
Polyurethane foam
A rigid polystyrene foam having an open-cell structure and used as thermal insulation.
Molded polystyrene
A rigid polystyrene foam having a closed-cell structure and used as thermal insulation.
extruded polystyrene
Trademark for a brand of formed plastic made from polystyrene.
Styrofoam
Cellular glass made by forming softened glass and molding it into boards or blocks for use as thermal insulation.
Foam glass
Fine wood shavings, usually of pine or chemically treated wood fibers, used as an insulating material, as a binder in plaster, and for packing.
Wood wool
The passageway required for the circulation of air between batt insulation and roof sheathing.
Airway
Flexible, fibrous thermal insulation of glass or mineral wool, made in various thicknesses and lengths and 16-in (400mm) or 24 in. (610mm) widths to fits between studs, joist, sometimes faced with a vapor retarder of kraft paper, metal foil, or plastic sheet.
Batt insulation
A strong, usually brown paper, processed from wood pulp and sized with resin.
Kraft paper
A preformed, nonstructural insulating board of foamed plastic or cellular glass. Cellular glass insulation is fire-resistant, impervious to moisture, and dimensionally stable, but has a lower thermal-resistance value than foamed plastic insulations, which are flammable and must be protected by a thermal barrier when used on the interior surfaces of a building.
Rigid board insulation
Thermal insulation in the form of a foamed plastic, such as polyurethane, that is sprayed or injected into a cavity where it adheres to the surrounding surfaces.
Foamed-in-place insulation
Thermal insulation in the form of mineral wool fibers, granular vermiculite or perlite, or treated cellulosic fibers, poured by hand or blown through a nozzle into a cavity or over a supporting membrane.
Loose-fill insulation
Thermal insulation in the form of a material of high reflectivity and low emissivity, such as paper-backed aluminum foil-backed gypsum board, used in conjunction with a dead-air space to reduce the transfer of heat by radiation.
Reflective insulation
An unventilated air space in which the air does not circulate.
Dead-air space
A material providing high resistance to heat flow, such as mineral wool, vermiculite, or foamed plastic, fabricated in the form of batts, blankets, boards or loose fill.
Thermal insulation
To make a house or building secure against cold or stormy weather, as by adding thermal insulation or storm windows, or by sealing joints.
Weatherize
An insulating board made of wood or cane fibers compressed and cemented into rigid sheets, used as an inexpensive wall finish or as ceiling tiles.
Fiberboard
Insulating fiberboard treated or impregnated with asphalt for water resistance and used primarily for sheathing light wood frame walls.
Fiberboard sheathing
The ability of a surface to emit heat by radiation, equal to the ratio of the radiant energy emitted to that emitted by a black body at the same temperature.
Emissivity
Human comfort as determined by the ability of the body to dissipate the heat and moisture it produces by metabolic action.
Thermal comfort