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UPMSP Vocational Laundry & Dyeing study materials
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UPMSP Vocational Laundry & Dyeing practice questions

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Question 1Fundamentals of Laundry and Dyeing

In the laundering process, what is the main purpose of adding detergent to the wash liquor?

  1. To raise the pH of the fabric to a neutral level
  2. To lower the surface tension of water so soils can be lifted and suspended Correct answer.
  3. To increase the hardness of water so minerals bind the soil
  4. To coat the fibres with a protective wax layer

Explanation

Detergents are surfactants: they reduce the surface tension of water, allowing the liquor to wet fibres and lift oily and particulate soil into suspension so it can be rinsed away. They also help keep removed soil from redepositing. Raising water hardness or coating fibres with wax would work against cleaning.

Question 2Fundamentals of Laundry and Dyeing

Which water is described as 'hard' in laundry practice?

  1. Water that lathers readily with soap
  2. Water that contains dissolved calcium and magnesium salts Correct answer.
  3. Water that has been softened by boiling only
  4. Water that contains no dissolved minerals at all

Explanation

Hardness is caused mainly by dissolved calcium and magnesium salts, which react with soap to form an insoluble scum and reduce detergent efficiency. Soft water lathers easily and contains few of these ions. Boiling removes only temporary hardness, so it does not define hardness itself.

Question 3Fundamentals of Laundry and Dyeing

Which fibre is a natural protein fibre that is damaged by strong alkalis and by chlorine bleach?

  1. Cotton
  2. Polyester
  3. Viscose rayon
  4. Wool Correct answer.

Explanation

Wool is a protein (keratin) fibre; strong alkalis and chlorine bleach attack the peptide bonds, causing yellowing, loss of strength and felting shrinkage. Cotton and viscose are cellulose fibres that tolerate alkalis well. Polyester is a synthetic fibre with good resistance to chlorine.

Question 4Fundamentals of Laundry and Dyeing

What does the term 'bleeding' mean when it occurs during a wash?

  1. Formation of lime scum on the drum
  2. Deposition of lint on dark garments
  3. Dye dissolving out of a coloured fabric into the wash liquor Correct answer.
  4. Shrinkage of the fabric along the warp direction

Explanation

Bleeding is the loss of dye from a coloured article into the wash liquor, where it may redeposit on lighter fabrics. It is caused by poor dye fastness, high temperature or excessive time in the bath. Shrinkage, lint and scum are separate defects with different causes.

Question 5Fundamentals of Laundry and Dyeing

Which natural dye source is traditionally used to give a blue colour on cellulosic fabrics?

  1. Pomegranate rind
  2. Turmeric rhizome
  3. Madder root
  4. Indigo leaf Correct answer.

Explanation

Indigo, obtained from Indigofera leaves, is the classic natural vat dye giving blue shades, especially on cotton. Madder gives reds, turmeric gives yellow, and pomegranate rind gives yellow-brown shades. Each source therefore produces a distinct hue.

Question 6Fundamentals of Laundry and Dyeing

Which laundry process is carried out to remove the sizing and starch applied to new fabric before it is dyed or finished?

  1. Scouring
  2. Mercerising
  3. Calendering
  4. Desizing Correct answer.

Explanation

Desizing is the specific step that removes added size (starch or synthetic sizing) from grey fabric so that subsequent wet processes can penetrate evenly. Scouring removes natural oils and waxes rather than added size. Mercerising and calendering are finishing treatments.

Question 7Fundamentals of Laundry and Dyeing

A laundry receives a batch of white cotton shirts with heavy collar soiling. Which sequence best follows good laundry practice?

  1. Wash with a large excess of detergent and skip the rinse stage
  2. Soak in cold water, then wash with bleach only, then tumble dry at high heat
  3. Wash in very hot water with no detergent to save cost
  4. Pre-treat the collars with a detergent paste, wash at the recommended temperature, then rinse thoroughly Correct answer.

