Noise is a concern in most industrial settings, and noise control requires attention to a multitude of sources and receivers. All facilities include human occupants who need safe and productive environments. Workplace noise limits set by OSHA and other regulatory agencies are intended to protect workers against undue exposure to loud sounds.
Acoustical Design & Measurement
Industrial & OSHA noise control
Residential / Commercial / Office Noise
Residential: Interior noise influences quality of life for occupants and can degrade property values for owners and developers. Intrusive noise from neighboring units can disturb residents and lead to legal confrontations that could be avoided with proper design. Our goal is to meet owner’s and tenants’ expectations with manageable risk and minimized construction cost. We can design to prevent intrusive noise in residential spaces, test existing residential units to check how they comply with their design and municipal codes, and model mitigation measures to ameliorate noise complaints. Our experience spans all market segments, from affordable to market rate to luxury.
Commercial / Office: Acoustical design of commercial buildings is usually driven by human sensitivities. The goal is to deliver healthy and productive work environments, from outdoor gathering spaces to private offices to telepresence suites. In addition to routine architectural acoustics and mechanical noise control design, we can assist with construction noise mitigation and monitoring.
Community & Environmental Noise
Community and environmental noise issues arise in response to conflicting uses and goals in society. Transportation infrastructure, dense urban residential housing, and the mechanical systems needs of commercial and industrial facilities pose potential challenges. From human safety and comfort to extremely demanding high-tech laboratory and research needs, environmental noise can be viewed as a pollutant that must be recognized and controlled. Our work also includes researching and writing EIR’s and creating legal documentation for CEQA / NEPA, to meet environmental and community requirements.
Ultra Low-noise Design For Lab, Nanotech, Imaging
Nanotechnology, semiconductor fabrication and imaging facilities require an ultra-low noise and ultra-low vibration environment, otherwise research accuracy or production yield suffers. Noise can intrude from exterior vehicle or rail traffic, from internal occupants and research equipment, or from the large machinery and delivery systems required to support these facilities. Given the high stakes, these are some of our most challenging projects, calling on the following skills:
- Mechanical Systems noise control design & specification
- Acoustical Design for human, lab animal, and instrument performance
- Retrofit Design to support new processes and update toolsets
- Test and Measurement site surveys, performance validation, benchmarking
- Wireless Monitoring of construction impact on existing facilities & surrounding community
- Environmental Impact planning and noise mitigation strategies
Noise Measurement & Testing
Transportation infrastructure, dense urban settings and the mechanical systems of commercial and industrial facilities can generate significant ambient noise levels impinging on a target design space. The first step in a new design is often a careful measurement of the interior and/or exterior baseline noise environment. Alternately, an existing design might be measured to diagnose noise complaints or confirm compliance with noise regulations. We have extensive experience making a wide variety of noise measurements (STC, IIC, NC, reverberation time, etc.) in all kinds of spaces.
Vibration Design & Measurement
Machinery & HVAC Vibration Control
Machinery and air-handling systems can have many rotating components capable of transmitting vibration to the structure and on to senstive receivers in the space. Plumbing systems can also be the source of structural vibration due to fluid flow. These vibration problems can require a careful analysis of vibration sources and paths. Once these are identified, the solution can be various vibration isolators or mitigation systems.
Building Structural Vibration Design
Building design for low- or ultra-low vibration requires careful consideration of building materials and the coupling between building components including floors, walls and support columns. With a new building design, we model the building’s vibration characteristics using finite element techniques, in order to predict vibration levels at locations throughout the structure. We then compare this to the vibration requirements of the tools or instruments to be used inside it. If the criteria are not met, we modify the structure in our computer model, in order to adjust the structural dynamics to meet the required vibration levels.
Post-construction Design Revision
Two reasons for building design revision are repurposing a structure for a new use and correcting some aspect of new construction that fails to meet the design spec or the needs of the occupant. For example, we have redesigned structures to convert a factory floor from low-tech CRT manufacturing to low-vibration plasma display panel production, to modify a factory floor for the ultra-low vibration requirements of SEM’s and the low-noise requirements of office and laboratory space.
