The 3rd Intl. Workshop on NL-based Software Engineering
Traffic light system
1. Traffic Light System
Traffic Light System - A Visual Quality Control Tool
Introduction
Garments styles are changing rapidly. Also the fast changing economic conditions such
as global competition, declining profit margin, customer demand for high quality
product, product variety and reduced leadtime etc. had a major impact on
manufacturing industries. The demand for higher value at lower price is increasing and
to survive, apparel manufacturers need to improve their operations through producing
right first time quality and waste reduction. Unless buyer’s expectations and
requirements are met, it would be very difficult to survive or to grow. Therefore, quality
is becoming a vital key to successful growth of a company. Reworks in the garments
industry are a common work that hampers the smooth production rate. Rework is a vital
issue for poor quality product and low production rate. Stitching operations (with
respect to cutting and finishing) needs high skill as well as quality work, because of
difficulty associated with repairing of products sewed with wrong specifications. We
have to give more attention to stitching than to cutting and finishing. Here, how a traffic
light system in sewing floor can be used to detect defects at source level is described.
What Is Traffic Light System
Traffic light system is the most effective inspection tool to reduce defect generation at
source.
This is a random inspection system. Traffic light system is more effective in controlling
shop floor quality than other quality tools because of its visual communication. At the
same time it measure operator’s performance level in quality. No operators like to be
presented themselves as lower quality makers. They concentrate on quality aspect
during stitching garments.
Inline checking system will alert operators in concentrating their job. If less number of
defective seams is made, less the time will be lost in repairing it. It also helps in other
way. May be at the start of the style an operator do not understand the specification, an
interaction with quality inspector will make an operator clear about the quality
requirement. Traffic Light System is designed to flag the problem at source and allow
immediate corrective action rather than all potentially defective products to continue to
be manufactured.
2. How It Works
Traffic Light System is a visual control for highlighting quality issues in sewing line.
Traffic light quality system works in a similar fashion the transportation traffic light
system works. Three different color cards are placed in each operators place. Green
indicates that Quality meets the customers Standard. Yellow indicates that a minor fault
has been found and caution is required. Red indicates that the Quality Standard does
not meet the customer’s standard requirement.
3. One Inline Quality Checker is to be allocated for every line of particular style or cover 15
or 20 Workstations. She/he has to check the semi finished garment pieces from current
bundle once in an hour or two. Pieces will be taken randomly and check all the quality
parameters required for that operation. Stitches per inch, seam width, sewing
allowance, correct trims and their placement and measurement etc are to be verified by
the Inline Quality checker. While inspecting, depending upon the quality level, color
cards are placed on their machine.
The red card is given for those, who are identified by the line supervisor have produced
5 or more defective item out of ten pieces inspected. The yellow card is given to those
who are identified by the line supervisor have produced 2 or more defective items out of
ten inspected. The green card is given if no reworks are found. This can motivate the
worker to produce good quality products. It is also an indication of how and which
operator is going wrong to the production in charge and quality supervisor. They can
monitor from any corner of the floor easily.
Number of pieces to be checked and limit of number of defect pieces for color code
change slightly differs in different factories depending upon the quality level they target.
But when any worker who does multiple faults, a red card is hanged above his or her
head that indicates that this worker is producing several faults that should be corrected
and an extra care should be taken to this worker. The extra care may be in a way that he
or she should be trained for that operation or if there have any problem, could be solved.
The format shown below is used for a single operator or workstation. A single sheet will
keep record for the whole month for an operator. Inline Quality checker, on the first day
of the month have to fill details such as Operator name, Line number and name of the
Month. The format is displayed in two sections (front & back) to cover 31 days (whole
month). Each row contains space to cover hourly inspections in a shift. The space is
filled with respective color pen. At the end of the day quality auditor /supervisor has to
sign in the report. At the end of month, performance of operator can be easily noted
form color filled columns.
4. Employee Motivation
The system offers that, the best worker and the best line that scored highest should be
honored by the management and some incentive should be given to them for their
outstanding performance. The system also offers that, they should also be honored by
being put a best quality badge for the whole month so that they could feel proud and all
other workers could inspire to achieve the highest quality level. It is practiced by lot of
factories nowadays and they find improvement in employee performance.
Success Stories
QAM. Imran Ali reported that about 5% production capacity has been increased through
quality improvement system when they implemented traffic light system in a company
at Karachi Pk. The monthly capacity before implementing the traffic light system was
equivalent to 925 days production of one line for a month whereas after the system
being implemented it reduced to 878 days with an improvement of 47 days production
capacity.
5. In a study conducted by group of students after implementing traffic light system at
Artistic Milliners Garments Karachi, it is reported that the rework percentage has
reduced from 2.14 % to 1.01 % in the sewing Line.
Conclusion
Traffic light system is a system that can be implemented easily in any garment
manufacturing company and it will help to improve the quality status, reduced the cost,
improve the lead time and thus strengthen the supply chain performance without
increasing the resource. Poorly managed factory loses productivity up to 10% due to
repair and reject. Hence implementation of traffic light system will help to get more
quality products from Operators of this age.
References
1. www.artisticmilliners.com
2. Traffic Light Quality management system, QMS Mgr. Imran Ali and Asst Mgr. Aarifa
Anis.
3. Productivity in Pakistan Apparel Industry.