Explanation

Pre-treating localised soil with a concentrated detergent paste loosens the soil before the main wash, and a proper rinse removes loosened soil and chemical residue. Washing without detergent or skipping rinsing leaves soil and chemicals on the fabric. Bleach alone does not remove oily collar soil effectively.

Question 8Fundamentals of Laundry and Dyeing

A customer brings a woollen sweater that must be cleaned without felting or shrinkage. Which method is most appropriate?

  1. Machine wash in hot water with a strong alkaline detergent
  2. Hand wash in cool water with a neutral detergent and dry flat Correct answer.
  3. Chlorine bleach treatment followed by tumble drying
  4. Boil the garment with soap to remove all soil

Explanation

Wool felts and shrinks when subjected to heat, alkali and mechanical agitation, so cool water, a neutral detergent and gentle handling are required. Drying flat prevents stretching under the garment's own weight. Hot water, strong alkali or chlorine bleach would damage the protein fibre.

Question 9Fundamentals of Laundry and Dyeing

A cotton fabric is dyed with a direct dye, but the shade is too pale and much dye remains in the bath. Which addition is most likely to improve dye exhaustion onto cotton?

  1. Adding a cationic softener before dyeing
  2. Adding common salt (electrolyte) to the dyebath Correct answer.
  3. Adding a reducing agent to the dyebath
  4. Lowering the dyebath temperature to near freezing

Explanation

Direct dyes are anionic and have only moderate substantivity for cellulose, so adding electrolyte such as common salt shields the negative charges and promotes migration of dye onto the fibre, improving exhaustion. A reducing agent would destroy the azo structure of many direct dyes, and cold water slows dye uptake.

Question 10Fundamentals of Laundry and Dyeing

Which class of dye requires a mordant such as alum to fix the colour to the fibre?

  1. Vat dye
  2. Disperse dye
  3. Mordant (chrome) dye Correct answer.
  4. Reactive dye

Explanation

Mordant dyes, also called chrome dyes, need a metal salt mordant that forms a complex linking dye to fibre and improves fastness. Reactive dyes form covalent bonds directly, disperse dyes physically dissolve into synthetic fibres, and vat dyes are fixed by oxidation after reduction.

Question 11Fundamentals of Laundry and Dyeing

What is the purpose of the 'soaping' step after dyeing cotton with a reactive dye?

  1. To set the dye by forming a covalent bond
  2. To increase the depth of shade by adding more dye
  3. To make the fabric more absorbent by removing sizing
  4. To remove unfixed hydrolysed dye and improve wash fastness Correct answer.

Explanation

After reactive dyeing, some dye has hydrolysed and is only loosely held on the fibre; soaping removes this unfixed dye so it cannot bleed later, improving wash fastness and shade clarity. The covalent bond has already formed during the fixation stage, so soaping does not set the dye.

Question 12Fundamentals of Laundry and Dyeing

A housekeeping supervisor wants to reduce water and energy use in the hotel laundry without compromising hygiene. Which measure is most effective?

  1. Use a tunnel washer with counter-flow rinsing and recover heat from effluent Correct answer.
  2. Extend the wash cycle time by 50 percent for all loads
  3. Add extra detergent to every load to shorten the cycle
  4. Increase the rinse-water temperature to near boiling

Explanation

Counter-flow washing in a tunnel washer uses the cleanest water for the final rinse and reuses it upstream, cutting water consumption, while heat recovery from hot effluent reduces energy demand. Simply raising temperatures or adding detergent increases resource use. Longer cycles also consume more energy.

Question 13Fundamentals of Laundry and Dyeing

Which chemical action describes the role of sodium hydrosulphite in vat dyeing?

  1. It reduces the insoluble vat dye to a soluble leuco form Correct answer.
  2. It neutralises alkali to lower the dyebath pH
  3. It oxidises the leuco form back to the insoluble pigment
  4. It acts as a levelling agent to slow dye uptake

Explanation

Vat dyes are insoluble pigments that must be reduced to their soluble leuco (vat) form before they can penetrate the fibre; sodium hydrosulphite is the reducing agent that performs this step in an alkaline bath. After penetration, air or an oxidising agent converts the leuco form back to the insoluble pigment inside the fibre.

