Web viewacoustical analysis. of. the . foundry workshop. building, school. of engineering. and engineering. technology (seet), federal. university of technology akure, ondo state

ACOUSTICAL ANALYSISOF

THE FOUNDRY WORKSHOP BUILDING,

SCHOOL OF ENGINEERING AND ENGINEERING

TECHNOLOGY (SEET),

FEDERAL UNIVERSITY OF TECHNOLOGY AKURE,

ONDO STATE.

CARRIED OUT

BY

OLAJIDE FUNMINIYI DEZICK

ARC/09/7411

OKUNJOLU OLUWABUNMI ELIZABETH

ARC/09/7409

TO BE SUBMITTED TO THE DEPARTMENT OF ARCHITECTURE

IN PARTIAL FULFILMENT OF THE COURSE ENVIROMNMENTAL CONTROL III

(ACOUSTIC AND NOISE CONTROL)

(ARC 507)

DATE: JUNE, 2014 LECTURER: PROF O. OGUNSOTE

TABLE OF CONTENT

1.0 INTRODUCTION

2.0 GENERAL DESCRIPTION OF THE BUILDING COMPONENTS FINISHES.

2.1THE FLOOR FINISHES

2.2 THE WALL FINISHES

2.3 THE CEILING FINISHES

3.0 ANALYSIS OF SOURCES OF NOISE

3.1 EXTERNAL SOURCE

3.2 THE INTERNAL SOURCE

4.0 PROPOSED WAY(S) OF IMPROVING THE ACOUSTIC OF THE FOUNDRY

WORKSHOP.

4.1 INTERNAL NOISE

4.2 EXTERNAL NOISE

5.0 CONCLUSION

6.0 REFERENCES

1.0 INTRODUCTION

Acoustics is the science of sound. It is primarily aimed at enhancing speech intelligibility and

music clarity in an enclosed space.

Noise is one of the most common health hazards found in the workplace. Exposure to too

much noise can cause noise induced hearing loss, which has been the most prevalent

occupational disease for the past decades. Many countries have introduced legal obligations and

guidelines requiring employers to protect their employees and others from exposure to excessive

noise. These legal aspects set up the desired steps of a comprehensive prevention management

system to achieve reduction in risk due to exposure to noise. This stand by several employers

shows how imperative it is to know the acoustical state of any industrial workplace, therefore

this paper has been prepared to assess and analyze the acoustical state of the foundry workshop,

school of engineering and engineering technology, federal university of technology akure,ondo

state.

2.0 GENERAL DESCRIPTION OF THE WORKSHOP.

The workshop is rectangular in form. It is a single and free standing building with no

adjoining building or facility connected to it. It is located at oba nla part of FUTA ,near the

school library , engineering workshop and the academic building. The premise of the building is

partially surrounded by shrubs and trees.

It possesses a special foundation (probably because of the potential vibration resulting

from machines which the foundation will be subjected to).At the corners of the walls, instead of

the usual reinforcement concrete column, used was a stanchioned steel bar connected to the

foundation .The walls are made of hollow sandcrete block. The windows are small

(600mm*600mm wide), the windows are glass louver blade windows and raised to a

considerable height. It has three doors, the biggest serving as the main entrance while the

remaining two serves as the exit doors, these doors are all made of steel. The roof of the building

is made of steel as the roof trusses while the roofing sheet is made of long span aluminum

roofing sheets.

Location map of the foundry workshop

Floor plan of the foundry workshop.

Approach elevation. Left-side elevation.

Rear elevation right-side elevation

2.1THE FLOOR FINISHES

The floor of the building is left unfinished. Floor screed is the only floor material

that was used. This floor screed, generates lesser noise compare to when finishes like

terrazzo are used.

Picture showing floor left bare, with the floor screed as the finishing.

2.2 THE WALL FINISHES

Wall surfaces affect the level at which sound is absorbed, transmitted and reflected. The

walls are made of sandcrete hollow block and finished with emulsion paint.

Picture showing interior walls finished with emulsion paint.

2.3 THE CEILING FINISHES

There is no ceiling used, rather the roofing sheet and trusses serves as the ceiling.

More so the roof is constructed in a manner that will help to trap the noise being

generated by the workshop. With the roof serving as the ceiling, reflection of sounds in

the workshop has actually indirectly been enhanced through the design, which is not good

enough. The steel trusses are prone to generating noise when subjected to vibration they

should not have been exposed, acoustic materials could have been used to cover the

trusses to reduce the level of reflection of sound.

Picture showing the interior of the workshop with no ceiling.

3.0 ANALYSIS OF SOURCES OF NOISE

The acoustic condition of the workshop is affected by various factors which range

from external to internal factors i.e. noise is generated from both external and internal sources.

3.1 EXTERNAL SOURCE

External sources of noise include:

i. Noise generated from the car park which is located close to the workshop.

Picture showing parking spaces located at the front of the workshop which is a source of external

noise generation.

ii. Traffic from the adjoining

road coming from the other part of the school also contributes as source of

external noise.

iii. Noises are also generated from adjoining buildings e.g. the academic building

located close to the workshop.

