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Carpet Glossary H


Animal fiber other than wool or silk


The extension of fibers above the normal level of the use surface or pile or textile fabrics. Hairiness usually is not removed by brushing or vacuuming.


Any of the five elements of chlorine bromine, iodine, fluorine, and astatine that have strong disinfecting properties.


The tactile esthetic qualities of carpets and textiles. Factors determining how carpets feel to the hand include weigh, stiffness, fiber type and denier, density, backing, and latex.

hand protection

Reference to specific types of gloves or other hand protection required to prevent harmful exposure to hazardous materials, or physical hazards.

hang pick

A pick that is caught on a warp yarn knot for a short distance which produces a triangular hole in the fabric. Hang picks usually result from knots that are tied incorrectly,shuttle tension that is too loose, or harness that is timed too early.


1. A skein of yarn. 2. A standard length of slubbing, roving, or yarn. The length is specified by the yarn numbering system in use. 3. A term applied to slubbing or roving that indicates the yarn number.

hard size

A condition found in areas of a fabric where the warp containing an excessive quantity of sizing.

hard water

Water that contains certain salts, such as those of calcium or magnesium, which form insoluble deposits in boilers and from precipitates with soap.


1. When used in reference to water, hardness is the total parts per million (ppm) of calcium as CaC0 plus the magnesium expressed as equivalent hardness. 2. Used in reference to pulpto denote the degrees of delignification. 3. That property of a dried film of finishing material that causes it to withstand denting or being marked when pressure is exerted on its surface by an outside object or force.


1. The frame holding the heddles through which the warp ends are drawn and then raised and lowered to form the shed. 2. Part of a weaving loom comprising the frames holding the heddles through which the warp yarns pass and used to raise and lower them to form the shed in which the shuttle moves to insert fill yarn.

hazard class (DOT)

The Department of Transportation (DOT) requires that hazardous materials offered for shipment be labeled with the proper DOT hazard class. These classes include: corrosive, flammable liquid, organic peroxide, ORM-E, poison, etc. The DOT hazard class may not adequately describe all the hazardous properties of the material.

hazard rating (hr)

A rating assigned to a material on a scale from 1-3 that briefly identifies its level of toxicity as follows: 1. Indicates an LD 50 below 400 mg/kg 2. Indicates and LD 50 of 400 - 4000 mg/kg 3. Indicates an LD 50 of 4,000 - 40,000 mg/kg.

hazardous decomposition products

Any hazardous materials that may be produced in dangerous quantities if the material reacts with other agents, burn, or is exposed to other processes such as welding.

hazardous ingredients

The hazardous substances that make up a mixture or compound.

hazardous material

A chemical in sufficient quantity or concentration to pose a threat to health or property; or which can cause injury due to its nature, or its properties.

hazardous polymerization

Polymerization is a chemical reaction in which one or more small molecules combine to form larger molecules. A hazardous polymerization is a reaction that takes place at such a rapid rate that large amounts of energy are released. If hazardous polymerization can occur with a given material, the MSDSusually will list conditions that could start the reaction, and since the material usually contains a polymerization inhibitor, the expected time before the inhibitor is used up.

hazardous waste

Waste which causes harm upon contact. Hazardous waste is a toxic and carcinogenic waste and can pose a substantial or potential hazard to human health or the environment when improperly managed…

health hazard

A chemical for which there is statistically significant evidence, based on at least one study conducted in accordance with established scientific principles, that acute or chronic health effects may occur when worker are exposed. The term health hazard includes chemicals that are carcinogens, toxic or highly toxic agents.

heat bonded

Type of construction where the face fibers are bonded to the surface of the backing material rather than tufted or woven into the backing.

heat embossed

Method for melting a pattern into the surface.

heat gun

An electrically operating, heavy duty combination heater and forced air blower that is used to soften materials when cutting, shaping, and coving resilient sheet goods, or for force drying adhesives.

heat resistance

A property of certain fibers or yarns whereby they resist degradation at high temperature. Heat resistance may be an inherent property of the fiber forming polymer or it may be imparted by additives or treatment during manufacture.

heat set

1. Stabilization of yarns to insure no change in size or shape. 2. Process for stabilization of carpet yarns by exposure to heat. Conventional autoclave heat setting treats yarns in relaxed skein configuration with pressurized steam.

heat set nylon

Nylon, a thermosetting resin, can be cross linked by heat to form a three dimensional matrix that holds its shape.

heat setting

Process for stabilization of carpet yarns by exposure to heat. Conventional autoclave heat-setting treats yarns in relaxed skein configuration with pressurized steam, usually at temperatures in the 240o F -300o F range, often 270o F for nylon. Some continuous heat-setting machines employ dry heat. The principal benefits are twist retention in plied yarns in cut-pile carpet and general stabilization of yarn configuration.

heat stabilized

A term to describe fiber or yarn heat treated to reduce the tendency of the fiber to shrink or elongate under load at elevated temperatures.


