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Noise Levels of Common Construction Power Tools

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Noise Levels of Common Construction Power Tools NOISE LEVELS OF COMMON CONSTRUCTION POWER TOOLS By GREGORY CALLAHAN A THESIS PRESENTED TO THE GRADUATE SCHOOL OF THE UNIVERSITY OF FLORIDA IN PARTIAL FULFILLMENT OF THE REQUIREMENTS FOR THE DEGREE OF MASTER OF SCIENCE IN BUILDING CONSTRUCTION UNIVERSITY OF FLORIDA 2004 TABLE OF CONTENTS page LIST OF TABLES............................................................................................................. iii LIST OF FIGURES .............................................................................................................v ABSTRACT...................................................................................................................... vii CHAPTER 1 INTRODUCTION......................................................................................................1 Hearing Damage in Construction...............................................................................1 Sources of Sound........................................................................................................1 Aims and Objectives ..................................................................................................2 2 LITERATURE REVIEW...........................................................................................4 Properties of Sound ....................................................................................................4 Effects of Sound from More Than One Source..........................................................6 OSHA Regulations.....................................................................................................8 Hearing Damage.......................................................................................................11 3 RESEARCH METHODOLOGY.............................................................................13 Selection of Tools.....................................................................................................13 Measurements...........................................................................................................14 4 RESULTS.................................................................................................................24 5 CONCLUSION ........................................................................................................45 6 RECOMMENDATIONS .........................................................................................48 LIST OF REFERENCES...................................................................................................51 BIOGRAPHICAL SKETCH .............................................................................................52 ii LIST OF TABLES Table page 2-1 Scale for Combining Decibels....................................................................................7 2-2 Change in decibel levels as a function of the distance from the source.....................7 4-1 Porter Cable Circular Saw Center of Room.............................................................29 4-2 Computed Decibel Levels ........................................................................................29 4-3 Black and Decker Circular Saw Center of Room ....................................................30 4-4 Saws All Center of Room.........................................................................................31 4-5 Router Center of Room ............................................................................................31 4-6 Drill Center of Room................................................................................................32 4-7 Two Circular Saws Center of Room ........................................................................32 4-8 Miscellaneous Tools.................................................................................................33 4-9 Beltsander Center of Room......................................................................................33 4-10 Porter Cable Circular Saw Corner of Room.............................................................34 4-11 Saws All Corner of Room ........................................................................................35 4-12 Router Corner of Room............................................................................................35 4-13 Drill Corner of Room ...............................................................................................35 4-14 Two Circular Saws Corner of Room........................................................................36 4-15 Beltsander Corner of Room......................................................................................36 4-16 Porter Cable Circular Saw Against Wall Indoors ....................................................37 4-17 Drill Against Wall Indoors.......................................................................................38 4-18 Saws All Against Wall Indoors................................................................................38 iii 4-19 Beltsander Against Wall Indoors .............................................................................38 4-20 Router Against Wall Indoors....................................................................................39 4-21 Two Circular Saws Against Wall Indoors................................................................39 4-22 Porter Cable Circular Saw Open Field Measurement ..............................................40 4-23 Black and Decker Circular Saw Open Field Readings ............................................41 4-24 Two Circular Saws Open Field Readings ................................................................41 4-25 Porter Cable Circular Saw Outdoors Corner............................................................42 4-26 Two Circular Saw Outdoor Corner ..........................................................................42 4-27 Porter Cable Circular Saw Outside Against Wall ....................................................43 4-28 Two Circular Saws Outside Against Wall ...............................................................44 iv LIST OF FIGURES Figure page 2-1 Soundwave .................................................................................................................5 3-1 Sound Level Meter...................................................................................................13 3-2 Inside Center of Room Decibel Level Measurements .............................................16 3-3 Corner of Room Sound Level Measurements..........................................................17 3-4 Indoor Against Wall Sound Level Measurement.....................................................18 3-5 Open Field Sound Level Measurements ..................................................................20 3-6 Outdoor Corner Sound Level Measurement ............................................................21 3-7 Outdoor Against Wall Sound Level Measurements.................................................22 4-1 Center of Room Noise Levels ..................................................................................25 4-2 Reading Location Differences..................................................................................26 4-3 Porter Cable Circular Saw Measurements ...............................................................27 4-4 Comparison of Two Circular Saws to One Circular Saw ........................................28 v Abstract of Thesis Presented to the Graduate School of the University of Florida in Partial Fulfillment of the Requirements for the Degree of Master of Science in Building Construction NOISE LEVELS OF COMMON CONSTRUCTION POWER TOOLS By Gregory Callahan May, 2004 Chair: Jimmie Hinze Major Department: Building Construction The hearing loss of workers in the construction industry is significant. There has been research performed to measure the noise levels of equipment and tools in the construction industry, but the results of those studies are vague and unclear. The purpose of this study is to measure the noise level of numerous common power tools, with the use of sound level meter, in order to place more definite decibel levels on tools. The tools measured in the study were portable carpenter hand power tools. The tools were selected because the tools are present on almost all jobsites, regardless of the size of the project. These more definite numbers will enable employees in the construction industry to better guard against hearing loss. The goal of the study is to better understand the magnitude of the sound levels of common power tools used in the construction industry. This includes developing an understanding of the nature of sound as impacted by distance. Also the nature of sounds in different environments are explored to discover the different sound levels in numerous situations, to determine which situations place workers at greater risk. The physics of vii sound is researched and compared with the results taken to help clarify the data taken in the study. viii CHAPTER 1 INTRODUCTION Hearing Damage in Construction The loss of hearing by employees within the construction industry is significant. Over an extended period of time exposure to loud sounds that are produced on the construction site can cause hearing damage. It has been a belief within the construction industry, that construction workers, who are employed for long periods of time, over ten years, will have hearing loss. The loss of hearing is an enormous problem that many continue to ignore. “Despite the fact that it is 100 percent
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