Excessive noise levels are generally acknowledged to have adverse effects on our environment. Studies indicate that excessive noise levels can cause fatigue in exposed individuals, lower efficiency and productivity, impaired speech communication, and hearing loss. Excessive noise is almost everywhere today - in the office, in schools, hospitals and other institutional facilities, in all classes of public buildings, and in our factories. INDUSTRIAL NOISE High noise levels in factories can make speech communication in the plant difficult and at times impossible. Foremen are often unable to hear warning shouts from co-workers. The problem of hearing loss due to excessive noise exposure is of particular concern to industry, and to the federal government. In the early 1970s, the United States Congress passed the Occupational Safety and Health Act (OSHA) which sets criteria for health hazards and established limits for noise exposure of industrial workers. The OSHA Noise Standard was amended in 1982 to require audiometric testing of all employees exposed to noise levels of 85 dB or above for eight hours. A NOISE IN COMMERCIAL AND INSTITUTIONAL BUILDINGS While noise levels in offices, stores, schools, and other commercial and institutional buildings seldom reach those encountered in many industrial environments, they often reach levels which are distracting to the occupants of such buildings. Impairment of speech communica tion among workers, or inversely the lack of speech privacy, are both deterrents to effiCiency and productivity and are detrimental to the occupants' comfort and sense of well-being.

The second edition of Noise Control: From Concept to Application, newly expanded and thoroughly updated, now includes 180 graded problems with solutions, plus 100 end-of-chapter problems with solutions available for instructors on the authors’ website. Working from basic scientific principles, the authors show how an understanding of sound can be applied to real-world settings, working through numerous examples in detail and covering good practice in noise control for both new and existing facilities. It covers the essential topics for industrial noise control: acoustics, noise criteria, hearing-damage risk, noise-assessment measures, measurement instrumentation, sound-source types including the calculation and measurement of their output power, sound propagation outdoors, sound in rooms, sound-absorbing materials, sound transmission through partitions and enclosures, noise barriers, reactive and dissipative muffler-noise reduction and muffler-design considerations such as pressure loss and self-noise generation. Detailed explanations of important concepts make this textbook easy to understand by engineering and science undergraduates, as well as professionals with no background in acoustics. Authors’ website: www.causalsystems.com Colin H. Hansen is Emeritus Professor in Mechanical Engineering at the University of Adelaide, Australia, and past President of the International Institute of Acoustics and Vibration. Kristy L. Hansen is a Senior Lecturer in Mechanical Engineering at Flinders University, Australia, and holder of the Australian Research Council’s Discovery Early Career Researcher Award.

This book is written more for the practitioner than the casual reader. Although a high mathematical level is not needed, for much of the material some engineering knowledge is desirable. Noise control is not easy and there are no magic answers to problems. Careful study and patience are required to produce proficiency in the field of noise control.

This classic and authoritative student textbook contains information that is not over simplified and can be used to solve the real world problems encountered by noise and vibration consultants as well as the more straightforward ones handled by engineers and occupational hygienists in industry. The book covers the fundamentals of acoustics, theoretical concepts and practical application of current noise control technology. It aims to be as comprehensive as possible while still covering important concepts in sufficient detail to engender a deep understanding of the foundations upon which noise control technology is built. Topics which are extensively developed or overhauled from the fourth edition include sound propagation outdoors, amplitude modulation, hearing protection, frequency analysis, muffling devices (including 4-pole analysis and self noise), sound transmission through partitions, finite element analysis, statistical energy analysis and transportation noise. For those who are already well versed in the art and science of noise control, the book will provide an extremely useful reference. A wide range of example problems that are linked to noise control practice are available on www.causalsystems.com for free download.

This book has been written to provide an intro Chapter 2 deals with the mechanism of hear duction to the fundamental concepts of sound ing and the subjective rating of sound, includ and a comprehensive coverage whereby un ing age-related and noise-induced hearing loss. wanted sound (noise) can be controlled. Al Assessment of any noise problem involves a though there are many notable textbooks which knowledge of the instrumentation available for deal primarily with the physics (or theory) of measurements, the limitations of this instru sound, and others which treat noise control in mentation, the appropriate procedures for mak a strictly practical (and sometimes even empir ing the measurements with the instrumentation, ical) manner, there are few textbooks that pro and the methods by which the measured data vide a bridging between the necessary under can be analyzed. Chapter 3 provides an up-to standing of the fundamentals of sound (its date coverage of these requirements, including generation, propagation, measurement) and the a section on one of the newest and most valu application of these fundamentals to its control. able tools in noise studies-sound intensity This book provides that link. measurement. The capability of being able to The text presents noise control primarily at measure sound intensity as compared with con the introductory level.

By providing all the basic knowledge needed to assess how useful active noise control will be for a given problem, this book assists in the designing, setting up, and tuning of an active noise-control system. Written for students who have no prior knowledge of acoustics, signal processing, or noise control but who do have a reasonable grasp of basic physics and mathematics, the text is short and descriptive, leaving all mathematical details and proofs concerning vibrations, signal processing and the like to more advanced texts or research monographs. The book can thus be used in independent study, in a classroom with laboratories, or in conjunction with a kit for experiment or demonstration. Topics covered include basic acoustics, human perception and sound, sound intensity and related concepts, fundamentals of passive noise- control strategies, basics of digital systems and adaptive controllers, and active noise control systems.

This book treats important topics in "Acoustic Echo and Noise Control" and reports the latest developments. Methods for enhancing the quality of transmitted speech signals are gaining growing attention in universities and in industrial development laboratories. This book, written by an international team of highly qualified experts, concentrates on the modern and advanced methods.

Focusing on hydraulic components and machines rather than architectural or environmental noise control, this reference is unique in analyzing forces and moments in pumps ... showing how these forces produce noise at specific frequencies ... demonstrating how pump design controls these frequencies ... illustrating how a machine's noise-radiating surfaces affect noise ... and discussing fluid-borne noise. Noise Control of Hydraulic Machinery provides techniques for analyzing any pump type ... reviews the basics and terminology of sound, vibration, vibration isolation, fluid pulsations, Fourier analysis, cavitation, hydraulic shock, and enclosure design ... explains how pumps, motors, and valves generate airborne, structure-borne, and fluid-borne noises ... identifies hydraulic parameters that influence noise ... and guides planning programs for designing and developing quiet components or machines as well as quieting existing products. Illustrated with some 170 diagrams, Noise Control of Hydraulic Machinery is an essential reference for mechanical, fluid power, hydraulic, acoustical, and design engineers. Book jacket.