3. 1. PLAN OF THE OVERALL FUNCTION OF QUALITY
CONTROL
• The cost of quality
• Functions of Quality Assurance
• Commercial advantages form effective
control systems
• Economic aspects of quality assurance
• The role of quality control
4. 2. THE ROLE OF QUALITY CONTROL IN
THE CONTEXT OF QUALITY
MANAGEMENT
• Outline of quality control systems
requirements
• Data generated
• British Standard 5750
5. 3. FINAL PRODUCT SPECIFICATIONS
• Quality control in the sampling/development
department
• From sample to full production
• The Specification layout
• Process specification
• Sample garment specification
• Seam specification
• Performance specification
6. 4. THE MAIN RAW MATERIAL - FABRIC
• Fabric and garment dimensions - fabric
stability and finished width
• Fabric inspection - examination of fabric
on receipt
7. 5. BASIC SEAMING TECHNOLOGY
• Basic technology of seams
• Stitch forming action
• Quality checks on seams
9. 6. QUALITY MONITORING THROUGH
CUTTING AND GARMENT ASSEMBLY
7.1 Recording
• Recording systems - making up
• Supervisors check list
10. 7.2 Tolerances
• Tolerance limits
7.3 The threshold of faults
• Training quality standards and faults
analysis
7.4 Sampling techniques
• Checking levels of faults and seconds
11. 7.5 Technology if Inspection
• Garment examination
• Seeing colour and the effect of type of
illuminant on the apparent shade of a
sample
• Effects of intensity, angle of illumination
and type on the apparent shade of a
sample
• Effects on shade of other colours in
adjacent areas
• Mounting and displaying for viewing
• Colour vision
12. 7.6 checking operatives and examiners
• Assessment of operative effectiveness
from records
• The supervisor and quality control
• Weather trials
7.7 Auditing Boxed Stock
• Boxed Stock Quality Audit
13. 8. QUALITY COMMUNICATIONS
• Control of quality in garment assembly
• Example of quality feedback - marks and
stains
• Action checklist to improve garment
cleanliness
• economics of cleanliness
• Fault cost assessment record
• Quality Control Requirements - Order of
Priorities
14. "Quality" is defined as that combination of
design and properties of materials of a
product which are needed for the intended
end use and level of the market in which it is
sold.
"Requisite Quality" is defined as the
design and composition of a product, which
has been thoroughly proved by adequate
development work, in order to establish its
reliability under the conditions to which it will
be subjected in use and to avoid producing
too high a grade of product for the intended
market.
15. Quality Assurance
"The establishment and maintenance of ALL
activities and functions concerned with the
attainment of requisite quality"
Quality Control
"The systems required for programming and
co-ordinating the efforts of the various
groups in an organisation to maintain the
requisite quality" As such Quality Control is
seen as the agent of Quality Assurance or
Total Quality Control
16. Quality for textile and apparel:
Quality may be defined as the level of
acceptance of goods or services.
For the textile and apparel industry, product
quality is calculated in terms of quality and
standard of fibers, yarns, fabric construction,
colour fastness, designs and the final finished
garments. Quality control in terms of garment
manufacturing, pre-sales and posts
17. sales service, delivery, pricing, etc are essential
for any garment manufacturer, trader or
exporter.
Certain quality related problems, often seen in
garment manufacturing like sewing, colour,
sizing, or garment defects should never be over
looked.
These defects are discussed below -
18. Sewing defects
Open seams, wrong stitching techniques, nonmatching threads, missing stitches, improper
creasing of the garment, improper thread
tension etc. are some of the sewing defects
which can affect the garment quality adversely.
19. Colour defects
Variation of colour between the sample and the
final garment, wrong colour combinations and
mismatching dyes should always be avoided.
20. Sizing defects
Wrong gradation of sizes, difference in
measurement of various parts of a garment like
sleeves of XL size for body of L size garment
can deteriorate the garments beyond repair.
21. Garment defects
Broken or defective buttons, snaps, stitches,
different shades within the same garment,
dropped stitches, exposed notches, fabric
defects, holes, faulty zippers, loose or hanging
sewing threads, misaligned buttons and holes,
missing buttons, needle cuts, pulled or loose
yarn,
22. stains, unfinished buttonhole, short zippers,
inappropriate trimmings etc. all can lead to the
end of a brand name even before its
establishment.
23. Some of main fabric properties that are
taken into consideration for garment
manufacturing for export basis:
• Overall look of the garment.
• Right formation of the garment.
24. • Feel and fall of the garment.
• Physical properties.
• Colour fastness of the garment.
• Finishing properties
• Presentation of the final produced garment.
25. Methods of quality control:
Basically two methods are used for garments
quality control –
i) Testing
ii) Inspection.
Maximum garments manufacturers apply
inspection method due to high cost of testing
equipments.
26. Inspection:
Inspection may be defined as the
visual examination in relation to some standards.
Objective:
The main objectives of inspection are –
i. Detection of defects.
ii. Correcting the defects or defective
garments.
27. • To inspect garments an integral method
named ‘Inspection Loop’ is used given
below –
Inspection
Correction of the defects
Detection of defects
Inform defects to
appropriate personnel
Determination of
causes of defects
Fig: Inspection Loop.
28. Steps of inspection in garments industry:
i) Raw materials inspection (Fabric
and Accessories)
ii) In Process inspection.
iii) Final inspection.
29. Raw Materials
•
•
Shade - checked to be within tolerance
of standard pattern.
Delivery weights - checked and any
shortfall claimed.