Question 14Fundamentals of Laundry and Dyeing

A white polyester-cotton shirt shows a grey, dingy appearance after repeated washing with a poorly soluble detergent at low temperature. What is the most likely cause?

  1. Dye bleeding from the polyester component
  2. Chlorine bleaching of the polyester component
  3. Fabric shrinkage from the cotton component
  4. Detergent residue and redeposited soil on the fibre surface Correct answer.

Explanation

Detergent that does not fully dissolve at low temperature can leave a film on the fibre, and soil removed from the load may redeposit on it, giving a grey dingy look. The remedy is adequate temperature for dissolution, correct dosage and good rinsing. Bleeding, shrinkage and bleaching would produce different visible effects.

Question 15Fundamentals of Laundry and Dyeing

Which statement correctly distinguishes 'stain removal' from 'general washing' in laundry practice?

  1. Stain removal requires boiling the whole garment in every case
  2. Stain removal is performed only after the garment has been tumble dried
  3. Stain removal targets a localised area with a specific reagent before the main wash Correct answer.
  4. Stain removal uses the same detergent and temperature as the main wash

Explanation

Stain removal is a targeted pre-treatment: a reagent chosen for the specific stain type is applied to the localised area before the general wash. The main wash then removes overall soil. Treating after drying can set the stain permanently, and boiling is not appropriate for all fibres or stains.

Question 16Fundamentals of Laundry and Dyeing

Which factor most directly controls the shade depth obtained when dyeing a given weight of fabric with a given amount of dye?

  1. The speed of the squeezing mangle only
  2. The percentage dye on weight of fibre (owf) and the degree of exhaustion Correct answer.
  3. The colour of the dyebath container
  4. The length of the fabric piece

Explanation

Shade depth depends on how much dye is applied relative to fibre weight (expressed as percent owf) and on how much of that dye actually exhausts onto the fibre. Container colour and piece length do not determine dye uptake. Mangle expression affects wet pick-up and uniformity but is not the primary control of shade depth.

Question 17Fundamentals of Laundry and Dyeing

In a winch (beck) dyeing machine, which condition most favours level dyeing of a lightweight fabric?

  1. Rapid addition of all dye at the start followed by a short run
  2. A long liquor ratio with no agitation
  3. Gradual dye addition with controlled temperature rise and good liquor circulation Correct answer.
  4. Very high fabric speed with no temperature control

Explanation

Levelness depends on uniform contact between dye and fibre, so dye should be added gradually while temperature is raised slowly and liquor circulates well. Rapid addition or poor agitation causes uneven uptake and patchy shade. Excessive fabric speed can also cause rope marks and mechanical damage.

Question 18Fundamentals of Laundry and Dyeing

A dyer observes that a batch dyed with a reactive dye shows a lighter ring around the selvedges after washing. Which explanation is most consistent with this defect?

  1. Excess electrolyte evenly distributed throughout the bath
  2. Use of a dye with very high substantivity and slow addition
  3. Complete exhaustion of dye before fixation
  4. Uneven fixation caused by poor alkali penetration or uneven liquor flow at the selvedges Correct answer.

Explanation

Reactive dyes need alkali to fix; if alkali or liquor does not reach the selvedges evenly, less dye is fixed there and it washes out, leaving a lighter edge. Even electrolyte, complete exhaustion and slow addition of a high-substantivity dye all favour level, well-fixed results rather than this edge defect.

Question 19Fundamentals of Laundry and Dyeing

Why is hydrogen peroxide bleach normally applied to cotton in an alkaline bath containing a stabiliser?

  1. Alkali activates the peroxide and the stabiliser controls decomposition to prevent fibre damage Correct answer.
  2. Alkali stops the peroxide from bleaching and the stabiliser adds colour
  3. The stabiliser increases the bleaching temperature beyond boiling
  4. The alkaline bath is needed only to dissolve the cotton fibre

Explanation

Hydrogen peroxide bleaches most effectively under alkaline conditions, but uncontrolled decomposition of peroxide can attack cellulose and cause chemical damage (loss of strength, 'tendering'). A stabiliser such as sodium silicate keeps decomposition controlled so bleaching is even and safe.

