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Insulation & Composite Foam Cores

Glossary of Terms F-N

A-E F-N O-Z

“F" RATING: A rating usually expressed in hours indicating a specific length of time that a fire-resistive barrier can withstand fire before being consumed or permits the passage of flame through an opening in the assembly.
Facing: A thin covering adhered to the surface of insulation prior to field installation.
Fan: A mechanical air-moving device.
FDA Approval: Compliance with the Food and Drug Administration's regulations for food handling operations.
Fiber Glass: See fibrous glass.
Fibrous Glass: A synthetic vitreous fiber insulation made by melting predominantly silica sand and other: inorganic materials, and then physically forming the melt into fibers. To form an insulation: product, there are often other materials applied to the mineral wool such as binders, oils, etc.Commonly referred to as either fiber glass or fiberglass.
Fibrous Insulation: Insulation composed of small diameter fibers that finely divide the air space. Fibers used are: silica, rock wool, slag wool or alumina silica.
Film (Wet): The applied layer of mastic or coating before curing or drying.
Finishes: Jackets, mastics or strong films used for aesthetics or to protect insulation from at least one or: more of the following: weather, mechanical, and/or personnel abuse.
Finishing Cement: A mixture of various insulating fibers, fillers and binders with water, with or without hydraulic: cement, to form a smooth trowelable paste insulation for smooth application over insulating: cement or unfinished block insulation.
Fire Resistance: The property of a material or assembly to withstand fire or give protection. It is characterized by: the ability to confine a fire and to continue to perform a given structural: function.
Fire Retardance (FR): The property of a material that retards the spread of fire.
Firestopping: Furnishing and installing a material or a combination of materials to form an effective barrier: against the spread of flame, smoke, gases and moisture. It is to maintain the integrity of the firerated: construction.
Fish-Mouth: A gap between layers of sheet materials caused by warping or bunching of one or both layers.
Fitting Cover: The insulation for a pipe fitting composed of the specified thickness of insulation material, which: may be preformed. Also, a preformed jacketing.
Fittings: Items used to change size, direction of flow, level or assembly of piping, except for unions,: grooved couplings, flanges, valves or strainers.
Fixture Connection: Final piping connections to plumbing fixtures (usually exposed and chrome-plated).
Flame Retardant: The quality of a material to limit the flame spread across its surface.
Flame Spread: The index rate expressed in distance and time at which a material will propagate flame on its: surface.
Flange Cover: The insulation for a pipe flange composed of the specified thickness of insulation material, may: be preformed. Also, a preformed jacketing.
Flange: A projecting collar attached to a pipe for the purpose of connecting to another pipe, valve or: fitting.
Flash Point: The temperature at which combustion is initiated.
Flashing: The arrangement of metal or other weather barrier: Flexibility: That property of a material that allows it to be bent (flexed) without loss of strength or integrity.
FLEXIBILITY: That property of a material which allows it to be bent (flexed) without loss of strength.
FLEXURAL MODULUS: Ratio of maximum fiber stress to maximum strain, within elastic limit of the stress-strain diagram obtained in the flexure test. The flexural modulus is a measure of elasticity, or the ability for the material to be deformed and return to its original shape. An alternate term is the Flexural Modulus of Elasticity.
FLEXURAL STRENGTH: The flexural strength of a material is its ability to resist deformation under load, or how much you can bend the material before it starts to break. For materials that do not break, the load at yield, typically measured at 5% deformation/strain of the outer surface, is reported as the flexural strength or flexural yield strength. The general term for bending stiffness is flexural rigidity, which is the product of the material's elastic modulus and the cross section moment of inertia.
Foamed Plastic: Plastic expanded to a cellular form by thermal or chemical means.
F-Rating: A rating usually expressed in hours indicating a specific length of time that a fire resistive barrier: can withstand fire before being consumed or permits the passage of flame through an opening in: the assembly, as determined by ASTM E 814 (UL 1479).
Freeze/Thaw Stability: The property of a product that allows it to be subjected to temperatures below freezing and still: be useable when returned to room temperature.
Fresh Air Duct (Make-Up Air): A duct used to convey outdoor air to a point within the building, terminating at the mixing: plenum, air handling unit or discharge grill.
FRESH AIR: Air taken from outdoors.
Fresh Air: Air taken from outdoors.
FRIABILITY: The characteristic of a material to lose mass as a result of a combination of abrasion and impact produced by a laboratory tumbling mechanism.shed particles. Insulation friability is of concern during handling and insulation, since insulation with higher friability can abrade unprotected hands and raise dust that can irritate lungs. Dyplast's polyisocyanurate and expanded polystyrene have excellent friability characteristics. Friability of preformed block-type thermal insulation is measured per ASTM C421.
FSK: Foil scrim Kraft. This is a laminate composed of a thin layer of aluminum foil, glass fiber: reinforcing scrim, and Kraft paper.
Fuel Contribution: Combustible by-products from a substance generated or emitted in a burning: environment.
Galvanic Corrosion (Electrolysis): Effect of two dissimilar metals in the presence of an electrolyte to produce a weak voltaic cell: causing depleting or pitting of the more soluble metal.
