A care label shows a triangle with two oblique lines inside it and an iron with two dots. Which instructions follow? Select all that apply.

Only oxygen (non-chlorine) bleach may be used

Iron at a maximum of about 150 °C

Only oxygen (non-chlorine) bleach may be used

Iron at a maximum of about 150 °C

Rejecting a null hypothesis that is actually true is:

A Type I error, whose probability is alpha

A Type II error, whose probability is beta

A Type I error, whose probability is alpha

Assertion (A): A non-significant result in a hypothesis test proves that the null hypothesis is true. Reason (R): A non-significant result means only that the data were not strong enough to reject the null hypothesis at the chosen level. Choose the correct option.

Both A and R are true, and R is the correct explanation of A

Both A and R are true, but R is not the correct explanation of A

Which features are appropriate in clothing for an older adult with arthritis in the hands? Select all that apply.

Front openings with hook-and-loop or magnetic closures

Apparel Designing II: Pattern Making, Apparel Manufacturing, Apparel Quality Testing, Care and Maintenance of Clothing, Selection of Clothing and Fabrics, and Hypothesis Testing

This chapter completes Unit IV with items 5 to 10. It follows a garment from paper to wardrobe: drafting, draping and flat pattern making with dart manipulation and alterations; the industrial sequence from marker to finished garment, with seams, stitches and production systems; the quality standards, parameters and defects by which fabric and garments are accepted or rejected, including the four-point inspection system worked through; the principles of washing, the laundry agents and storage, and the care-label symbols; and the selection of clothing for different ages and of fabrics for different end uses. It closes with the Unit IV research slice, hypothesis testing: what a hypothesis is, its types and scope, and the logic and errors of testing it.

1. Pattern making: drafting, draping, flat pattern, alteration and dart manipulation

There are three ways to make a pattern. Drafting constructs it on paper from body measurements and ease allowances, beginning with basic blocks (slopers) for the bodice, sleeve and skirt. Draping shapes fabric, usually muslin, directly on a dress form, then transfers the markings to paper; it suits soft, fluid and asymmetric designs. Flat pattern making develops new styles by manipulating an existing block, and is the method of the industry because it is fast and accurate. Every pattern carries grain lines, notches, seam allowances (commonly 1.5 cm on home-sewing patterns), darts and labels, and includes ease: wearing ease for movement and design ease for the intended silhouette.

Darts shape flat fabric to the curves of the body. The bust dart can be moved anywhere around the bust point (apex) without changing the fit, because what matters is the angle of fabric removed, not where it is removed. Two techniques do this: the pivot method, rotating the pattern about the apex, and the slash-and-spread method, cutting to the apex, closing the old dart and opening a new one. The dart's fullness can also be converted into dart equivalents: tucks, gathers, pleats or style lines such as the princess seam. Pattern alterations adapt a standard pattern to an individual figure by lengthening or shortening along alteration lines and by slashing and spreading or folding and overlapping for problems such as a full bust, a sway back, round shoulders or sloping shoulders. Grading, the reverse of fitting one person, scales a pattern up and down to a range of sizes, now largely on computer.

🧠 All darts point to the apex

Whether the bust dart comes from the shoulder, the armhole, the neckline, the side seam or the waist, its point aims at the bust point and stops a little short of it. Moving a dart changes style, not fit.

2. Apparel manufacturing

Industrial production runs from design and sampling to pattern making and grading, marker making, spreading, cutting, bundling and ticketing, sewing, finishing (thread trimming, pressing, fusing), inspection, and folding and packing. The marker is the layout of all pattern pieces for one or more garments on the fabric; marker efficiency is the area of the pattern pieces divided by the area of the marker, multiplied by 100, so pieces totalling 3.6 square metres on a 4.5-square-metre marker give 80 per cent. Fabric is spread in many plies, face to face or all face one way, and cut with straight knives, band knives, die cutters or computer-controlled cutters, and for some fabrics laser or water jet.