Question 20Fundamentals of Laundry and Dyeing

A cotton fabric dyed with a direct dye is tested for wash fastness and shows significant colour loss and staining of an adjacent white strip. Which aftertreatment is most appropriate to improve fastness?

  1. Washing with a strong reducing agent
  2. Applying a non-ionic softener before dyeing
  3. Treating with a cationic dye-fixing agent after dyeing Correct answer.
  4. Raising the dyebath pH to strongly alkaline levels after dyeing

Explanation

Direct dyes have limited wet fastness because they are held mainly by hydrogen bonding and van der Waals forces. A cationic fixing agent forms a complex with the anionic dye on the fibre, reducing desorption during washing. Reducing agents destroy the dye, and strongly alkaline aftertreatment can promote desorption rather than fix it.

Question 21Textile Fibres and Fabric Identification

A fabric sample burns quickly with a smell of burning paper and leaves a soft grey ash. Which fibre is most likely present?

  1. Wool
  2. Nylon
  3. Polyester
  4. Cotton Correct answer.

Explanation

Cellulosic fibres such as cotton ignite readily, smell like burning paper and leave a soft grey ash that crumbles easily. This behaviour separates them from protein fibres, which smell of burnt hair, and from synthetic melts.

Question 22Textile Fibres and Fabric Identification

In the flame test, a yarn that smells of burning hair or feathers and leaves a brittle dark char most probably contains which fibre?

  1. Cotton
  2. Silk Correct answer.
  3. Acrylic
  4. Viscose rayon

Explanation

Silk is a protein fibre, so it behaves like wool in the flame: it burns slowly, smells of burnt hair and leaves a crushable dark char. The nitrogen in the protein structure causes that characteristic odour.

Question 23Textile Fibres and Fabric Identification

A yarn dissolves completely in cold dilute sodium hypochlorite solution. Which fibre does this confirm?

  1. Cotton
  2. Wool Correct answer.
  3. Glass fibre
  4. Polyester

Explanation

Wool is a protein fibre and is destroyed by chlorine bleach, which attacks the peptide bonds of keratin. Cellulosic and synthetic fibres resist cold dilute hypochlorite, so complete dissolution indicates an animal fibre.

Question 24Textile Fibres and Fabric Identification

A fabric gives a bright yellow stain when a drop of nitric acid is applied. This reaction indicates the presence of which fibre?

  1. Viscose rayon
  2. Polyester
  3. Cotton
  4. Silk Correct answer.

Explanation

Nitric acid produces a characteristic yellow colour on protein fibres such as silk and wool because of nitration of aromatic amino acid residues. Cellulosic and synthetic fibres do not give this yellow reaction.

Question 25Textile Fibres and Fabric Identification

When a single yarn is untwisted and examined, short fibres of varying length are seen twisted together. This structure is characteristic of which type of yarn?

  1. Filament yarn
  2. Monofilament yarn
  3. Staple yarn Correct answer.
  4. Tape yarn

Explanation

Staple yarns are made from short fibres of varying length that are twisted together to give strength. Filament yarns consist of long continuous strands, so untwisting them reveals long uniform filaments rather than short fibres.

Question 26Textile Fibres and Fabric Identification

A plain-weave fabric has 40 warp ends per inch and 30 weft picks per inch. Which statement about its thread count is correct?

  1. The total thread count is 1200 per square inch
  2. The total thread count is 30 per inch
  3. The total thread count is 40 per inch
  4. The total thread count is 70 per inch Correct answer.

Explanation

Thread count is the sum of warp ends and weft picks per inch, so 40 plus 30 gives 70 threads per inch. Counting only one direction describes ends or picks alone, not the total count.

Question 27Textile Fibres and Fabric Identification

On a woven fabric, a fine diagonal line runs from bottom left to top right. Which weave is this most likely to be?