30. Fabric Parameters, Fabric or Garment Blank
Checks :
• Shade and appearance correct jacquard pattern
correct, absence of barrenness.
• Width normal - (this is only a guide with grey fabric).
• Fabric weights per square metre (or preferably weight
per predetermined revs) - checked to within tolerance
of specification.
• Blank weight per dozen to be within tolerance of
specification.
• Check fabric for faults and stains.
• Finishing loss - on-going record of losses on scouring
etc.
• Accountability of knitters.
31. Sewing thread inspection:
A) Thread construction:
To know about thread
construction the following should be tested –
i. Thread count.
ii. Thread ply.
iii. Number of twist.
iv. Thread balance.
v. Thread tenacity.
vi. Thread elongation
32. B) Sew ability:
The sewing ability of a thread is
called sew ability. During sew ability test
the following quality of thread should be
tested –
i. Imperfection
ii. Finish
iii. Package density
iv. Winding
v. Yardage
33. What are the things used to check to
determine the quality of Zipper:
i. Measuring Zipper Dimension
ii. Top and Bottom stops should be secured
iii. Uniform in color
iv. Slider should ride freely but not so free
v. Slider lock must be secured.
vi. Durability of finish of zipper chain to
laundering or dry cleaning.
vi. Color fastness to zipper to light, to
crocking (rubbing) and to laundering.
34. In-process Inspection
Sewing Checks
•
•
•
•
•
Stitches per cm. and thread run-in ratio
checked to be within tolerance of
specification.
Evenness, balance and correct bight, no
stitching missed
Extensibility and security correct (i.e. no
cracking or laddering).
Absence of skip stitching.
Accountability of machinist.
35. Final Inspection
•
•
•
•
•
•
•
•
Shade correct and not varying from one part of
garment to another.
Cut is correct - e.g. neck, collar and sleeves
balanced, pockets correct.
Measurements within tolerance of specification,
weight correct.
Appearance correct, patterns matching.
Seams finished correctly, absence of miss stitching,
cracking and laddering.
Accessories correctly applied and working.
Absence of fabric faults and stains.
Correct labelling.
37. Product Tests
•
Colour fastness to agreed agencies: (e.g.
washing, rubbing, perspiration, lights) - checked
and on-going continuity cards generated, showing
rating, checked against specification.
• Stability:
• Shrinkage, and extension recovery where needed
- to be within tolerance of specification
• Endurance:
• Abrasion, pilling or snagging - tested where
needed. Rating checked against specification
• Flammability:
Performance rating in appropriate test checked
against specification.
38. AQL Random Sampling Inspection
# The AQL inspection takes the
samples from a goods, inspect
them and depends on the quality of
samples inspected and decide to
accept or reject them.
# The standard is based on Military
Standard 105D (MIL-STD-105D)
39. # It provides with the sampling plans,
the number of samples to be
inspected and the acceptable
quality level (AQL)
# AQL 1.5 is applied to very severe
inspection on high-class expensive
item.
# AQL 2.5 is applied when textiles of
normal/good quality are involved.
40. AQL (II)
# Three types of sampling plans
-single, double and multiple.
# Each sampling plan can be
performed in three levelnormal, tightened and reduced,
depending on quality of products.
# In garment industry, single and
double normal sampling plans are
applied.
41. Sample Size Code Letter
• The Sample Size Code Letter shows
different lot sizes to different code letter.
• There are seven inspection level, four for
general inspection and three for special
inspection
• For garment inspection, General
Inspection level II would be used.
45. Example
Single Sampling Plan-Normal Inspection
• Assume AQL is 2.5% and lot size is 600
garments, find out the following :
– The total number of samples need to
inspect
– The acceptable number of the samples
– The rejection number of the samples
46. Answer
Single Sampling Plan
• First, from Table 1 find out the code letter
for lot size of 600 and inspection level II is
“J”
• From Table 2 (single sampling plan), the
letter “J” corresponds to sample sizes of
“80”.
• So, 80 samples are needed to inspect out
of 600
• At AQL 2.5%, if defective garments are
less than or equal to 5, whole lots will be
accepted, if it is found to be 6 or more,
whole lots will be rejected.
47. Try this one
• If the garment lot is 300 dozens, and AQL
is 4.0%, find out
• the number of samples to be inspected
• the acceptable number and rejection
number
48. Example II
Double Sampling Plan
• Assume AQL is 4% and lot size is 2000
garments, find out from double sampling
plan on the following:
– The total sample sizes need to inspect
– What is the first acceptable number
– What is the second acceptable number
49. Answer
Double Sampling Plan
• First, Table 1 of 2000 lots at inspection
level II is letter “K”
• Table 3, double sampling plan shows the
sample size of letter K is 80.
• First inspection, at AQL 4%, the
acceptable number is 5, rejection number
is 9
• If any number between 5 to 9, second
inspection is needed
50. Answer
Double sampling Plan (II)
• For second inspection, the sample sizes
again is 80
• At AQL 4%, the cumulated acceptable
number is 12 and rejection number is 13.
• Conclusion
– If the number of defective garments found
in the first sample is 6, and in second
sample is 5, making a total of 11, then the
whole lot of 2,000 pieces will be accepted.
51. References
• Garments and Technology
Prof. M. A. Kashem
• Jimmy K.C. Lam
The Hong Kong Polytechnic University
• Introduction to garments manufacturing
Harold Carr
• Fashion dictionary
• Engr. Mohammad Faizur Rahman (Rashed),
Assistant Professor (Garments Technology),
Department of Textile Technology, AUST