Analysis of external noise

3.2 THE INTERNAL SOURCE

Major internal noise in the workshop arises from the machines and the handy tools during

use.

Noise generating machines includes;

i. Generating plant: this is the alternative source of energy when there is no

power supply from the power supply authority. It generates the highest level

of noise in the workshop of about 70dB.the plant is placed in the workshop

which makes its adverse effect more manifested.

Picture showing the generating plant

ii. Pressure furnace: these are two in number, the first being the compression

pressure furnace-which uses diesel for its fire supply- and the second is the

gas pressure furnaces which produces fire for heating of moldings by gas

pumping with pressure to ensure continuous supply of the fire. They both

generate noise during operation by the fire, whenever it is burning ,which is

usually with pressure. The noise generated by this furnace is around 40dB.

Compression pressure furnace.

Gas pressure furnace.

iii. Rotary furnace: This is the biggest of all the furnaces in the workshop. As a

result, it generates more noise than the other furnaces. Its purpose like the

other aforementioned ones is to produce an uninterrupted supply of fire for

heating. During the process of fire supply or heating, a handful amount of

noise around 56dB is generated.

Rotary furnace.

Other noise generating machines includes;

Polymer extractor

Grinding machines

Other noises are generated by hand-held tools like; hammers (generates noise during

hammering), hacksaws (noise generated during cutting) and files (generates noise during filing)

Hammering. Cutting and filing.

3.0 PROPOSED WAY(S) OF IMPROVING THE ACOUSTIC OF THE FOUNDRY

WORKSHOP.

4.1 INTERNAL NOISE

The foundry workshop is an existing work place. Therefore noise control

method of an existing workplace is best to be applied. The best method is

hierarchy of control.

The hierarchy of control can be divided into:

Elimination:

Substitution

Isolation

Engineering control at source and in the transmission path.

Noise is a by-product produced during a transfer of energy, when some of the energy is not

directly converted into useful work or into waste heat. The ways to control noise are:

reduce the amount of sound energy released;

divert the flow of the energy away from the receiver; or

Protect the receiver from this energy.

Elimination

Elimination is the first step that is usually considered when addressing exposure to noise at a

workplace. After a critical examination of all existing processes it may be possible to eliminate

the exposure entirely by changing one or more operations. For example, high quality welding

eliminates or significantly reduces the need for grinding.

Substitution

This involves substituting quieter processes for noisy ones. A properly designed purchasing

policy that incorporates the "buy quiet" concept is often the best and most cost-effective way of

controlling noise exposure. It also minimizes the need for noise control later, which often can be

very costly. A decision on the maximum acceptable noise emission levels from new equipment

should be made before purchasing. This decision should take into account the organization’s

noise policy and the existing noise levels in the area where equipment is to be placed.

Isolation

Isolation means separating noise sources from people involved in the work or others standing

nearby. It could mean relocating the noise source or relocating the operators or others to

positions away from the noise source. For example, by doubling the distance from the source

inside a workshop the noise level decreases by about 2-4 dB (A), or in the open the noise level

decreases by 6 dB (A).in the foundry workshop for example, the generating plant is installed

inside the workshop. In cases like this the noise in the workshop can be reduced significantly by

housing the plant outside the workshop.

Other methods include;

Administrative control is another method of noise control that as proved to be effective with

little or no cost implications. It is any arrangement that significantly reduces the worker's

exposure time to noise hazards, for example, job rotation, production scheduling, job redesign

and introducing appropriate training on noise.

Provision of personal protective equipment: this involves the use of protective equipments

such as earplugs or earmuffs. It is usually treated as the last line of defence against noise when

noise and administrative control measures are unable to keep the noise levels below the criteria

set for the workplace.

4.2 EXTERNAL NOISE

External noise of the foundry workshop can be reduced by;

i. Screening: this can be done by planting or installing trees, hedges and other

barriers between the workshop and adjoining roads. These barrier(s) will then

reflect any ensuing noise as a result of traffic.

ii. Insulation: this involves the use and application of insulating materials on

external walls so as to reduce the transmission through the walls into the

workshop

5.0 CONCLUSION

Every employee, student or researcher desires to have a good long lasting life and with all parts

of their body (especially Ears) functioning well. Therefore, it becomes imperative to create or

ensure a healthy environment for students, researchers and lecturers who work at or carry out

experiment out at the foundry workshop.

Exposure to too much noise by anybody can lead to temporary or permanent hearing loss.

So, analyzing acoustic situation of any building (especially workshops) becomes crucial. As an

architect, acoustic of any facility should be considered important and monitored during design

stages. Also clients should be advised by architect on the need and benefits of acoustic analysis

of new and existing workplace since this can help boost the productivity of the workers.

6.0 REFERENCES

Professor Olu OlaOgunsote. Acoustics and Noise Control Lecture notes Gary W Seiben, Martin A. Gold, Glenn W Seiben, Michael G. Ermann. (2000); Language Speech and Hearing Services in Schools. Vol.31. pp 376-384 Ivor H. Seeley,(1974); Building Technology, sound insulation pp 276. www.sdngnet.com