Seam	Construction	Typical use
Plain seam	Two layers stitched right sides together, edges finished	Most garments
French seam	Stitched first wrong sides together, trimmed, then enclosed by a second seam	Sheer fabrics, where raw edges would show
Flat-felled seam	One allowance folded over the other and stitched flat twice	Jeans and shirts: strong and self-finished
Lapped, bound and piped seams	One edge laps over another; edges bound in tape; a cord inserted	Yokes; unlined jackets; decorative edges

Progressive bundle system: cut parts move in bundles from operator to operator, each doing one operation; high output, high work-in-progress.
Unit production system: an overhead conveyor carries all the parts of one garment to each workstation, cutting handling time.
Modular (team) system: a small, multi-skilled team completes whole garments, giving flexibility for small orders.
Make-through (whole garment): one operator sews an entire garment, as in tailoring and sampling.

3. Apparel quality testing: standards, parameters and defects

Quality means conformance to specification. Standards come from national and international bodies (BIS, ISO, ASTM, AATCC) and, in export trade, from buyers' own specifications and tech packs, which fix measurements and tolerances, fabric and trim requirements, stitches per inch, seam types and test methods. Fabric parameters include GSM, construction, shrinkage, colourfastness and strength; garment parameters include measurements within tolerance, seam strength and seam slippage, stitch density, puckering, symmetry, shade matching and correct labelling.

Fabric defects	Garment defects
Slubs, holes, broken ends and picks, floats	Skipped and broken stitches, open seams
Barré (unintended stripes), shade variation, bowing and skewing of weft	Seam puckering, uneven hems, mismatched checks and stripes
Oil and dirt stains, selvedge defects	Wrong or missing labels, shading between panels, measurement out of tolerance

Fabric is inspected most often by the four-point system: each defect earns 1 point if up to 3 inches long, 2 points if over 3 and up to 6 inches, 3 points if over 6 and up to 9 inches, and 4 points if longer than 9 inches or a hole, with no more than 4 points for any one linear yard. Points are normalised to 100 square yards: points per 100 sq yd = total points × 3600 / (yards inspected × fabric width in inches). If 100 yards of 60-inch fabric carry 30 points, the score is 30 × 3600 / (100 × 60) = 18, well within the 40 points often used as an acceptance limit. Finished garments are usually inspected by acceptable quality level (AQL) sampling plans under ISO 2859-1.

4. Care and maintenance of clothing, and selection of clothing and fabrics

Washing removes soil by combining four factors, often drawn as a circle: chemical action (detergent), temperature, time and mechanical action; less of one must be made up by more of the others. Soaps are sodium or potassium salts of fatty acids and form scum in hard water; synthetic detergents work in hard water and are built from surfactants (anionic, non-ionic, cationic for softeners), builders that soften water, enzymes (protease for protein stains, amylase for starch, lipase for fat, cellulase for fuzz), optical brighteners and perfumes. Bleaches are chlorine-based (sodium hypochlorite, unsuitable for wool, silk and elastane) or oxygen-based (hydrogen peroxide, sodium perborate or percarbonate, safer for colours). Blue, starch and fabric softeners are finishing agents. Stains are treated fresh, identified first, tested on a hidden area, and worked from the outside in. Clothes are stored clean and dry, woollens with moth repellents such as neem leaves or naphthalene, knits folded rather than hung, and silks away from light.

Care symbol (ISO 3758)	Meaning
Washtub	Washing; a number gives the maximum temperature, a hand in the tub means hand wash, bars beneath mean a milder process, a cross means do not wash
Triangle	Bleaching; empty means any bleach, two oblique lines mean oxygen (non-chlorine) bleach only, crossed means do not bleach
Square	Drying; a circle inside means tumble drying, with dots for heat
Iron	One dot: up to 110 °C; two dots: up to 150 °C; three dots: up to 200 °C
Circle	Professional textile care; letters indicate dry cleaning solvents or professional wet cleaning

Infants: soft, absorbent, easily washed fabrics; front or shoulder openings; no small buttons or drawstrings that could be swallowed or strangle; flame-resistant sleepwear.
Toddlers and preschoolers: self-help features (large buttons, elastic waists, front openings), growth features (adjustable straps, deep hems), durability.
School-age children and adolescents: durability and ease of care, peer acceptance, and for adolescents clothing as an expression of identity.
Adults: occupation, figure, budget, occasion and climate.
Older adults and persons with disabilities: easy dressing (front openings, hook-and-loop or magnetic closures, elastic waists), warmth, comfort, non-slip footwear; adaptive clothing for wheelchair users.
Fabrics for end uses: absorbent cotton and linen for summer, insulating wool for winter, moisture-wicking polyester with elastane for sportswear, durable polyester-cotton blends for uniforms, and heavier, fade-resistant fabrics for furnishings.

