Work measurement is used to determine the time
required to complete one element or one. Work measurement techniques -used by
garment manufacturers include
- Time studies
- Judgment
- Predetermined motion time systems
- Standard data
- Operator reporting
- Work sampling.
Each work measurement technique has advantages and
disadvantages for specific applications.
1. Time Study
Time study is
a work measurement technique commonly used by apparel engineers to determine
the rate at which a specific operation is performed. The objective of a time
study is to develop and check production standards. An operation is studied by
time analysts while a style is in production. A time study requires a method
description for the specific operation to determine the work elements involved,
the order in which they occur, the time required to complete each element, and
the rate at which a particular operator is working. Time studies are an
appropriate method of work measurement for high-volume operations with a high
degree of repetitiveness. They are frequently used to establish production
standards for operations performed in a progressive bundle system.
2. Judgment
For some
apparel manufacturers, time studies may be too time- consuming and costly. For
small fashion manufacturers with rapidly changing product lines and short runs
or small custom orders, a style may not be in production long enough to conduct
time studies. Small firms may find it economically unfeasible to employ a time
study analyst. Instead, smaller firms may rely on the judgment of managers or
supervisors for time estimates. This method can provide only approximate time
values, and it is not advocated if there is another more accurate means of
gathering the needed information.
3. Predetermined
Motion Time Systems
Predetermined
motion/time systems are used by many firms to establish production standards
for new styles before the style goes into production. The basis of these
systems is historic data for hundreds of replications of basic motions and
elemental times that have been averaged and converted to standard times for a
specific motion. This method of work measurement produces the most consistent
production standards. With
predetermined motion/time systems, rates are based on the time to execute a
method. This forces engineers to examine equipment, layout of workstations, and
handling of parts at the workstation. The method or
motion sequence is established first, and the time value or rate is identified
for the motions specified. Engineering specifications identify the specific
method that an operator is expected to follow. Generally, this causes more
effective use of direct labor and thus more accurate rates.
There are a
number of different motion-time systems. General Sewing Data (GSD), MODSEW,
KARAT, and other similar systems identify time values for specific motions
required in garment production. These are available as computer software that
manufacturers can purchase. Engineers that use these systems must be well
trained in identifying the specific motions that are involved in each
operation.
4. Standard
Data
Frequently
firms collect their own data for repetitive operations with similar
characteristics and develop their own standard data sets for specific
operations. These data are used in the same way as predetermined motion/time
data except the data sets are specific to the firm’s quality standards, equipment,
and procedures. A firm must have an adequate database before trying to use its
own standard data. Standard data may be developed for operations, components,
and styles and can be used for preliminary costing, design decisions, cost
estimating, and rate setting.
5. Operator
Reporting
Operator
reporting relates to the volume completed during the time spent. Operators
report the amount they complete in a specific time period. There are no
specified methods or output expectations; therefore, it is difficult to use
operator reporting as a basis for production standards or for capacity
planning. Cost figures are determined by dividing the number of units completed
in an hour with the hourly wage. The amount of work completed in a specific
time frame is often inconsistent and may be unreliable. This type of work
measurement provides very little information and little incentive for
increasing work efficiency. It may be the method used by firms that produce
customized products in small volume and wide variety.
6. Work
sampling
Work sampling
is a work measurement method concerned with which machines are used and the
activities pursued in executing the job in an established period of time. It is
based on simple random sampling techniques derived from statistical sampling
theory. When production standards are needed for operations that are not highly
repetitive, work sampling is a good choice. The analyst determines the
activities involved, amount of time spent on the various activities, equipment
used, and number of units processed during an established time period. This
type of work measurement is particularly useful in examining the productivity
of non-production areas such as the shipping room. The manager can estimate the
proportion of time a worker is engaged in work activity. This proportion can
then be used as a performance standard.