  1. Twill weave Correct answer.
  2. Satin weave
  3. Plain weave
  4. Pile weave

Explanation

Twill weave produces a characteristic diagonal rib because the interlacing points shift by one or more threads in each successive pick. Plain weave gives a checkerboard surface and satin gives a smooth lustrous face without a diagonal line.

Question 28Textile Fibres and Fabric Identification

A fabric has a smooth, lustrous face and a dull back, with long floats of yarn crossing several threads. Which weave is described?

  1. Basket weave
  2. Twill weave
  3. Satin weave Correct answer.
  4. Plain weave

Explanation

Satin weave uses long floats that reflect light to give a lustrous face, while the reverse side is dull. The long floats also make the fabric prone to snagging compared with plain or twill weaves.

Question 29Textile Fibres and Fabric Identification

Which fabric is produced by a knitting process rather than by interlacing warp and weft threads?

  1. Canvas
  2. Denim
  3. Single jersey Correct answer.
  4. Poplin

Explanation

Single jersey is a weft-knitted fabric in which loops are intermeshed, giving stretch and a characteristic face-and-back difference. Poplin, denim and canvas are all woven by interlacing warp and weft.

Question 30Textile Fibres and Fabric Identification

A fabric curls strongly at the cut edges and shows fine vertical wales on the face. Which fabric type is this?

  1. Nonwoven felt
  2. Single jersey knit Correct answer.
  3. Warp-knitted tricot
  4. Woven poplin

Explanation

Single jersey weft knit has loops that tend to unroof at cut edges, causing curl, and its face shows fine vertical wales. Woven and nonwoven fabrics do not curl in this characteristic way.

Question 31Textile Fibres and Fabric Identification

A fabric sample is identified as a nonwoven. Which property best supports this identification?

  1. It is made of bonded or needle-punched fibres without yarn structure Correct answer.
  2. It has a clear warp and weft interlacing pattern
  3. It shows a regular diagonal twill line
  4. It has long floats on the face

Explanation

Nonwoven fabrics are made directly from fibres that are bonded, needled or fused without being spun into yarn and woven. The absence of yarn interlacing distinguishes them from woven and knitted structures.

Question 32Textile Fibres and Fabric Identification

A fabric is labelled as 100 percent polyester. Which combination of properties would you expect during identification?

  1. Thermoplastic behaviour, low moisture regain and melt dripping in flame Correct answer.
  2. Strong burnt-hair odour on burning
  3. High moisture regain and easy burning with paper smell
  4. Dissolves in cold hypochlorite solution

Explanation

Polyester is a thermoplastic synthetic with very low moisture regain, so it melts and drips when ignited and forms a hard bead. It does not burn like cellulose or smell like protein fibres.

Question 33Textile Fibres and Fabric Identification

A garment label claims the fabric is viscose rayon. Which identification result is consistent with this claim?

  1. It does not burn and is unaffected by acids
  2. It melts to a hard bead with a sweet smell
  3. It burns like paper and dissolves in cold concentrated sulphuric acid Correct answer.
  4. It smells of burnt hair and dissolves in hypochlorite

Explanation

Viscose rayon is regenerated cellulose, so it burns with a paper smell and is dissolved by cold concentrated sulphuric acid. These cellulosic reactions separate it from protein and synthetic fibres.

Question 34Textile Fibres and Fabric Identification

A yarn is pulled from a fabric and tested: it stretches considerably, recovers quickly and feels warm and soft. Which fibre is most consistent with this behaviour?

  1. Polyester
  2. Wool Correct answer.
  3. Cotton
  4. Linen

Explanation

Wool has natural crimp and elasticity from its helical keratin structure, giving high stretch and rapid recovery, and its scales trap air so it feels warm. Cotton and linen are relatively inelastic cellulosic fibres.

Question 35Textile Fibres and Fabric Identification

Which test is most suitable for quickly distinguishing cotton from linen in a classroom setting?