5. Research methods IV: hypothesis testing, types and scope

A hypothesis is a tentative, testable statement of the expected relationship between two or more variables, derived from theory, earlier research or observation and stated before the data are collected. A good hypothesis is clear and specific, testable with available methods, consistent with known facts, limited in scope, and stated in terms of variables that can be measured. Its scope is to direct the study: it tells the researcher what data to collect, which design and sample to use, and which statistical test will decide the question. Types and designs came in chapters 5 and 8; the statistics that the tests rest on come in chapter 18, and the tests themselves in chapter 20.

Type of hypothesis	Example
Research (substantive) hypothesis	Mothers who receive nutrition counselling feed more diverse diets to their children
Null hypothesis (H0)	There is no difference in dietary diversity between counselled and uncounselled groups
Alternative hypothesis (H1), non-directional (two-tailed)	Dietary diversity differs between the groups
Alternative hypothesis (H1), directional (one-tailed)	Dietary diversity is higher in the counselled group
Descriptive, relational and causal hypotheses	About the level of a variable; an association between variables; a cause-and-effect claim

Testing proceeds in steps: state H0 and H1; choose the level of significance (alpha), usually 0.05 or 0.01; choose the test statistic suited to the data and design; find the critical region; compute the statistic from the sample; and reject H0 if the statistic falls in the critical region (equivalently, if the p-value is below alpha), otherwise fail to reject it. For a z-test at alpha = 0.05 the critical values are ±1.96 two-tailed and 1.645 one-tailed; at 0.01 they are ±2.58 two-tailed. Worked: a sample of 64 has a mean of 52 where the population mean is 50 and the standard deviation 8; the standard error is 8 / √64 = 1, so z = (52 − 50) / 1 = 2.0, which exceeds 1.96, and H0 is rejected at the 0.05 level (two-tailed).

Decision	H0 actually true	H0 actually false
Reject H0	Type I error (probability alpha)	Correct decision (probability 1 − beta, the power)
Fail to reject H0	Correct decision (probability 1 − alpha)	Type II error (probability beta)

⚠️ "Fail to reject" is not "accept"

A non-significant result means the data were not strong enough to reject H0, not that H0 is proved. Lowering alpha from 0.05 to 0.01 reduces Type I errors but, for the same sample, raises Type II errors; a larger sample raises power and lowers both.

Key takeaways

Patterns are drafted, draped or developed by flat pattern methods; darts move around the apex by pivoting or slash-and-spread and convert into tucks, gathers, pleats and style lines.
Production runs marker, spreading, cutting, bundling, sewing, finishing and inspection; marker efficiency = pattern area / marker area × 100; French seams suit sheers and flat-felled seams jeans.
The four-point system scores defects 1 to 4 by length; points per 100 sq yd = total points × 3600 / (yards × width in inches).
Washing balances chemistry, temperature, time and mechanical action; care symbols are the washtub, triangle, square, iron (1, 2, 3 dots = 110, 150, 200 °C) and circle.
A hypothesis is a testable prediction; H0 is rejected when the statistic falls in the critical region; Type I error has probability alpha, Type II beta, and power is 1 − beta.

Practice questions (10)

Attempt each one before opening the answer. Every explanation names the tempting wrong option as well as the right one, because that is where marks are lost.