Glass Cloth: Closed-weave glass fiber used as a finish jacket.
Glass Fabric: Open-weave glass fiber used as a reinforcing membrane.
Glass Fiber: An inorganic fiber manufactured as continuous filament from molten glass or silica, normally: used for reinforcement, tissue or textiles.
Glass Scrim: See glass fabric.
Gore: Curved segment of a finish jacket used for elbows, tank heads or other curved surfaces.
Granular Insulation: Insulation composed of small nodules that contain voids or hollow spaces. The material may be: calcium silicate, diatomaceous earth, expanded vermiculite, perlite, cellulose or microporous: insulations.
Graybody: A body having the same spectral emittance at all wavelengths.
Handicapped Fixtures: Exposed fixture connections located in facilities for the handicapped. Waste and hot piping: exposed connections in these areas are usually insulated for personnel protection.
Hanger (Pipe): Devices used to support piping.
Heat Flow, Heat Flow Rate: The quantity of heat transferred to or from a system in unit time.
Heat Flux Transducer (HFT): A device containing a thermopile (or equivalent) that produces an output that is a function of the: heat flux.
Heat Flux: The heat flow rate through a surface of unit area perpendicular to the direction of heat flow.
Heated Space: Building area supplied directly with heat.
Heel: The outside of an elbow.
Hertz (Hz): A measurement of sound frequency measured in cycles per second.
High Pressure Condensate: That condensate directly received from high-pressure steam lines.
High Pressure Steam: Steam at or above 75 pounds per square inch gauge pressure.
High Rib Lath: A metal lath with a built-in rib used to provide air space under insulation applications.
High Velocity Duct: A duct designed with air flow at more than 2,000 feet per minute velocity with a static pressure: exceeding 6 inches.
Homogeneous Material: A material in which relevant properties are not a function of the position within the material.
Horizontal Piping: Any piping up to and including 45° from the horizontal plane.
Housings (Built-Up): Assembled or fabricated at the construction site.
Housings (Casings): Enclosures of sheet metal or other material to house fans, coils, filters or other components of air: handling equipment.
Hubs: Caulking or cement connections between pipe joints.
Humidity, Absolute: The ratio of the mass off water vapor to total volume of an air sample. The I-P units are pounds: of moisture per pound of cubic foot of air and the SI units are grams or kilograms of moisture per: cubic meter of air.
Humidity, Ratio: The ratio of the mass of water vapor to the mass of dry air in an air sample. The I-P units are: either pounds of moisture per pound of dry air or grains of moisture per pound of dry air; the SI: units are grams of moisture per gram of dry air.
Humidity, Relative: One of the following ratios (a) the mole fraction of water vapor in a given moist air sample to the: mole fraction in the air sample saturated at the same temperature and pressure; (b) the vapor: pressure in a given moist air sample to the vapor pressure in the air sample saturated at the same: temperature and pressure and (c) the humidity ratio in a given moist air sample to the humidity: ratio in the air sample saturated at the same temperature and pressure. There are no units.
Humidity: A measure of the amount of water vapor in the ambient air.
HYGROSCOPICITY: Tendency of a material to absorb water vapor from the air. Especially pertinent for materials whose physical characteristics are altered by effects of water vapor.
IARC: International Agency for Research on Cancer
ICBO: International Council of Building Code Officials.
ICC: International Code Council.
Impact Resistance: Capability of an insulation material and/or finish to withstand mechanical or physical abuse.
Impale: To pierce or fix by piercing on a sharp point or pin.
Insulate: To cover with a material of low thermal conductivity in order to reduce the passage or leakage: of heat.
Insulating Cement: A mixture of various insulating fibers and binders with water to form a moldable paste insulation: for application to fittings, irregular surfaces or voids.
Insulation Hanger: A device such as a welded pin, stud or adhesive secured fastener that carries the weight of: insulation.
Insulation: Those materials or combination of materials that retard the flow of heat.
Intumescent: A characteristic of certain firestop products that when exposed to heat, expand to seal and fill: any void in the penetration. When exposed to fire, intumescent products will form a hard char.
ISOCYANATE: A compound containing the isocyanate group, -N=C=O, attached to an organic radical or hydrogen.
Jacket (as Related to Insulation Jacketing): A protective covering installed over thermal insulation.
Joint: The place where two adjacent pieces of material or jacketing meet. They may be overlapped,: sealed, filled (pointed) or finished by the application of tape, cement, mastic, coatings, additional: layer of insulation materials or other compounds.
k-Value (Thermal Conductivity): See Conductivity, thermal.
Lacing: A method of joining or securing insulation materials, reinforcements, or finishes for: insulation materials using eyelets, hooks, wire, cord, etc.
Lag: (v.) To apply lagging. (n.) A single piece of covering material.
Lagging Adhesive: Water based resin emulsion products that are used to adhere lagging cloth to the insulation and to: itself at the lap joints. They also seal and size the fabric and shrink it tightly to the surface. They: can be brushed or sprayed.
