Multizone airflow models for calculating infiltration rates in commercial reference buildings

Ng, Lisa C.; Musser, Amy; Persily, Andrew K.; Emmerich, Steven J.

doi:10.1016/j.enbuild.2012.11.035

Cited by 54 publications

(31 citation statements)

References 4 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Air infiltration rates in schools, grocery, and other retail stores were all assumed to equal 0.2/h when calculating C in. This assumed value is based on multizone modeling by Ng et al (2013) that simulated annual airflow using an average building envelope airtightness parameter measured from U.S. commercial buildings. Mean k inf modeled with the HVAC system running ranged between 0.05/h for the hospital reference building, and 0.52/h for the restaurant.…”

Section: Exposure Assessmentmentioning

confidence: 99%

Estimated effect of ventilation and filtration on chronic health risks in U.S. offices, schools, and retail stores

et al. 2015

View full text Add to dashboard Cite

We assessed the chronic health risks from inhalation exposure to volatile organic compounds (VOCs) and particulate matter (PM2.5) in U.S. offices, schools, grocery, and other retail stores and evaluated how chronic health risks were affected by changes in ventilation rates and air filtration efficiency. Representative concentrations of VOCs and PM2.5 were obtained from available data. Using a mass balance model, changes in exposure to VOCs and PM2.5 were predicted if ventilation rate were to increase or decrease by a factor of two, and if higher efficiency air filters were used. Indoor concentrations were compared to health guidelines to estimate percentage exceedances. The estimated chronic health risks associated with VOC and PM2.5 exposures in these buildings were low relative to the risks from exposures in homes. Chronic health risks were driven primarily by exposures to PM2.5 that were evaluated using disease incidence of mortality, chronic bronchitis, and non-fatal stroke. The leading cancer risk factor was exposure to formaldehyde. Using disability-adjusted life years (DALYs) to account for both cancer and non-cancer effects, results suggest that increasing ventilation alone is ineffective at reducing chronic health burdens. Other strategies, such as pollutant source control and the use of particle filtration, should also be considered.

show abstract

Section: Exposure Assessmentmentioning

confidence: 99%

Estimated effect of ventilation and filtration on chronic health risks in U.S. offices, schools, and retail stores

et al. 2015

View full text Add to dashboard Cite

show abstract

“…Based on a previous review paper by the author and the nature of the current study, a fixed value of 0.1 h À1 for k di is deemed to be reasonable and adopted herein [29]. Infiltration for commercial buildings is generally very small compared to the supply air flow [30] and hence it is assumed to be zero. It should be emphasized that infiltration rates and deposition are not sensitive parameters in this study as the removal rate by ventilation is at substantially higher than those values for practical scenarios.…”

Section: Mathematical Modelmentioning

confidence: 99%

Influence of mechanical ventilation system on indoor carbon dioxide and particulate matter concentration

Chan

et al. 2014

Building and Environment

View full text Add to dashboard Cite

a b s t r a c tCommon ventilation strategies may fail to maintain indoor air quality when atmosphere is heavily polluted by particulate matter. This paper evaluates the performances of common constant air volume (CAV) system and variable air volume (VAV) system when carbon dioxide and particles are significantly present in outdoor environment. Major system parameters including filter efficiency, occupancy number, ventilation air rate, and outdoor particle concentration are thoroughly examined. Firstly, a full-scale chamber experiment is performed to investigate the dynamics of CO 2 and airborne particles under steady and non-steady scenarios. The result is further validated with a previously-developed state-space model. Secondly, an exhaustive case study is conducted using an established mathematical model. In order to reduce CO 2 concentration, both CAV and CO 2 -based demand-controlled VAV may cause an undesirable increase in particle concentration when outdoor air is heavily polluted by particles. This dilemma requires further studies on the optimization of ventilation schemes.

show abstract

“…The assumed value of k inf = 0.2/h is based on multizone modeling by Ng et al. () that simulated annual airflow using an average building envelope airtightness parameter measured from US commercial buildings. The parameter k mech is the difference between the measured k oa and assumed k inf .…”

Section: Methodsmentioning

confidence: 99%

“…Measured values of k rec in other studies of retail stores (Bennett et al, 2011;Siegel et al, 2012) suggest 3/h is a reasonable central estimate. The assumed value of k inf = 0.2/h is based on multizone modeling by Ng et al (2013) that simulated annual airflow using an average building envelope airtightness parameter measured from US commercial buildings. The parameter k mech is the difference between the measured k oa and assumed k inf .…”

Section: Estimates Of Indoor Emission Ratesmentioning

confidence: 99%

Cooking‐related PM _2.5 and acrolein measured in grocery stores and comparison with other retail types

et al. 2015

View full text Add to dashboard Cite

We measured particulate matter (PM), acrolein, and other indoor air contaminants in eight visits to grocery stores in California. Retail stores of other types (hardware, furniture, and apparel) were also sampled on additional visits. Based on tracer gas decay data, most stores had adequate ventilation according to minimum ventilation rate standards. Grocery stores had significantly higher concentrations of acrolein, fine and ultrafine PM, compared to other retail stores, likely attributable to cooking. Indoor concentrations of PM2.5 and acrolein exceeded health guidelines in all tested grocery stores. Acrolein emission rates to indoors in grocery stores had a mean estimate about 30 times higher than in other retail store types. About 80% of the indoor PM2.5 measured in grocery stores was emitted indoors, compared to only 20% for the other retail store types. Calculations suggest a substantial increase in outdoor air ventilation rate by a factor of three from current level is needed to reduce indoor acrolein concentrations. Alternatively, acrolein emission to indoors needs to be reduced 70% by better capturing of cooking exhaust. To maintain indoor PM2.5 below the California annual ambient standard of 12 μg/m(3) , grocery stores need to use air filters with an efficiency rating higher than the MERV 8 air filters commonly used today.

show abstract

Multizone airflow models for calculating infiltration rates in commercial reference buildings

Cited by 54 publications

References 4 publications

Estimated effect of ventilation and filtration on chronic health risks in U.S. offices, schools, and retail stores

Estimated effect of ventilation and filtration on chronic health risks in U.S. offices, schools, and retail stores

Influence of mechanical ventilation system on indoor carbon dioxide and particulate matter concentration

Cooking‐related PM _2.5 and acrolein measured in grocery stores and comparison with other retail types

Contact Info

Product

Resources

About

Multizone airflow models for calculating infiltration rates in commercial reference buildings

Cited by 54 publications

References 4 publications

Estimated effect of ventilation and filtration on chronic health risks in U.S. offices, schools, and retail stores

Estimated effect of ventilation and filtration on chronic health risks in U.S. offices, schools, and retail stores

Influence of mechanical ventilation system on indoor carbon dioxide and particulate matter concentration

Cooking‐related PM 2.5 and acrolein measured in grocery stores and comparison with other retail types

Contact Info

Product

Resources

About

Cooking‐related PM _2.5 and acrolein measured in grocery stores and comparison with other retail types