Conditioner Use Research Articles

A Case Study on the Air-conditioner Use of Occupant Behavior in Apartment

The purpose of this study is to analyze the air conditioner (AC) use behavior of occupants based on monitoring data. The indoor temperature and humidity, the occupancy state, and the infrared signal of the AC remote control of 4 households were collected. Using the above data, specific user behavior (on/off, set-temperature, air volume, etc. adjustment) was determined. The collected information on the AC use was divided into three categories based on the occupancy state; entering, leaving, and staying. The probability of turning on and off on the AC according to the DI (discomfort index) while staying the room was also analyzed. The result of this study is significant for future research on predicting the energy consumption propensity of the residents and for developing on AC use model based on user behavior.

Hair product use and breast cancer risk among African American and White women.

Exposures to carcinogens in hair products have been explored as breast cancer risk factors, yielding equivocal findings. We examined hair product use (hair dyes, chemical relaxers and cholesterol or placenta-containing conditioners) among African American (AA) and White women, and explored associations with breast cancer. Multivariable-adjusted models were used to estimate odds ratios (ORs) and 95% confidence intervals (CIs) to describe the associations of interest among 2280 cases (1508 AA and 772 White) and 2005 controls (1290 AA and 715 White). Among controls, hair dye use was more common among Whites than AAs (58 versus 30%), while relaxer (88 versus 5%) and deep conditioner use (59 versus 6%) was more common among AAs. Among AAs, use of dark hair dye shades was associated with increased breast cancer risk (OR = 1.51, 95% CI: 1.20-1.90) and use of dark shades (OR = 1.72, 95% CI: 1.30-2.26) and higher frequency of use (OR = 1.36, 95% CI: 1.01-1.84) were associated with ER+ disease. Among Whites, relaxer use (OR = 1.74, 95% CI: 1.11-2.74) and dual use of relaxers and hair dyes (OR = 2.40, 95% CI: 1.35-4.27) was associated with breast cancer; use of dark hair dyes was associated with increased ER+ disease (OR = 1.54, 95% CI: 1.01-2.33), and relaxer use was associated with increased ER- disease (OR = 2.56, 95% CI: 1.06-6.16). These novel findings provide support a relationship between the use of some hair products and breast cancer. Further examinations of hair products as important exposures contributing to breast cancer carcinogenesis are necessary.

Investigation and modeling of the residential infiltration of fine particulate matter in Beijing, China

ABSTRACTThe objective of this study was to estimate the residential infiltration factor (Finf) of fine particulate matter (PM2.5) and to develop models to predict PM2.5 Finf in Beijing. Eighty-eight paired indoor–outdoor PM2.5 samples were collected by Teflon filters for seven consecutive days during both non-heating and heating seasons (from a total of 55 families between August, 2013 and February, 2014). The mass concentrations of PM2.5 were measured by gravimetric method, and elemental concentrations of sulfur in filter deposits were determined by energy-dispersive x-ray fluorescence (ED-XRF) spectrometry. PM2.5 Finf was estimated as the indoor/outdoor sulfur ratio. Multiple linear regression was used to construct Finf predicting models. The residential PM2.5 Finf in non-heating season (0.70 ± 0.21, median = 0.78, n = 43) was significantly greater than in heating season (0.54 ± 0.18, median = 0.52, n = 45, p < 0.001). Outdoor temperature, window width, frequency of window opening, and air conditioner use were the most important predictors during non-heating season, which could explain 57% variations across residences, while the outdoor temperature was the only predictor identified in heating season, which could explain 18% variations across residences. The substantial variations of PM2.5 Finf between seasons and among residences found in this study highlight the importance of incorporating Finf into exposure assessment in epidemiological studies of air pollution and human health in Beijing. The Finf predicting models developed in this study hold promise for incorporating PM2.5 Finf into large epidemiology studies, thereby reducing exposure misclassification.Implications: Failure to consider the differences between indoor and outdoor PM2.5 may contribute to exposure misclassification in epidemiological studies estimating exposure from a central site measurement. This study was conducted in Beijing to investigate residential PM2.5 infiltration factor and to develop a localized predictive model in both nonheating and heating seasons. High variations of PM2.5 infiltration factor between the two seasons and across homes within each season were found, highlighting the importance of including infiltration factor in the assessment of exposure to PM2.5 of outdoor origin in epidemiological studies. Localized predictive models for PM2.5 infiltration factor were also developed.