Ultra Low-vibration Design for Lab, Semi Fab, Imaging
Nanotechnology, semiconductor fabrication and imaging facilities require an ultra-low noise and ultra-low vibration environment, otherwise research accuracy or production yield suffers. Some laboratories need even lower vibration environments to push commercial tools beyond their limits or develop a new instrument generation. Vibration can intrude from exterior vehicle or rail traffic, from internal occupants and research equipment, or from the large machinery and delivery systems required to support these facilities. Given the high stakes, these are some of our most challenging projects, calling on the following skills:
- Structural Dynamicsand finite element modeling for vibration of critical structures
- Mechanical Systems vibration control design & specification
- Tool Installation Supportand instrument foundation/pedestal design and testing
- Retrofit Design to support new processes and update toolsets
- Test and Measurementsite surveys, performance validation, benchmarking
- Wireless Monitoringof construction impact on existing facilities & surrounding community
- Environmental Impact planning and vibration mitigation strategies
Structural Dynamics & Finite Element Analysis
We have extensive experience constructing 3D finite element models of a structural design (including soil effect) to probe the structure’s dynamic behavior. We can perform an in-situ study of vibration sources, to extract their vibration forcing function, then perform a dynamic analysis of the building structure using FEM. Using our models, we can often find a cost effective solution for minimizing the transmission of dynamic forces between floors containing sensitive equipment and other floors in the building, and the best location for that equipment on the floor plan.
Vibration Measurement & Testing
Nanotechnology, semiconductor fabrication and imaging facilities require an ultra-low vibration environment, otherwise research accuracy or production yield suffers. The first step in a new design is often a careful measurement of the interior and/or exterior baseline vibration environment. Alternately, an existing design might be measured to diagnose noise complaints or confirm compliance with noise regulations. In a different area, real-time FFT spectrum vibration monitoring may be required to measure and regulate vibration levels due to construction activities. We have extensive experience with vibration measurements in all kinds of spaces and environments.
Noise & Vibration Monitoring
Many construction projects require careful monitoring of noise and/or vibration impacts on adjacent communities and structures, to avoid exceeding local regulations or damaging adjacent property. In addition, underwater construction activities, such as pile-driving in bridge construction, can generate extreme underwater sound levels, which are regulated to protect marine wildlife. This requires careful monitoring of underwater sound levels, to avoid exceeding regulations.
We own and maintain a full suite of noise and vibration monitoring instruments, capable of both attended and remote operation. The remote systems can be programmed to monitor noise and vibration levels continuously in real-time and issue exceedance alerts via SMS message and email. Our construction services can begin at the project planning stage: our engineering staff can develop mitigation strategies to minimize the chance of unacceptable impacts.
Audio Visual Services
VACC is excited to introduce a new service: the design, installation and maintenance of audio-visual (AV) facilities. This offering draws on our skillset in audio engineering, room acoustics, and audio-visual design.
- Customize: meet with the client to discuss AV requirements and specify an AV installation to optimize reliability and economy.
- AV design: use our AV skills to design a AV installation that is state-of-the-art in performance, connectivity, security and reliability.
- Acoustical design: for a new AV space, use our acoustical skills to design for audibility, acoustical comfort, effective communication and sound isolation for security and comfort.
- Troubleshoot & upgrade: for existing AV installations, prescribe sound treatments to improve audibility and sound isolation and troubleshoot or replace problem AV components.
- Maintenance: provide periodic maintenance on installed AV systems to maintain performance and ensure reliability.
EMI (Electromagnetic Interference)
Electromagnetic interference (EMI) is a radiated disturbance that affects an electrical circuit by electromagnetic induction or electrostatic coupling. The disturbance can result in degraded performance or even failure in the receiver circuit. In the case of a data path, effects can range from increased error rate to total data loss. In medical or mass transit applications, EMI can cause extreme damage or failure and even be life-threatening.
We have experience characterizing environmental low- and radio-frequency electromagnetic fields. We have measured the effects of EMI at client sites and we have authored EIR chapters concerning the impact of EMI radiated from client projects.
CEQA (California Environmental Quality Act)
California Environmental Quality Act (CEQA) institutes a statewide policy of environmental protection. CEQA requires state and local agencies to follow a protocol of analysis and public disclosure of environmental impacts of proposed projects and adopt all feasible measures to mitigate those impacts. CEQA makes environmental protection a mandatory part of every California state and local (public) agency’s decision making process, and has been the basis for numerous lawsuits concerning public and private projects.
Product Design & Testing
Many consumer products generate unwanted noise. Some products are too loud; some are too quiet; and others just “don’t sound right”. Sound quality is an important parameter that involves customer psychology and expectations, above and beyond basic quantitative measurements like noise level. From regulatory compliance to consumer expectations, careful noise design can make a product a commercial success, or prevent it from being rejected because of how it sounds.