WORK STUDY

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WORK STUDY Work Study is the systematic investigation of

the methods of carrying out activities. To improve the effective use of resources. To set up standards of performance for the

activities carried out.

Work Study-Components of Work StudyWork-study consists of 2 main components: method study, work measurement,

High

Productivity

WORK STUDY

Widely used in in manufacturing industry. Applying work study in construction is much

harder and more expensive. Each project has its own unique characteristics. Information collected are often un reliable.

There are other variables such as: weather, ground condition,

WORK STUDY

location, Labour force skill, shortage of skilled workers etc They all can effect work study. Work study is a powerful tool for collecting

information for analysis.

WORK STUDY The result of the survey can be used for planning

and better control of labour, material and machinery etc.

accurate data for achieving KPIs, better estimating, improved planning, financial incentive for good workers, Method study It is a systematic recording of site variables such

as;

METHOD STUDY

Labour, Materials, Machinery, Site congestion Etc The result of the study should provide accurate

information for management team to improve site efficiency and productivity.

By applying better, easier and efficient way of carrying out a task on site.

METHOD STUDY

There are some areas on construction site which can be identified, investigated and improved.

This can be achieved by the introduction of method study.

The source of decline on construction site is considered to be high.

They might manifest themselves in the following shape as illustrated in the diagram.

WORK STUDY-THE PROCESS

METHOD STUDY

Method study can also be described as: A method that is used to analyse and

reduce ineffective methods or costs. There are several steps by which this can

be achieved, these steps are as follow: Step one:Define problem Step two:Record all facts Step three: Analyse all data recorded

WORK STUDY Step four: Propose appropriate course of

action Step five:Put proposal into action Step six: Monitor the changes made

The objectives of method study are asfollow:  Is to improve the use of materials,

manpower and equipment.

METHOD STUDY To improve processes and procedures. To improve the layout of the construction

site. To improve the design of tools and

equipment. To improve frequent plant breakdown. To reduce errors and mistakes. To reduce unnecessary work. To improve the work environment.

METHOD STUDY

To reduce fatiguing work.To reduce shortage of resources.To have full control of all activities

on site.To reduce delays on site, including

delays made by sub-contractors.To reduce site congestion.

WORK MEASUREMENT

WORK MEASUREMENT  Work measurement is a method, which

uses time study to find out how long it should take to complete a task.

It is defined in BS 3138:1969 as a technique designed to measure the time required for a skilled worker to fulfil a task at a defined level of performance/pace.

WORK MEASUREMENT The aim of work measurement is to record

procedures. Also, to produce standard time for a given task

on the site. This is a standard time that a skilled worker

needs to complete a task. Standard time is a good measure of performance. It is a useful tool for estimating, planning and

controlling activities on site. The disadvantages of work measurement-it is

very expensive to operate.

WORK MEASUREMENT

Procedure Step 1- Select the work to be measured. Step 2- Define the method being used and the job

elements. Step 3- Measure the quantity of the work and

assess the rating. Step 3- Calculate the standard time including all

allowances. Compile and issue the allowed time with a job

specification.

WORK MEASUREMENTDefinitions Timing is usually stopwatch by intervals of 1/5th

second, 1/100th min or 1/10, 000 hours. Continuous timing-in continues or cumulative

timing the watch is started at the beginning of the first element and is not stopped until the whole study is completed.

Repetitive or fly-back timing The time is simultaneously read and snapped

back to zero at the end of each element. 

WORK MEASUREMENT Rating Time study is based on a record of the observed

times for carrying out a task. Together with an assessment of the effectiveness

of working of the worker. This optimum effectiveness will enable operative

to produce without becoming more than healthily tired or standard performance.

A scale has been fixed to give this ideal of effectiveness a value of 100.

WORK MEASUREMENT

Standard rating Observers are well trained to be able to recognise

the conditions of standard rating. This is to allow them to assess to the nearest 5

points the degree to which a worker’s observed speed and effectiveness vary from the 100 concept.

Normal or Basic Time= Observed Time X Observed Rating/ Standard Rating

WORK MEASUREMENT

Relaxation allowances So far all idle time and relaxation periods have

been excluded from observations. It is important to add certain allowances in order

to have an accurate standard for the proper performance of the measured work.

Therefore allowances most be added to basic time.

These alliances are; Energy output

WORK MEASUREMENT Posture Motions Visual fatigue Personal needs Weather temperature Air pressure-confined space Other factors

WORK MEASUREMENTContingency allowancesIn some circumstances other allowances are alsoincluded such as; delay cause or interferences by other trade, plant breakdown or difficulties caused by the

organization. During time study if un- usual events have

occurred, the study must be stopped and carried out at normal conditions.

WORK MEASUREMENTSynthetic or synthesised time Synthesised time standards are built up with

individual element times extracted from time study records.

In this way the labour content of new operations can be estimated beforehand.

This is by utilising similar elements taken from the past experiences.

WORK MEASUREMENTAnalytical estimating This method is used to assess time standard for

non-repetitive work. It is when work measurement by time study

would be too expensive. Including in some circumstances when it is

impossible to consider time study. To be able to collect accurate information the

estimators must be experienced in work study and time study.

WORK MEASUREMENT They should use synthetic times when ever is

needed.

In this method the observer uses personalexperience by:1. by analysing individual elements of a task2. by allowing estimated performance time with

rest allowances to be included in that study

WORK STUDYSampling  A complete investigation of a statistical problem

would be expensive. Therefore it is usual to study a percentage of the

event and apply the result to the whole field of investigation.

The sampling can be accepted based on:

WORK STUDYThe law of statistical regularity asserts that: a small sample of items chosen at random from

large group will tend to possess the same characteristic s as the larger group.

The law of inertia of large numbers states that movements of the separate parts of an aggregate will tend to compensate on another.

and that consequently larger aggregates are relatively more stable than small ones.

WORK STUDYActivity sampling This is a useful method for site supervision and

site planning. This can be carried out by making statistical

analysis of random sample observations. Techniques-Field activity count Two mechanical counters are used to take the

count.

WORK STUDY These counters are held in each hand. On one counter all the operators (active) are

recorded. On the other all the inactive operators are

recorded. This method does not include the sub-

contractors. The counting takes place twice a day at random

by varying routes.

WORK STUDY The total number of operatives should be

between 75-80 % of total. Therefore activity rating= No of observed

active x100/ Total no. ObservedRandom observation studies Once the non-productive operatives or machinery

is established on site the management most decide on carrying out production study.

The production study will establish; the amount of idle time (in effective time)

WORK STUDY analysing the idle time (in effective time) analysing the productive time (effective time) rating the productive(effective) time

Ineffective time= (No of productiveobservation x100) / Total no. of observation