Mr. Thalheimer has performed several interior architectural acoustics projects to assess hearing conservation and comfort for employees and the suitability of performing arts venues for patron enjoyment. This type of work often includes performing spectral background noise measurements and reverberation time measurements from which most acoustical parameters can be deduced. Appropriate noise criteria are suggested and interior acoustical treatments are recommended to achieve the desired goals.
Example projects in which Mr. Thalheimer evaluated interior acoustical conditions include the following:
- LaGuardia Airport Air Traffic Control Tower, Skanska/Walsh JV, New York, NY (2016) – Performed a special study at the request of the Federal Aviation Administration (FAA) to assess potentially dangerous communication interruptions for air traffic controllers caused by construction near the tower. Performed an hour of simultaneous noise measurements inside and outside the control tower to establish control tower facade’s noise reduction properties. Predicted construction noise from pile driving, vac-truck excavators and hoe rams to the exterior of the tower using the Cadna-A model, and then used the measured noise reduction to predict interior noise conditions. Evaluated potential for speech interference using the Articulation Index from ANSI S3.5. Determined that both male and female control operators could maintain good speech intelligibility (i.e. AI>=0.8) speaking in a loud tone of voice. Control operators would not need to shout to be understood.
- Chicago Hancock Tower Interior Noise Control, 175 East Delaware Place Homeowners Association, Chicago, IL – Hired by residents association to provide guidance and recommendations to improve intra-unit noise control and privacy of luxury condominiums in the Chicago Hancock Tower. Provided acoustical tutorial, researched relevant interior noise guidelines and standards, estimated STC and IIC of existing wall and floor/ceiling construction, and developed a Building Interior Construction Noise Specification to manage future new construction and renovation noise. Thal-Asc.
- Residential Invasive Sound Study, Francis/Gates Residence, Waltham, MA – Performed a residential sound study for a hard of hearing couple to measure and evaluate low frequency music and other noise being produced by upstairs neighbors. Collected long-term unattended noise data and recording, had residents log time and description of objectionable noise events, researched relevant indoor noise criteria, and presented results showing excessive impacts of the Waltham Noise Code. Thal-Asc.
- Condominium Rooftop Ventilation Fan Noise Control, Greater Boston Properties, Boston, MA – Performed a noise and vibration analysis of a restaurant ventilation fan located on a condominium rooftop at 533 Columbus Avenue. The fan was generating significant low frequency noise inside the building and giving residents headaches and nausea. Interior noise measurements were evaluated against recommended dBA, NC and RC criteria, and vibration measurements on the fan and building were evaluated for possibly causing structural damages. It was concluded that the low frequency noise problem was due to structure-borne noise so the vibrating rooftop fan was mitigated by relocating it onto the building’s structural members, making better use of vibration isolator springs, installing a variable speed drive, and most importantly, rebalancing the fan. The results revealed a remarkable reduction virtually eliminating the interior low frequency noise problem. Thal-Asc.
- Rooftop HVAC Units Noise and Vibration Control, Johnson Controls, Wareham and Canton, MA (2012) - Performed noise and vibration assessment for two buildings in which interior noise conditions were considered unacceptable due to the presence of multiple rooftop mounted HVAC units. Performed existing conditions noise and vibration measurements and recommended means of reducing noise and vibration via vibration isolation curbs, improved air duct positions and vanes, duct lagging enclosures, and roof enhancement. The results inside affected top floor conference rooms were evaluated using NC criteria per ANSI Standard S12.2 and RC criteria per ASHRAE guidelines.
- Windsor Locks Readiness Center, US National Guard, Windsor Locks, CT (2012) - Performed all acoustical services in support on the design of a new National Guard Readiness Center located at Bradley International Airport. Performed ambient and specific source noise measurements in order to recommended suitable exterior building facade and windows. Particularly loud noise sources to accommodate included Blackhawk (UH-60) and Chinook (CH-47) helicopters. Reviewed contractor submittals to ensure interior doors and partitions were in compliance with project specifications.
- Camp Lejeune, US Marine Corps, NC (2011) – Performed reverberation time calculations and evaluation of newly construction Applied Instruction Facility lecture/training center at Camp Lejeune, advised construction managers of acoustical criteria and required performance specifications, successfully recommended a more appropriate reverberation time requirement of 1 second in 500 Hz octave band for the lecture hall which will seat 450 marines, provided recommendations for additional acoustical absorption if space requires.
- MathWorks Campus Expansion, Rizzo TetraTech/Spagnolo Giness & Associates, Natick, MA – Performed a traffic noise analysis as well as an analysis of potential mechanical/ventilation noise associated with the expansion of the MathWorks headquarters facility in Natick, MA. The analyses focused on a controversial open-walled parking garage. Ambient noise measurements were performed and future noise levels were predicted using the FHWA TNM model for traffic noise, the FHWA RCNM model for construction noise, and custom empirical/analytical models for mechanical/ventilation noise in accordance with Mass DEP Policy 90-001 (310 CRM 7.10). The results were presented before the Natick Planning Board. Additional work was provided to reconfirm noise compliance in the community from the rooftop HVAC units on the building at Apple Hill 4 using the Cadna-A model. Noise from rooftop and penthouse HVAC equipment was also analyzed using the TAP model to ensure that upper floor conference rooms would have acceptable interior noise conditions. Thal-Asc.
- Cloonan School Auditorium Acoustics Evaluation, Stamford, CT – Performed reverberation time measurements inside the auditorium of the Cloonan Middle School prior to the auditorium being renovated. Evaluated proposed replacement acoustical absorption materials to ensure that the renovated auditorium will have similarly desirable acoustical conditions. Thal-Asc.
- National Guard Armory Building, Natick, MA (2000) - Performed an interior acoustics assessment of a large reverberant armory building (230,000 cu.ft.) which is planned to be used for functions associated with the Town of Natick's 350th Anniversary. Reverberation time models using Sabin's methods were developed to simulate the space's existing acoustic properties, and options for various additional sound absorptive treatments were evaluated. Recommendations for treatments and costs were developed and presented to Town organizers with the goal of achieving a more appropriate acoustic environment for the intended functions. Thal-Asc.
- Notch Welding & Contracting Noise Survey, Chicopee, MA (1991) - Performed occupational noise survey for MEIE insurance and employee safety purposes. Noise measurements led to recommendations for controlling excessive metal shop-related activity noise. Atlantic Applied Research.
- NECCO Candy Factory Reverberation Tests, Cambridge, MA (1990) - Performed candy factory interior reverberation tests using an automated reverberation time noise analyzer (B&K 2231) in order to advise noise absorption treatments. Bolt Beranek & Newman, Acentech.
- Boston Museum of Science, Boston, MA (1982) - Performed ambient noise study in an effort to improve interior acoustic conditions. Cavanaugh Tocci Associates.
- Office Building, Marlboro, MA (1982) - Performed interior octave band spectral
measurements to determine interior NC ratings. Cavanaugh Tocci Associates.