Lagging—Insulation: Definition 1: A block material for insulating tanks and boilers, usually curved or tapered and can: be made from any of several insulation materials. Definition 2: Insulation used on pipe, tanks, ducts, vessels, or other mechanical equipment. Discussion - lagging-insulation is usually applied in the form of cut, pieced together or mitered: parts.
Lagging—Jacketing: Jacketing installed over insulation. Also see “Jacket.”: Laminate: A product made by bonding together two or more layers of material or materials.
LAMINATE (n.): A product made by bonding together two or more layers of material or materials.
Lap Adhesive: The adhesive used to seal the butt joints and laps of insulation jackets.
Lath—Expanded Metal: A lattice type of material of various gauges and sizes, used to provide reinforcement for: insulation materials. Also used as a facing for metal-mesh insulation.
Lath—High Rib: A metal lath with a built-in rib used to provide air space under insulation applications.
LISTING (UL): Underwriters Laboratories, the world’s largest, not-for-profit product safety testing and certification organization with global name recognition and acceptance. Founded in 1894 in the US, it permits the use of its listing mark (the UL mark) as its stamp of approval on goods and materials after standardized and stringent testing. Thereafter its inspectors regularly visit the producer to audit compliance with its certification requirements.
Log Mean (Radius): The equivalent value of insulation thickness for pipe (curved surfaces) to produce the same: resistance to heat flow as per flat areas.
Loose or Fill Insulation: Insulation consisting of loose granules, fibers, beads, flakes, etc., which must be contained and: are usually placed in cavities.
Loose-Fill Insulation: Insulation in granular, nodular, fibrous, powdery or similar form designed to be installed by: pouring, blowing or hand placement.
Low-Pressure Condensate: Condensate directly received from low-pressure steam.
Low-Pressure Steam: Steam at or below 15 pounds per square inch gauge.
Low-Velocity Duct: A duct designed with air flow at not more than 2,000 feet per minute velocity with static pressure: not above 2 inches.
Main: Piping or ductwork from a source to the last branch connection or from the last branch: connection returning to the source or to a termination point.
Mastic: A protective coating applied by spray or trowel to weatherproof or otherwise prevent: deterioration of the insulation to which it is applied.
Mat: A piece of insulation of the semi-flexible type, composed of fibers of one or more kinds in which: the fibers are in random arrangement, used to support another material.
MDI: An abbreviation for 4,4’ diphenylmethane diisocyanate.
Mean Specific Heat: The quantity of heat required to change the temperature of a unit mass of a substance one degree,: measured as the average quantity over the temperature range specified. (It is distinguished from: true specific heat by being an average rather than a point value).
Mean Temperature: Sum of the cold surface temperature and the hot surface temperature divided by two. (Thermal: conductivity charts are calculated to use mean temperatures).
Mechanical Couplings: Bolting devices used in assembly of piping.
Medium Pressure Condensate: Condensate directly received from medium-pressure steam.
Medium Pressure Steam: Steam under 75 pounds per square inch gauge, but above 15 pounds psig.
Medium Velocity Duct: A duct designed with airflow over 2000 feet per minute velocity with a static pressure below 6: inches.
Membrane Reinforcement: Woven or non-woven fabrics used for saturation and embedment in mastic and coating: applications to provide strength, continuity and impact resistance. See glass fabric.
Metal Lagging: See jacket.
METRIC PERM: Perm measured at 23C Kilogram per Pascal Second square meter [kg/Pa-s-m2]
Microporous Insulation: Material in the form of compacted powder with an average interconnecting pore size comparable: to or below the mean free path of air molecules at standard atmospheric temperature and: pressure. Microporous insulation may contain fibers to add integral strength and opacifiers to: reduce the amount of radiant heat transmitted.
Mineral Fiber: Insulation composed principally of fibers manufactured from rock, slag, or glass, with or without binders.
Mineral Wool: A synthetic vitreous fiber insulation made by melting predominantly igneous rock, and or: furnace slag, and other inorganic materials, and then physically forming the melt into fibers. To: form an insulation product, there are often other materials applied to the mineral wool such as: binders, oils, etc.
Mixed Air Duct (Plenum): A duct or plenum located at a point where air returned from a space inside the building, and fresh: air are mixed or metered by dampers for redistribution through the air handling unit.
Moisture Barrier (as related to Insulation Jacketing): A polymeric film or coating applied to the inner surface of metal jacketing for the primary: purpose of reducing electrolytic, pitting, or crevice corrosion of the jacketing: Discussion – moisture barriers are not water vapor barriers or water vapor retarders
Moisture Retarder (as related to Insulation Jacketing): See Moisture Barrier (as related to insulation jacketing): Mold and Mildew Resistance: The property of a material that enables it to resist the formation of fungus growth.
MOLD AND MILDEW RESISTANCE: That property of a material which enables it to resist the formation of fungus growth.
NFPA: National Fire Protection Association.
Noise Reduction Coefficient (NRC): A single number rating that is the arithmetic average of the individual sound absorption: coefficients at 250, 500, 1000 and 2000 Hz to the nearest 0.05.
Noncombustible: A material that will not contribute fuel or heat to support a fire to which it is exposed.
Nonflammable: A material that will release very little heat when exposed to fire or flame.