Phase Equilibrium and Formation Behavior of the CO2–TBPB Semiclathrate Hydrate for Cold Storage Applications

Cold thermal storage is primarily used for demand management on electricity grids due to air conditioner use. The CO2 hydrate has been widely studied as a cold storage medium for its proper phase equilibrium temperature range and large latent heat. This study presents experimental work on the phase equilibrium behavior of the CO2 hydrate under applicable pressures (<10 bar) for the potential to use in air conditioning systems. The formation of hydrate was aided by tetra-n-butylphosphonium bromide (TBPB) at mass fractions of 10, 20, 30, and 37 wt % to lower the required pressure. Instead of using complex calorimeters, the enthalpy of the CO2–TBPB hydrate was measured using a modified T-history method in a self-fabricated pressure tube. Through this test, the enthalpy of the CO2–TBPB hydrate was found to be much higher than for other normally used phase change materials. However, the hydrate formation was also manifested in a large degree of supercooling and a long induction delay. To reduce them, secondary...

How do household characteristics affect appliance usage? Application of conditional demand analysis to Japanese household data

Although both appliance ownership and usage patterns determine residential electricity consumption, it is less known how households actually use their appliances. In this study, we conduct conditional demand analyses to break down total household electricity consumption into a set of demand functions for electricity usage, across 12 appliance categories. We then examine how the socioeconomic characteristics of the households explain their appliance usage. Analysis of micro-level data from the Nation Survey of Family and Expenditure in Japan reveals that the family and income structure of households affect appliance usage. Specifically, we find that the presence of teenagers increases both air conditioner and dishwasher use, labor income and nonlabor income affect microwave usage in different ways, air conditioner usage decreases as the wife's income increases, and microwave usage decreases as the husband's income increases. Furthermore, we find that households use more electricity with new personal computers than old ones; this implies that the replacement of old personal computers increases electricity consumption.

Association between Prenatal Environmental Factors and Child Autism: A Case Control Study in Tianjin, China

ObjectiveTo investigate the association between autism and prenatal environmental risk factors. MethodsA case-control study was conducted among 193 children with autism from the special educational schools and 733 typical development controls matched by age and gender by using questionnaire in Tianjin from 2007 to 2012. Statistical analysis included quick unbiased efficient statistical tree (QUEST) and logistic regression in SPSS 20.0. ResultsThere were four predictors by QUEST and the logistic regression analysis, maternal air conditioner use during pregnancy (OR=0.316, 95% CI: 0.215-0.463) was the single first-level node (χ2=50.994, P=0.000); newborn complications (OR=4.277, 95% CI: 2.314-7.908) and paternal consumption of freshwater fish (OR=0.383, 95% CI: 0.256-0.573) were second-layer predictors (χ2=45.248, P=0.000; χ2=24.212, P=0.000); and maternal depression (OR=4.822, 95% CI: 3.047-7.631) was the single third-level predictor (χ2=23.835, P=0.000). The prediction accuracy of the tree was 89.2%. ConclusionThe air conditioner use during pregnancy and paternal freshwater fish diet might be beneficial for the prevention of autism, while newborn complications and maternal depression might be the risk factors.

Sleep quality and air conditioner use

Airflow is an effective way to increase heat loss - an ongoing process during sleep and wakefulness in daily life. In a previous study, alleviation of heat by increased isothermal airflow reduced wakefulness, skin temperature, rectal temperature, and sweating during sleep at 32 °C with 80% relative humidity [1]. In this study, experiments were conducted to determine the effect on sleep of varying airflow velocity from air conditioners, using 10 healthy young men (age 23.0 +/- 3.6 years; height 170.9 +/- 3.6cm; mass 62.2 +/- 6.8kg) as subjects.

