| 1. |
- Angelova, Radostina A., et al.
(författare)
-
The response rate in postal epidemiological studies in the context of national cultural behaviour
- 2012
-
Ingår i: 10th International Conference on Healthy Buildings 2012. - 9781627480758 ; , s. 1429-1434
-
Konferensbidrag (refereegranskat)abstract
- The purpose of this study was to analyse the effect of national cultural differences on the response rate, obtained in questionnaire based epidemiological studies on allergy and asthma, performed in Sweden (DBH) and Bulgaria (ALLHOME). The two studies used one and the same methodology, but the obtained response rate was different: 78.8% in DBH and 34.5% in ALLHOME. The differences in the obtained response rate and the reasons for these differences were analyzed on the basis of the Hofstede's cultural dimensions' indexes, which clearly show the distinction in the national cultural behaviour of people in Sweden and Bulgaria. It was found that national culture could strongly influence the response behaviour of people in epidemiological studies and Hofstede's indexes can be useful tool when designing and performing epidemiological studies, and in particular - questionnaire surveys.
|
|
| 2. |
- Arghand, Taha, 1982, et al.
(författare)
-
Individually controlled localized chilled beam in conjunction with chilled ceiling: Part 1 – Physical environment
- 2016
-
Ingår i: 14th International Conference on Indoor Air Quality and Climate, Indoor Air 2016.
-
Konferensbidrag (refereegranskat)abstract
- This study investigates the indoor environment generated by localized chilled beam coupled with chilled ceiling (LCBCC) and compares it with the environment generated by mixing ventilation coupled with chilled ceiling (CCMV). The experiments were performed in a mock-up of single office (4.1 m × 4.0 m × 3.1 m, L× W× H). Thermal manikin was used to simulate room occupant. The LCBCC was placed above the workstation to improve the environment locally. Combinations of indoor temperature of 26 °C and 28 °C and ventilation airflow rate of 10 and 13 l/s were studied. The total heat load in the room was 60 W/m2 (including simulation of solar radiation and miscellaneous heat loads). The results showed that uniform thermal conditions (differences smaller than 1 °K) were generated in the occupied zone with the studied system configurations. The LCBCC diminished the effect of the buoyancy flow from the simulated window and this resulted in more acceptable thermal conditions at the workstation.
|
|
| 3. |
- Arghand, Taha, 1982, et al.
(författare)
-
Individually controlled localized chilled beam in conjunction with chilled ceiling: Part 2 – Human response
- 2016
-
Ingår i: 14th International Conference on Indoor Air Quality and Climate, Indoor Air 2016.
-
Konferensbidrag (refereegranskat)abstract
- The response of 24 subjects to the local environment established by localized chilled beam combined with chilled ceiling (LCBCC) was studied and compared with response to the environment generated by mixing ventilation combined with chilled ceiling (CCMV) at two temperature conditions of 26 °C and 28 °C. The supply airflow rate from the LCBCC was controlled by the subjects within the range of 10 to 13 L/s. In the case of CCMV subjects did not have control over the flow rate. The results showed that occupants’ overall and local thermal sensation acceptability improved at the workstation by using the LCBCC system compared to CCMV. The subjects felt less warm with the LCBCC and their thermal sensation was close to neutral. Most of the subjects achieved acceptable air movement at the workstation by the provided individual control of the flow rate from the LCBCC. Need for air movement was reported in the case of CCMV.
|
|
| 4. |
- Arghand, Taha, 1982, et al.
(författare)
-
Individually controlled localized chilled beam with background radiant cooling system: Human subject testing
- 2022
-
Ingår i: Building and Environment. - : Elsevier BV. - 0360-1323. ; 218
-
Tidskriftsartikel (refereegranskat)abstract
- This study examines the responses of twenty-four subjects to an individually-controlled localized chilled beam (LCB) and compares it to a mixing ventilation (MV) as the reference system. Both LCB and MV also used ceiling cooling (CC) panels for background cooling (forming LCBCC and MVCC systems). The LCB directed the supply air towards the subjects to create a micro-environment around them. Four experimental conditions were established using a combination of two room temperatures (26 °C and 28 °C) and two primary ventilation rates (10 l/s and 13 l/s). During the 90 min-long experiments, the subjects were asked to assess their perceived air quality, thermal sensation, comfort, air movement acceptability and acceptability of the work environment. The results indicated that the LCBCC was superior to the MVCC with significantly higher acceptability of the work environment, perceived air quality and thermal sensation. Perceived air quality and thermal sensation were rated near the “clearly acceptable” level for both room temperatures when LCBCC was used. Moreover, thermal sensation votes were close to the “neutral” level for room temperatures as high as 26 °C and 28 °C. The micro-environment established by the LCB was found to be resilient to changes in room temperature. With the MVCC, the thermal environment was rated as “slightly warm”. No major potential risk of draught among the subjects was reported when using the LCBCC. The findings of this study contribute to the development of high-temperature cooling systems in general, and localized ventilation systems in particular.
|
|
| 5. |
- Li, Angui, et al.