In a four-point fabric inspection, 100 yards of 60-inch-wide fabric accumulate 30 penalty points. What is the score in points per 100 square yards? Type the number.
Numerical answer — type the value.
Show answer
Answer: 18
Points per 100 sq yd = 30 × 3600 / (100 × 60) = 108,000 / 6,000 = 18. The factor 3600 converts inches of width and yards of length into square yards and scales to 100.
The pattern pieces in a marker have a total area of 3.6 square metres and the marker itself covers 4.5 square metres. What is the marker efficiency in per cent? Type the number.
Numerical answer — type the value.
Show answer
Answer: 80
Marker efficiency = 3.6 / 4.5 × 100 = 80 per cent; the remaining 20 per cent of the fabric in the marker is waste between pieces.
Which seam encloses the raw edges and is preferred for sheer fabrics?
1. Plain seam with pinked edges
2. French seam
3. Piped seam
4. Lapped seam
Show answer
Answer: B — French seam
The French seam is sewn twice, first with wrong sides together and then enclosing the trimmed edges, so nothing shows through a sheer fabric. A pinked plain seam leaves visible raw edges, and lapped and piped seams are structural or decorative choices.
In flat pattern making, moving a bust dart from the side seam to the shoulder by cutting to the bust point, closing the side dart and opening a new one is the:
1. Slash-and-spread method
2. Draping method
3. Drafting method
4. Grading method
Show answer
Answer: A — Slash-and-spread method
Slashing to the apex, closing one dart and spreading to open another is the slash-and-spread technique of dart manipulation; the pivot method achieves the same by rotating the block. Draping works on a dress form, grading changes size and drafting builds a block from measurements.
A care label shows a triangle with two oblique lines inside it and an iron with two dots. Which instructions follow? Select all that apply.
1. Only oxygen (non-chlorine) bleach may be used
2. Do not iron
3. Chlorine bleach is recommended
4. Iron at a maximum of about 150 °C
Show answer
Answer: A — Only oxygen (non-chlorine) bleach may be used; D — Iron at a maximum of about 150 °C
Two oblique lines in the triangle restrict bleaching to oxygen, non-chlorine bleach, and two dots on the iron set a maximum sole-plate temperature of about 150 °C. An empty triangle would allow any bleach and a crossed iron would forbid ironing.
Which enzyme in a detergent is aimed at stains such as blood, egg and milk?
1. Cellulase
2. Amylase
3. Lipase
4. Protease
Show answer
Answer: D — Protease
Blood, egg and milk stains are protein-based, which protease breaks down. Amylase targets starch, lipase fats and oils, and cellulase acts on cotton fibres to remove fuzz and brighten colours.
A sample of 64 children has a mean height gain of 52 mm where the population mean is 50 mm and the population standard deviation 8 mm. What is the z value? Type it as a whole number.
Numerical answer — type the value.
Show answer
Answer: 2
Standard error = 8 / √64 = 8 / 8 = 1, so z = (52 − 50) / 1 = 2.0. Because 2.0 exceeds 1.96, H0 is rejected at the 0.05 level in a two-tailed test.
Rejecting a null hypothesis that is actually true is:
1. A Type II error, whose probability is beta
2. A correct decision
3. The power of the test
4. A Type I error, whose probability is alpha
Show answer
Answer: D — A Type I error, whose probability is alpha
A Type I error is a false positive: rejecting a true H0, with probability equal to the chosen significance level alpha. A Type II error fails to reject a false H0, and power is the probability of correctly rejecting a false H0.
Assertion (A): A non-significant result in a hypothesis test proves that the null hypothesis is true. Reason (R): A non-significant result means only that the data were not strong enough to reject the null hypothesis at the chosen level. Choose the correct option.
1. Both A and R are true, and R is the correct explanation of A
2. Both A and R are true, but R is not the correct explanation of A
3. A is true, but R is false
4. A is false, but R is true
Show answer
Answer: D — A is false, but R is true
A is false and R is true. Failing to reject H0 is not the same as proving it: a small sample or a small effect can leave a real difference undetected, which is a Type II error. The correct wording is "fail to reject", never "accept as proved".
Which features are appropriate in clothing for an older adult with arthritis in the hands? Select all that apply.
1. Elastic waistbands
2. Small buttons at the back
3. Tight, non-stretch sleeves
4. Front openings with hook-and-loop or magnetic closures
Show answer
Answer: A — Elastic waistbands; D — Front openings with hook-and-loop or magnetic closures
Front openings with easy closures and elastic waists reduce the fine finger movements that arthritis makes painful. Small back buttons and tight non-stretch sleeves make dressing harder and are what adaptive clothing avoids.