Relationship between HVAC airflow rates and noise levels, and noise control in a mechanically-ventilated university building.(heating, ventilation and ... An article from: ASHRAE Transactions
Book Details
Author(s)Murray Hodgson
ISBN / ASINB003QN3ZVY
ISBN-13978B003QN3ZV0
AvailabilityAvailable for download now
MarketplaceUnited States 🇺🇸
Description
This digital document is an article from ASHRAE Transactions, published by American Society of Heating, Refrigerating, and Air-Conditioning Engineers, Inc. on January 1, 2010. The length of the article is 4125 words. The page length shown above is based on a typical 300-word page. The article is delivered in HTML format and is available immediately after purchase. You can view it with any web browser.
From the author: An investigation was conducted into HVAC-related airflow rates and noise levels in five classrooms in a mechanically-ventilated building at the University of British Columbia (UBC), the relationship between them, and how to control the noise. Sound-pressure levels were measured in terms of total, A-weighted level, Noise Criteria (NC) and Room Criteria (RC) ratings, and the results compared with established acceptability criteria. Airflow velocities were measured at each ventilation outlet in each classroom and corresponding volume airflow rates determined. The volume airflow data were compared with UBC design standards and specifications in previous balancing records. Comparison of the measured volume airflow rates and noise revealed a direct relationship between the two factors. Classrooms meeting the minimum airflow requirements tended to be excessively noisy. Classrooms with acceptable noise levels tended to have inadequate volume airflow rates. The main source of noise was excessive turbulence over dampers and diffusers, intensified by poor damper placement and high airflow velocities. To make noise levels acceptable, three of the classrooms could have their ventilation systems balanced to lower volume airflow rates to the applicable minimum standard. In addition, face dampers could be replaced by volume extractors; branch takeoffs could be lengthened and their ducts enlarged. Two of the classrooms could have their volume airflow rates increased to comply with the ventilation standards. The results suggest that achieving both acceptable ventilation and noise quality in mechanically-ventilated buildings can be a challenge; they also confirm that environmental factors are not independent, and must be optimized from a multi-disciplinary perspective if high-quality environments are to be achieved for building occupants.
Citation Details
Title: Relationship between HVAC airflow rates and noise levels, and noise control in a mechanically-ventilated university building.(heating, ventilation and air-conditioning system)(Report)
Author: Murray Hodgson
Publication:ASHRAE Transactions (Magazine/Journal)
Date: January 1, 2010
Publisher: American Society of Heating, Refrigerating, and Air-Conditioning Engineers, Inc.
Volume: 116 Issue: 1 Page: 550(6)
Article Type: Report
Distributed by Gale, a part of Cengage Learning
From the author: An investigation was conducted into HVAC-related airflow rates and noise levels in five classrooms in a mechanically-ventilated building at the University of British Columbia (UBC), the relationship between them, and how to control the noise. Sound-pressure levels were measured in terms of total, A-weighted level, Noise Criteria (NC) and Room Criteria (RC) ratings, and the results compared with established acceptability criteria. Airflow velocities were measured at each ventilation outlet in each classroom and corresponding volume airflow rates determined. The volume airflow data were compared with UBC design standards and specifications in previous balancing records. Comparison of the measured volume airflow rates and noise revealed a direct relationship between the two factors. Classrooms meeting the minimum airflow requirements tended to be excessively noisy. Classrooms with acceptable noise levels tended to have inadequate volume airflow rates. The main source of noise was excessive turbulence over dampers and diffusers, intensified by poor damper placement and high airflow velocities. To make noise levels acceptable, three of the classrooms could have their ventilation systems balanced to lower volume airflow rates to the applicable minimum standard. In addition, face dampers could be replaced by volume extractors; branch takeoffs could be lengthened and their ducts enlarged. Two of the classrooms could have their volume airflow rates increased to comply with the ventilation standards. The results suggest that achieving both acceptable ventilation and noise quality in mechanically-ventilated buildings can be a challenge; they also confirm that environmental factors are not independent, and must be optimized from a multi-disciplinary perspective if high-quality environments are to be achieved for building occupants.
Citation Details
Title: Relationship between HVAC airflow rates and noise levels, and noise control in a mechanically-ventilated university building.(heating, ventilation and air-conditioning system)(Report)
Author: Murray Hodgson
Publication:ASHRAE Transactions (Magazine/Journal)
Date: January 1, 2010
Publisher: American Society of Heating, Refrigerating, and Air-Conditioning Engineers, Inc.
Volume: 116 Issue: 1 Page: 550(6)
Article Type: Report
Distributed by Gale, a part of Cengage Learning