(författare)
-
Ventilation and environmental control of underground spaces : a short review
- 2019
-
Ingår i: E3S Web of Conferences. - : EDP Sciences.
-
Konferensbidrag (refereegranskat)abstract
- More and more underground spaces were used in 21st century because of rapid urbanization, traffic problems, etc. Underground city, metro, tunnel, mine, industrial and agriculture engineering, civil air defence engineering need large underground spaces. Underground spaces with different thermal, ventilation and lighting environments may cause comfort, health and safety problems. Concrete problems include excessive humidity, heat transfer specialty, excessive CO caused by blockage in long distance traffic tunnels, difficulty in smoke exhaust and evacuation during fire, harmful microorganism, radioactivity pollutants, psychological problems, and so forth. Air quality control technologies for underground spaces, including ventilation technology, dehumidification technology, natural energy utilization technology, smoke extraction technology and ventilation resistance reduction technology, will be reviewed. Ventilation for smoke-proof/evacuation and ventilation will also be reviewed.
|
|
| 6. |
- Morawska, Lidia, et al.
(författare)
-
COVID-19 and airborne transmission : science rejected, lives lost : can society do better?
- 2023
-
Ingår i: Clinical infectious diseases : an official publication of the Infectious Diseases Society of America. - : Oxford University Press (OUP). - 1537-6591. ; 76:10, s. 1854-1859
-
Tidskriftsartikel (refereegranskat)abstract
- This is an account that should be heard of an important struggle: the struggle of a large group of experts who came together at the beginning of the Covid-19 pandemic to warn the world about the risk of airborne transmission and the consequences of ignoring it. We alerted the World Health Organization (WHO) about the potential significance of the airborne transmission of SARS-CoV-2 and the urgent need to control it, but our concerns were dismissed. Here we describe how this happened and the consequences. We hope that by reporting this story, we can raise awareness of the importance of interdisciplinary collaboration and the need to be open to new evidence, and to prevent it from happening again. Acknowledgement of an issue and the emergence of new evidence related to it, is the first necessary step towards finding effective mitigation solutions.
|
|
| 7. |
- Morawska, Lidia, et al.
(författare)
-
How can airborne transmission of COVID-19 indoors be minimised?
- 2020
-
Ingår i: Environment International. - : Elsevier BV. - 1873-6750 .- 0160-4120. ; 142
-
Tidskriftsartikel (refereegranskat)abstract
- During the rapid rise in COVID-19 illnesses and deaths globally, and notwithstanding recommended precautions, questions are voiced about routes of transmission for this pandemic disease. Inhaling small airborne droplets is probable as a third route of infection, in addition to more widely recognized transmission via larger respiratory droplets and direct contact with infected people or contaminated surfaces. While uncertainties remain regarding the relative contributions of the different transmission pathways, we argue that existing evidence is sufficiently strong to warrant engineering controls targeting airborne transmission as part of an overall strategy to limit infection risk indoors. Appropriate building engineering controls include sufficient and effective ventilation, possibly enhanced by particle filtration and air disinfection, avoiding air recirculation and avoiding overcrowding. Often, such measures can be easily implemented and without much cost, but if only they are recognised as significant in contributing to infection control goals. We believe that the use of engineering controls in public buildings, including hospitals, shops, offices, schools, kindergartens, libraries, restaurants, cruise ships, elevators, conference rooms or public transport, in parallel with effective application of other controls (including isolation and quarantine, social distancing and hand hygiene), would be an additional important measure globally to reduce the likelihood of transmission and thereby protect healthcare workers, patients and the general public.
|
|
| 8. |
- Morawska, Lidia, et al.