  1. Burning test, since linen chars differently from cotton
  2. Microscopic examination, since linen fibres show nodes along the fibre Correct answer.
  3. Solubility in cold hypochlorite
  4. Melting point determination

Explanation

Under the microscope, linen fibres show characteristic cross-markings or nodes along the flattened cell wall, while cotton appears as a twisted ribbon. Both are cellulosic, so burning and hypochlorite tests cannot separate them.

Question 36Textile Fibres and Fabric Identification

A fabric sample shows high strength when wet and shrinks noticeably on washing. Which fibre is most likely?

  1. Cotton Correct answer.
  2. Wool
  3. Acetate
  4. Viscose rayon

Explanation

Cotton gains strength when wet because water penetrates the cellulose and allows better hydrogen bonding, and it shrinks on washing due to relaxation of built-in strain. Regenerated and animal fibres behave differently.

Question 37Textile Fibres and Fabric Identification

A fabric is suspected to be a blend of cotton and polyester. Which approach gives the most reliable identification?

  1. Separating yarns and testing each component, or using fibre microscopy and chemical tests Correct answer.
  2. Feeling the fabric handle only
  3. Burning a single yarn and observing one flame behaviour
  4. Measuring the fabric width

Explanation

Blended fabrics show mixed reactions, so a single flame test can be misleading. Reliable identification requires separating the yarns, testing each component chemically, or examining fibres under the microscope to see both cellulosic and synthetic types.

Question 38Textile Fibres and Fabric Identification

Which weave structure gives the greatest number of interlacing points per unit area and therefore a firm, strong fabric?

  1. Plain weave Correct answer.
  2. Satin weave
  3. Twill weave
  4. Pile weave

Explanation

Plain weave has the maximum number of interlacing points because each thread crosses over and under every alternate thread. This gives a firm, stable fabric, whereas satin with long floats has fewer interlacing points.

Question 39Textile Fibres and Fabric Identification

A fabric sample is tested with a flame and gives a sweet, fruity chemical smell with a hard black bead. Which fibre group does this indicate?

  1. Protein fibres
  2. Regenerated cellulose fibres
  3. Synthetic polyester-type fibres Correct answer.
  4. Cellulosic fibres

Explanation

Polyester-type synthetics melt and drip with a sweet chemical odour and leave a hard bead that cannot be crushed. Cellulosic fibres smell of paper, and protein fibres smell of burnt hair.

Question 40Textile Fibres and Fabric Identification

A fabric is described as having a selvedge along both edges. What does this indicate about the fabric?

  1. It is a felted fabric
  2. It is a nonwoven fabric
  3. It is a woven fabric Correct answer.
  4. It is a knitted fabric

Explanation

A selvedge is the firmly woven edge formed where the weft turns back during weaving, so its presence indicates a woven fabric. Knitted and nonwoven fabrics do not have a true woven selvedge of this kind.

Question 41Textile Fibres and Fabric Identification

Which observation would help you identify the warp direction in a woven fabric?

  1. The direction parallel to the selvedge Correct answer.
  2. The direction of the diagonal twill line
  3. The direction with the softest handle
  4. The direction with more stretch

Explanation

Warp threads run parallel to the selvedge, so the selvedge gives a reliable reference for warp direction. Weft runs across the fabric at right angles to the selvedge.

Question 42Textile Fibres and Fabric Identification

A fabric is labelled as acetate. Which property would you expect from this fibre?

  1. Protein composition with burnt-hair odour
  2. Thermoplastic behaviour with low strength when wet Correct answer.
  3. High strength when wet and resistance to heat
  4. Inorganic composition with no melting point

Explanation

Acetate is a thermoplastic regenerated cellulose derivative that softens with heat and loses strength when wet. It is not a protein fibre and does not resist heat well during ironing.

Question 43Textile Fibres and Fabric Identification

Which of the following is a natural cellulosic fibre obtained from a seed?