A multicolor effect provided by blending fibers of different colors prior to spinning carpet yarn.

heavy denier

Refers to heavy denier per filament fibers (that is, heavier individual filaments) making up fewer total filaments in a yarn bundle. Heavy denier yarns are better soil releasing yarns and clean easier.

heavy filling

See coarse thread.

heavy metals

Metallic elements with high atomic weights, such as mercury, chromium, cadmium, arsenic, and lead. They can damage living organisms at low concentrations.

heavy pick

See coarse thread.

heavy traffic

A term used to describe commercial environments where directional, non-directional, some rolling traffic, tracked in dirt, and spills occur at a consistently high level. Heavy traffic is greater than 800,000 walk-ons, up to 2,000,000 total traffics, for the life of the carpet.


A series of vertical cords or wires, each of which has in the middle a lope or eye which receives a warp yarn. The two heddle frames, each carrying a set of chain warp yarns, rise and fall alternately forming the shed through which the weft shuttle passes.

heddle frame

The frame on which the heddles are mounted.

hedonic tone

The degree to which an odor is perceived as pleasant or unpleasant. Expressed in terms of preference, such as dislike very much, like slightly, or even facial expressions of smiling or frowning.


A technique of applying pressure to the side or rear of a floor machine to remove black shoe marks or persistent soil. Heeling and toeing a shampoo machine during carpet cleaning can result in non-uniform cleaning as well as pile distortion streaks across the direction of cleaning.


A coarse, durable bast fiber of Cannabis sativa found all over the world. Used primarily for twines, cordage , halyards, and tarred riggings.

HEPA - High Efficiency Particle Arrestor

Designates air filtration bags or filters that remove 99.97% of all particles down to 0.3 microns in size.

hermetically sealed building

A sealed building that has few air leaks so that no outside air can enter. The only air supply comes through the HVAC system.


Plain woven jute fabric with approximately equal numbers of warp and fill yarns per unit dimension


One of the synthetic phenol compounds currently used in prescription antiseptic soaps.


A petrochemical compound with a chain of six carbon atoms, which is reacted with adipic acid to make type 6,6 nylon.

hexapod drum

A twelve (12) inch diameter rotating drum into which carpet samples are placed, and then subjected to simulated trafficking with a metal ball with six attached polyurethane cleats or studs.

high bulk yarn

See textured yarn.

high density

A term for materials or structures having above average weight per unit volume.

high density foam

1. Attached carpet cushion (carpet padding) made from compounded natural and/or synthetic latex foam having a minimum density of 17 pounds per cubic foot and a minimum weight of 38 ounces per square yard. 2. Rubber product applied as a liquid foam and cured to form an integral part of the carpet back. Weights vary from 38 oz. to 45 oz. per square yard.

high low

Multilevel carpet style combining high-loop and low-loop pile areas or high-cut pile and low-loop areas. The latter is also called a cut and loop style.

high low lines

High and low lines running lengthwise in carpet that are normally associated with a “J” cut. One row of tufts will have a high leg and the parallel row will be low, or perhaps even nonexistent. In some cases the high leg will be sheared down to the level of the pile in general, leaving only a low line. Low lines also may be caused by improper tension on yarns when fed into the tufting machine.

high low pile

A pile construction characterized by the presence of two or more pile heights, sometimes combining looped or cut surface yarns.

high pH finish

A finish, basic in nature rather than acid or neutral, that is applied to yarn or fiber.

high shrink staple

Staple with a higher degree of potential shrinkage than regular staple of the same generic fiber. When blended with regular staple and treated to induce shrinkage, it produces a high degree of bulk in the product.

high temperature dyeing

A dyeing operation in which the aqueous dyebaths are maintained at temperatures greater than 100 degrees C by use of pressurized equipment. used for many manufactured fibers.