(författare)
-
Mandating indoor air quality for public buildings : if some countries lead by example, standards may increasingly become normalized
- 2024
-
Ingår i: Science. - 0036-8075. ; 383:6690, s. 1418-1420
-
Tidskriftsartikel (refereegranskat)abstract
- People living in urban and industrialized societies, which are expanding globally, spend more than 90% of their time in the indoor environment, breathing indoor air (IA). Despite decades of research and advocacy, most countries do not have legislated indoor air quality (IAQ) performance standards for public spaces that address concentration levels of IA pollutants. Few building codes address operation, maintenance, and retrofitting, and most do not focus on airborne disease transmission. But the COVID-19 pandemic has made all levels of society, from community members to decision-makers, realize the importance of IAQ for human health, wellbeing, productivity, and learning. We propose that IAQ standards be mandatory for public spaces. Although enforcement of IAQ performance standards in homes is not possible, homes must be designed and equipped so that they could meet the standards.For the past two decades, scientists have called for national IAQ standards and laws to be established (2), but so far, little action has been taken. The approach to IA contrasts sharply with outdoor air, for which quality is regulated and monitored and compliance with regulations is enforced. The World Health Organization (WHO) Global Air Quality Guidelines (AQG) published in 2021 provide recommendations for concentration levels of six pollutants and their averaging times (PM2.5, PM10, NO2, SO2, CO, and O3) and apply to both outdoor air and IA (3).In cases for which IAQ standard and guideline values were established by national or association working groups, the outcomes were inconsistent; often the criteria for the same parameter differed by orders of magnitude. The reasons cited for limited progress include different criteria in the selection of the critical study, in the starting point, and in the derivation procedure; the complex political, social, and legislative situation regarding IAQ; the lack of an open, systematic, and harmonized approach; and that establishing an IAQ standard is always the result of a compromise between scientific knowledge and political will. Because of the heterogenous landscape of approaches needed, such barriers remain intact despite the considerable IAQ research and evidence base developed over the past decades.
|
|
| 9. |
|
|
| 10. |
- Sadrizadeh, Sasan, et al.
(författare)
-
A systematic review of operating room ventilation
- 2021
-
Ingår i: Journal of Building Engineering. - : Elsevier BV. - 2352-7102. ; 40, s. 102693-
-
Forskningsöversikt (refereegranskat)abstract
- Ventilation systems are the primary way of eliminating airborne pathogenic particles in an operating room (OR). However, such systems can be complex due to factors such as different surgical instruments, diverse room sizes, various staff counts, types of clothing used, different surgical types and duration, medications, and patient conditions. OR ventilation should provide a thermally comfortable environment for the surgical staff team members while preventing the patient from suffering from any extreme hypothermia. Many technical, logistical, and ethical implications need to be considered in the early stage of designing a ventilation system for an OR. Years of research and a significant number of publications have highlighted the controversy and disagreement among infection specialists, design engineers, and ventilation experts in this context. This review article aims to provide a good understanding of OR ventilation systems in the context of air quality and infection control from existing research and provide multidimensional insights for appropriate design and operation of the OR. To this end, we have conducted a systematic review of the literature, covering 253 articles in this context. Systematic review and meta-analyses were used to map the evidence and identify research gaps in the existing clinical, practical, and engineering knowledge. The present study is categorized into six research focuses: ventilation system, thermal comfort, staff work practice and obstacles, door operation and passage, air cleaning technology, emission rate, and clothing systems. In the conclusion, we summarize the key limitations of the existing studies and insights for future research direction.
|
|
| 11. |
- Su, Wei, et al.
(författare)
-
Infection probability under different air distribution patterns
- 2021
-
Ingår i: Building and Environment. - : Elsevier. - 0360-1323 .- 1873-684X. ; 207:Part B
-
Tidskriftsartikel (refereegranskat)abstract
- Infectious diseases have caused significant physical harm to humans as well as enormous economic losses over the years. Effective ventilation and distribution of fresh air could help to reduce indoor cross-infection. The computational fluid dynamics (CFD) method was used in this paper to investigate airborne transmission with seven different air distribution methods. The revised Wells-Riley model, which took into account the non-uniform air distribution generated with the methods, was used to calculate the infection probability in an office room shared by ten occupants for 4 h. One of the occupants was an infector. The significance of the infector's location was studied. The obtained infection probability was compared to that obtained in the case of complete air mixing, which is uncommon in practice. Under specified conditions of this study, personalized ventilation (PV) performed the best in terms of preventing cross-infection, followed by displacement ventilation (DV), impinging jet ventilation (IJV), stratum ventilation (SV) and wall attachment ventilation (WAV). The number of infected occupants was reduced below the number obtained under the complete mixing assumption by using these air distribution methods. Mixing ventilation (MV) and diffuse ceiling ventilation (DCV) exhibited the worst performance. In comparison to the case of complete mixing the infection probability for seven out of nine susceptible occupants was higher with MV and for all occupants in the case of DCV. In SV, the position of the infector had a clear impact on the infection probability of susceptible individuals. WAV may perform better in practice if the system is well designed. The location of the exhaust outlets had a significant impact on the infection probability for DCV.
|
|
| 12. |
- Yang, Bin, et al.