  1. Wool
  2. Cotton Correct answer.
  3. Jute
  4. Silk

Explanation

Cotton is a natural cellulosic fibre that grows as a protective covering around the seeds of the cotton plant. Jute is a bast fibre from the stem, while wool and silk are animal protein fibres.

Question 44Textile Fibres and Fabric Identification

A fabric sample does not burn, feels cool and stiff, and is unaffected by most acids. Which fibre is most likely?

  1. Wool
  2. Cotton
  3. Acrylic
  4. Glass fibre Correct answer.

Explanation

Glass fibre is inorganic, so it does not burn, feels cool and stiff, and resists most chemicals. Organic fibres such as wool, cotton and acrylic all decompose or burn when heated.

Question 45Stain Removal and Spotting Techniques

A fresh oil stain on a cotton shirt should first be treated by which method before any washing?

  1. Ironing the fabric to lift the oil out
  2. Absorbing the excess with an absorbent powder or blotter Correct answer.
  3. Rubbing the stain vigorously with hot soapy water
  4. Applying chlorine bleach directly to the spot

Explanation

Fresh grease is best lifted by absorption before any liquid is added, because solvent or water can spread the oil further into the weave. Powder such as talc, cornstarch or fuller's earth is dusted on, left to draw out the oil, then brushed away. Only after absorption is a solvent-based spotting agent applied.

Question 46Stain Removal and Spotting Techniques

Which spotting agent is classed as a reducing bleach used to remove oxidised colour stains such as fruit and dye bleeding?

  1. Sodium hypochlorite
  2. Perchloroethylene
  3. Sodium hydrosulphite Correct answer.
  4. Amyl acetate

Explanation

Sodium hydrosulphite is a reducing bleach that removes oxidised colour matter by chemical reduction of the dye. It is used on stains such as fruit, ink and fugitive dye. It is far gentler on fibres than oxidative bleaches and is a standard spotting-kit chemical.

Question 47Stain Removal and Spotting Techniques

What is the correct order for building a spotting treatment on an unknown stain?

  1. Begin with hot water and steam, then use cold solvent
  2. Always begin with bleach, then move to solvent
  3. Start with the mildest method and escalate to stronger agents only if needed Correct answer.
  4. Start with the strongest chemical, then dilute if it works

Explanation

Spotting follows the principle of using the least aggressive treatment that will work, moving from mechanical and mild methods to stronger chemicals. This protects the fibre, the dye and the finish. Escalating only when a milder step fails avoids unnecessary damage.

Question 48Stain Removal and Spotting Techniques

A blood stain on a garment should be treated with which type of agent, and why?

  1. Cold water and a protein-digesting enzyme, because heat coagulates the protein Correct answer.
  2. Strong alkali, because blood is acidic
  3. Hot water, because heat dissolves blood quickly
  4. Chlorine bleach, because blood is a dye

Explanation

Blood is a protein stain, and heat coagulates the protein so it bonds tightly to the fibre and becomes very difficult to remove. Cold water with a proteolytic enzyme breaks the protein down safely. Hot water or strong chemicals can set the stain permanently.

Question 49Stain Removal and Spotting Techniques

Which of the following is a tannin stain that is normally treated with a tannin formula or dilute acid?

  1. Rust stains
  2. Tea and coffee stains Correct answer.
  3. Lipstick stains
  4. Chewing gum

Explanation

Tea, coffee and similar plant-derived stains contain tannins, which respond to a tannin formula or a mild acid such as acetic acid. They are not protein or grease stains and need this specific class of treatment. Recognising the stain class determines the correct spotting agent.

Question 50Stain Removal and Spotting Techniques

What does the term 'feathering' mean in spot removal?

  1. Adding a fabric patch over a hole
  2. The gradual spreading of a stain or spotting agent beyond its original boundary Correct answer.
  3. Applying starch to stiffen the fabric
  4. Trimming loose threads around a stain

Explanation

Feathering is the unwanted spreading of a stain or a spotting chemical outward into the surrounding fabric, often leaving a ring. It happens when liquid is applied too heavily or the area is not controlled. Spotting on a padded surface and working from the outside inward helps prevent it.