high tenacity

A term used to describe a material with a higher than normal tensil strength.

hollow filament fiber

A fiber with chemically or mechanically engineered interior voids that provide soil hiding characteristics through the diffusion of light. Hollow filament fibers should be at least 89% solid polymer so that the interior voids do not weaken the fiber and cause it to fray under heavy wear.

hooked rugs

Yarn or strips of cloth inserted into a prewoven cloth stenciled with a pattern.

hooks/wire hooks

1. The vertical wires in a Jacquard that are hooked on each end and the bottom hook attached by cords to the lingo heedles carrying the pattern yarn. The top hooks are positioned by the needles to either to be caught onto or clear the lifting knife in the griff. In most Jacquards, the hooks that are picked by the lifting knives raise a face yarn end over the filling shot and/or wire. 2. The hook shaped stamped metal latches used to catch the pile wire after it is beaten up an retard the wire’s tendency to jump or fall toward the reed.


The assembly that engages the pile wire head, drawing it from the front of the wire set returning it under the pile shed.


An organic material that harbors and provides nourishment for saprophytic or parasitic micro-organism.


A dry absorbent cleaning compound (cellulose based) produced by Racine Industries.

hot melt

1. A blend of polymer and filling applied in a heated state to carpet back, to lock in surface yarns and for lamination. 2. Adhesive material sometimes used for laminating secondary backing to tufted carpet; also used as the adhesive component of carpet seaming tape. Hot melt adhesives are compounded from thermoplastic polymers and plastics. They may be melted and solidified repeatedly by application of heat.

hot melt adhesive

A solid material that melts quickly upon heating, then sets to a firm bond upon cooling. Use of this type adhesive provides almost instantaneous bonding.

hot melt backing

A heavy backing made of a blend of polymer and filler which is applied to the back of a carpet in a melted state.

hot water extraction

A restorative method of carpet cleaning that begins with dry soil removal (vacuuming) and preconditioning (detergent application to heavily soiled areas with agitation for even distribution, and dwell time. Hot water, from a holding tank made into the cleaning unit (often combined with detergent) is injected under pressure. Suspended soil is removed from carpet or fabrics through a combination of the flushing action of injected solutions, coupled with wet vacuuming. Excess solution and suspended soil is collected within a recovery tank.


A chemical which attracts and hold available moisture from the ambient air.


The measure of moisture in the atmosphere. From an air quality standpoint, humidity in a built environment should be maintained between 30% - 50%, according to the Consumer Product Safety Commission. Excessive humidity is above 60% rh, with humidity above 70% creating an atmosphere that’s highly conducive to rapid micro-organisms growth.

HVAC system

Heating, ventilation, Air-Conditioning system.


Energy (pressure) exerted by or transmitted through fluids in motion.

hydrocarbons (HC)

Chemical compounds that consist entirely of carbon and hydrogen.

hydrogen peroxide

An antiseptic, and an oxidizing bleach used in a three percent (3%) solution for spotting and browning correction.


The process of passing hydrogen into an unsaturated chemical in the presence of a catalyst to convert the material to a more saturated state.


A double decomposition reaction involving the addition of the elements of water and the formation of an acid and a base, an acid and an alcohol, or an acid and phenol. A chemical decomposition involving splitting a bond and adding element of water.


Water loving. A term applied to that portion of a detergent molecule that an affinity for water.


Water fearing. A term applied to that portion of a detergent molecule that has an affinity for non-water surfaces or substances. The hydrophilic and hydrophobic portions of the detergent molecule have a direct and extremely important role to play in detergent function, such as defluculation, emulsification, suspension, etc. lacking the ability to absorb water.


Having the ability to absorb moisture from the atmosphere. All fibers have this property in varying degrees.


Relating to pressure exerted by fluids.


A scientific instrument used to automatically record and plot changes in relative humidity in an environment.


Any of a variety of instruments used for measuring the humidity in air.


A material that readily absorbs and retains moisture or water vapor.


An instrument used to automatically record and plot changes in humidity and temperature.


An elongated, cylindrical, rod shaped structure forming the basic fungus structure.


The active bleaching and disinfecting ingredient in liquid chlorine bleach.

Did you know?

42% of all carpet cleaning is performed by do it yourself carpet cleaning methods. Do it yourself carpet cleaning is easy and can reduce carpet wear. Proper carpet care using proper carpet cleaning procedures, while do it yourself cleaning will extend carpet life.