Industrial Noise Series
The following documents provide an overview of environmental, industrial and workplace sound and noise control, including baffle and silencer design.
Fundamentals of Environmental Sound
Author
Elden F. Ray
Synopsis
The Fundamentals of Environmental Sound explains the basics of noise, including the audible spectrum and sound waves. It describes how sound is measured, including decibels, frequency and weighted sound levels, and the basics of silencers and noise control products.
Table of contents:
- Sound Metrics
- The Basics of Noise Control
Audible spectrum.
Community and Environmental Noise
Author
Elden F.Ray
Synopsis
Community and Environmental Noise covers the acceptability of noise in a community, provides an overview of sound level measurements used by regulatory agencies, describes the physical and psychological affect of noise on humans, and defines environmental sound descriptors.
Table of contents:
- Environmental Noise
- Community Reaction
- Day-Night Sound Level
- Tones and Infra-Sound
- Regulatory Sound Levels
- Environmental Sound Descriptors
Histogram of power plant sound levels.
Near-Field Noise
Author
Elden F.Ray
Synopsis
Near-Field Noise defines near-field sound level and breakout noise and outlines the criteria and pitfalls that must be taken into consideration when designing silencing solutions for customers.
Table of contents:
- Near Field Sound Level
- Where is the Criterion?
- Where and What is the Source of the Noise?
Inlet, Exhaust or vent silencer arrangement showing criterion locations. The connecting ducts or pipes on either side of the silencer can be very long.
Modeling Sound Propagation
Author
Elden F. Ray
Synopsis
Modeling Sound Propagation examines the sound modeling that is typically performed for most industrial noise applications. This section of the Industrial Noise series focuses on two aspects of sound radiation: aerodynamic sources and structural radiation from surfaces (breakout noise).
Table of contents:
- Sound Propagation
- Sound Fields
- Propagation Modeling of Sound
- Modeling Sound Propagation
Definition of sound fields.
Room Acoustics and Noise Control
Author
Elden F. Ray
Synopsis
Room Acoustics and Noise Control describes the acoustics of an interior space and the transmission of noise from one space to another space, and demonstrates how room acoustics, room sound level and material absorption are calculated for the purpose of designing noise control solutions.
Table of contents:
- Introduction
- Room Acoustics
- Material Sound Absorption
- Noise Control
Fundamentals of Noise Control
Author
Elden F. Ray
Synopsis
Fundamentals of Noise Control presents methods for modeling and determining the necessary noise reduction to meet a criterion, design issues to consider when designing a noise control solution for a particular situation.
Table of contents:
- Noise Path Modeling
- Noise Reduction and Criteria
- Sound from Openings
- Sound from Structures
- Transmission Loss
- Noise Mitigation
Absorptive Silencer Design
Author
Elden F. Ray
Synopsis
Absorptive Silencer Design explains the basics of absorptive silencer design and the fundamental approach in the design of parallel baffle silencers.
Table of contents:
- Introduction
- Silencer Performance
- Flow Resistance and Resistivity
- Flow Velocity
- Baffle Attenuation Example
- Baffle Modeling and Analysis
- Self Noise and Insertion Loss
- Insertion Loss
- Transmission Loss
- Parametric Examples
Normal attenuation versus frequency for parallel baffles.
Reactive Silencers
Author
Elden F. Ray
Synopsis
Reactive Silencers describes the challenges and needed measurements to successfully design a noise control solution for reciprocating engines.
Table of contents:
- Introduction
- Standard Silencers
- Design Basics
Analysis of a 3 Chamber Reactive Silencer
OSHA – Noise Exposure in the Workplace
Author
Elden F. Ray
Synopsis
OSHA – Noise Exposure in the Workplace provides an overview of United States regulations and regulatory agencies that govern employee exposure to high sound levels.
Table of contents:
- OSHA
- MSHA