Using the Absorptive-Dissipative Silencer in Air Conditioning Systems of an Office Environment in Order to Provide Acoustic Comfort
Air conditioning systems are the main source of background low frequency noise in administrative buildings, restaurants, classrooms, and hotels. There are different ways to reduce the low frequency noise. Silencers are generic tools which are utilized for controlling noise produced by air conditioni...
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| Format: | Article |
| Language: | English |
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Iranian Journal of Health, Safety and Environment
2018-10-01
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| Series: | Iranian Journal of Health, Safety and Environment |
| Subjects: | |
| Online Access: | http://ijhse.ir/index.php/IJHSE/article/view/360 |
| _version_ | 1818322751321014272 |
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| author | Zahra Moradpour Sajjad Farhadi Mohsen Mohsenabadi Mahdi Jalali Ghasem Hesam |
| author_facet | Zahra Moradpour Sajjad Farhadi Mohsen Mohsenabadi Mahdi Jalali Ghasem Hesam |
| author_sort | Zahra Moradpour |
| collection | DOAJ |
| description | Air conditioning systems are the main source of background low frequency noise in administrative buildings, restaurants, classrooms, and hotels. There are different ways to reduce the low frequency noise. Silencers are generic tools which are utilized for controlling noise produced by air conditioning systems. Sound assessment and frequency analysis were performed in accordance with standard methods to evaluate the exposure of workers in separate work stations. In the next step, an absorptive- dissipative silencer which its inner side was covered by convoluted acoustical foam was implemented in the ventilation system. The exposure of employees was re-evaluated. Moreover, Preferred Noise Criterion (PNC) and Speech Interference Level (SIL) were two acoustic indices used for assessing the effectiveness of the silencer. Before implementing the silencer, the sound pressure level in the rooms was between 57.8 and 61.1dBA with a peak frequency at 125Hz. The implemented silencer with dimensions of 1.4 ×1×1m, and inlet and outlet area of 0.45×0.45m was able to reduce the sound pressure level of about 13 to 14.2dB. Further, the PNC and the SIL indices were reduced to 14.33 and 15.31dB, respectively. The implemented absorptive- dissipative silencer reduced the sound pressure level of about 13.6dBA. Moreover, PNC and SIL indices are two important indices which can be used for assessing the level of comfort in office buildings. |
| first_indexed | 2024-12-13T11:01:46Z |
| format | Article |
| id | doaj.art-7d21bdd6258c4063a7f733c93cccf67c |
| institution | Directory Open Access Journal |
| issn | 2345-3206 2345-5535 |
| language | English |
| last_indexed | 2024-12-13T11:01:46Z |
| publishDate | 2018-10-01 |
| publisher | Iranian Journal of Health, Safety and Environment |
| record_format | Article |
| series | Iranian Journal of Health, Safety and Environment |
| spelling | doaj.art-7d21bdd6258c4063a7f733c93cccf67c2022-12-21T23:49:14ZengIranian Journal of Health, Safety and EnvironmentIranian Journal of Health, Safety and Environment2345-32062345-55352018-10-015411381143168Using the Absorptive-Dissipative Silencer in Air Conditioning Systems of an Office Environment in Order to Provide Acoustic ComfortZahra Moradpour0Sajjad Farhadi1Mohsen Mohsenabadi2Mahdi Jalali3Ghasem Hesam4Department of Occupational Health Engineering, Occupational and Environmental Health Research Center, School of Public Health, Shahroud University of Medical Sciences, Shahroud, Iran.Center of Excellence for Occupational Health, Research Center for Health sciences, School of Public Health, Hamadan University of Medical Sciences, Hamadan, Iran.Department of Ergonomics, School of Public Health, Mazandaran University of Medical Sciences, Mazandaran, Iran.Department of Occupational Health Engineering, School of Public Health, Neyshabur University of Medical Sciences, Neyshabur, Iran.Department of Occupational Health Engineering, Occupational and Environmental Health Research Center, School of Public Health, Shahroud University of Medical Sciences, Shahroud, Iran.Air conditioning systems are the main source of background low frequency noise in administrative buildings, restaurants, classrooms, and hotels. There are different ways to reduce the low frequency noise. Silencers are generic tools which are utilized for controlling noise produced by air conditioning systems. Sound assessment and frequency analysis were performed in accordance with standard methods to evaluate the exposure of workers in separate work stations. In the next step, an absorptive- dissipative silencer which its inner side was covered by convoluted acoustical foam was implemented in the ventilation system. The exposure of employees was re-evaluated. Moreover, Preferred Noise Criterion (PNC) and Speech Interference Level (SIL) were two acoustic indices used for assessing the effectiveness of the silencer. Before implementing the silencer, the sound pressure level in the rooms was between 57.8 and 61.1dBA with a peak frequency at 125Hz. The implemented silencer with dimensions of 1.4 ×1×1m, and inlet and outlet area of 0.45×0.45m was able to reduce the sound pressure level of about 13 to 14.2dB. Further, the PNC and the SIL indices were reduced to 14.33 and 15.31dB, respectively. The implemented absorptive- dissipative silencer reduced the sound pressure level of about 13.6dBA. Moreover, PNC and SIL indices are two important indices which can be used for assessing the level of comfort in office buildings.http://ijhse.ir/index.php/IJHSE/article/view/360Noise Pollution, Silencer, Air Conditioning System, Acoustic Comfort |
| spellingShingle | Zahra Moradpour Sajjad Farhadi Mohsen Mohsenabadi Mahdi Jalali Ghasem Hesam Using the Absorptive-Dissipative Silencer in Air Conditioning Systems of an Office Environment in Order to Provide Acoustic Comfort Iranian Journal of Health, Safety and Environment Noise Pollution, Silencer, Air Conditioning System, Acoustic Comfort |
| title | Using the Absorptive-Dissipative Silencer in Air Conditioning Systems of an Office Environment in Order to Provide Acoustic Comfort |
| title_full | Using the Absorptive-Dissipative Silencer in Air Conditioning Systems of an Office Environment in Order to Provide Acoustic Comfort |
| title_fullStr | Using the Absorptive-Dissipative Silencer in Air Conditioning Systems of an Office Environment in Order to Provide Acoustic Comfort |
| title_full_unstemmed | Using the Absorptive-Dissipative Silencer in Air Conditioning Systems of an Office Environment in Order to Provide Acoustic Comfort |
| title_short | Using the Absorptive-Dissipative Silencer in Air Conditioning Systems of an Office Environment in Order to Provide Acoustic Comfort |
| title_sort | using the absorptive dissipative silencer in air conditioning systems of an office environment in order to provide acoustic comfort |
| topic | Noise Pollution, Silencer, Air Conditioning System, Acoustic Comfort |
| url | http://ijhse.ir/index.php/IJHSE/article/view/360 |
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