(författare)
-
Ceiling mounted personalized ventilation system in hot and humid climate-An energy analysis
- 2010
-
Ingår i: Energy and Buildings. - : Elsevier. - 0378-7788 .- 1872-6178. ; 42:12, s. 2304-2308
-
Tidskriftsartikel (refereegranskat)abstract
- This study is to evaluate energy saving potential of ceiling mounted personalized ventilation (PV) system in conjunction with background mixing ventilation compared with mixing ventilation system alone and with mixing ventilation system when occupants are provided with individually controlled desk fans for generating additional air movement at each desk. Control strategy applied includes different number of personalized ventilation air terminal devices used and different PV airflow rates supplied. Energy calculation is based on design conditions in Singapore, representing a hot and humid climate. The results reveal that increasing room temperature can save cooling energy when the combination of PV with ceiling mounted personalized ventilation nozzles and background mixing ventilation is used. In this case the energy for transport of air increases but the total energy decreases, i.e. energy can be saved due to elevated room temperature. Comparing with mixing ventilation plus desk fans, ceiling mounted personalized ventilation cannot only realize better cooling effect but also decrease the total energy consumption.
|
|
| 13. |
- Yang, Bin, et al.
(författare)
-
Ceiling mounted personalized ventilation system integrated with a secondary air distribution system-A human response study in hot and humid climate
- 2010
-
Ingår i: Indoor Air. - : John Wiley & Sons. - 0905-6947 .- 1600-0668. ; 20:4, s. 309-319
-
Tidskriftsartikel (refereegranskat)abstract
- The benefits of thermal comfort and indoor air quality with personalized ventilation (PV) systems have been demonstrated in recent studies. One of the barriers for wide spread acceptance by architects and HVAC designers has been attributed to challenges and constraints faced in the integration of PV systems with the work station. A newly developed ceiling‐mounted PV system addresses these challenges and provides a practical solution while retaining much of the apparent benefits of PV systems. Assessments of thermal environment, air movement, and air quality for ceiling‐mounted PV system were performed with tropically acclimatized subjects in a Field Environmental Chamber. Thirty‐two subjects performed normal office work and could choose to be exposed to four different PV airflow rates (4, 8, 12, and 16 L/s), thus offering themselves a reasonable degree of individual control. Ambient temperatures of 26 and 23.5°C and PV air temperatures of 26, 23.5, and 21°C were employed. The local and whole body thermal sensations were reduced when PV airflow rates were increased. Inhaled air temperature was perceived cooler and perceived air quality and air freshness improved when PV airflow rate was increased or temperature was reduced.Practical Implications: The newly developed ceiling‐mounted PV system offers a practical solution to the integration of PV air terminal devices (ATDs) in the vicinity of the workstation. By remotely locating the PV ATDs on the ceiling directly above the occupants and under their control, the conditioned outdoor air is now provided to the occupants through the downward momentum of the air. A secondary air‐conditioning and air distribution system offers additional cooling in the room and maintains a higher ambient temperature, thus offering significant benefits in conserving energy. The results of this study provide designers and consultants with needed knowledge for design of PV systems.
|
|
| 14. |
|
|
| 15. |
|
|
| 16. |
|
|
| 17. |
|
|
| 18. |
|
|
| 19. |
|
|
| 20. |
|
|
| 21. |
|
|
| 22. |
- Yuan, Feng, et al.
(författare)
-
Thermal comfort in hospital buildings - A literature review
- 2022
-
Ingår i: Journal of Building Engineering. - : Elsevier BV. - 2352-7102. ; 45
-
Forskningsöversikt (refereegranskat)abstract
- Hospital buildings are required to secure a variety of indoor environments according to the diverse requirements of patients and staff. Among these requirements, thermal comfort is an important design criterion for indoor environmental quality that affects patients' healing processes and the wellbeing of medical staff. The patients' thermal comfort is given priority due to their medical conditions and impaired immune systems. Thermal comfort and related contexts have been well-covered in many research articles; however, the number of review articles is limited. This article aims to conduct a holistic and critical review of existing studies offering insights on future research trends (180 articles were analyzed). The key research themes are identified using scientometric analysis. Focus is on influencing factors, field-surveys, improving measures and energy saving related to thermal comfort. The primary outcome concludes that ventilation systems play a key role in maintaining acceptable, thermally-comfortable conditions for patients and medical staff. It is also found that acceptable thermal comfort is highly case-dependent and varies substantially based on the health condition of the patient as well as the type and level of staff activities. The measures currently mentioned to minimize energy consumption are also discussed. Some interesting issues, including the inaccuracy arising from the use of predicted mean vote (PMV) and the impact of gender, age, and related factors on thermal comfort, have been noted. This review provides insights into the design and assessment of hospital thermal environments.
|
|