Hair care practices and structural evaluation of scalp and hair shaft parameters in African American and Caucasian women.

How African American hair fragility relates to hair care practices and biologic differences between races is not well understood. To assess the differences between perceptions of hair health, hair care practices, and several biologic hair parameters between Caucasian and African American women. A questionnaire on perceptions of hair health and hair care practices was administered. Biological and structural parameters of hair shaft and scalp, including growth, density, diameter, cycle, breakage, and scalp blood flow were also assessed in this case-control study. Significant differences between the Caucasian and African American women were observed in the questionnaire and biologic study data. Regarding self-reported perceptions of hair health, there were differences in the following: hair shaft type (P<0.001), hair breakage (P=0.040), and desire to change hair (P=0.001). Regarding self-reported hair care practices, there were differences in the following: location of haircutting (P=0.002) and washing (P=0.010), washing frequency (P<0.001), chemical relaxer use (P<0.001), hooded hair dryer use (P<0.001), and hair shaft conditioner use (P=0.005). The two groups had similar practices in regard to the use of hair color, frequency of hair color use, chemical curling agents, and handheld blow dryer use. Regarding biological and structural parameters, there were differences in the following: hair growth rate (P<0.001), density (P=0.0016), diameter (P=0.01), number of broken hairs (P<0.001), and blood flow (P=0.03). There was no significant difference in hair cycle parameters.The differences in hair care practices and hair fiber morphology among African American women may contribute to clinically observed variation in hair fragility and growth.

Modeling Past And Future Mortality Effects Of Temperatures Accounting For Adaptation

While climate change will inevitably lead to warmer temperatures, the impact of these changes on future mortality risks remains unclear, due in part to large uncertainties in the magnitude of future exposure-response functions. Studies have shown that the impact of temperature on daily deaths varies considerably by location and time, including time of year, and it is reasonable to assume that further changes will occur as cities develop and adapt in coming decades. We modeled changes in exposure-response over time, time of year, and space in relation to a range of adaptation-related factors (mean temperature and air conditioner usage) then projected future mortality impacts taking into account both climate change and projected trends in those factors. We used Poisson regression to estimate monthly functions relating daily average temperature to excess mortality in 209 U.S. cities in five-year intervals from 1973 to 2006. In a second stage, we meta regressed the effect estimates on average monthly temperature and percent air conditioner use, controlling also for time, race, cluster and month. We developed daily average temperature projections at 1 degree spatial resolution using two climate models, each run with the RCP 6.0 emission scenario. Results showed diminished heat effects and enhanced cold effects in locations and at time periods with higher mean temperatures. A/C use was associated with a reduction in mortality effects of very high temperatures. Projections into the future using exposure-response functions modified by mean temperature showed reduced mortality effects of both hot and cold temperatures as compared with “naïve” analyses that simply held exposure-response constant in the future, with, for example, between 10 and 33 additional temperature-related deaths per million population in 2050 depending on the climate model. Results illustrate the potential influence of adaptation in modifying future climate impacts on premature mortality.

Effect of poverty on the relationship between personal exposures and ambient concentrations of air pollutants in Ho Chi Minh City

Socioeconomic factors often affect the distribution of exposure to air pollution. The relationships between health, air pollution, and poverty potentially have important public health and policy implications, especially in areas of Asia where air pollution levels are high and income disparity is large. The objective of the study was to characterize the levels, determinants of exposure, and relationships between children personal exposures and ambient concentrations of multiple air pollutants amongst different socioeconomic segments of the population of Ho Chi Minh City, Vietnam. Using repeated (N = 9) measures personal exposure monitoring and determinants of exposure modeling, we compared daily average PM2.5, PM10, PM2.5 absorbance and NO2 concentrations measured at ambient monitoring sites to measures of personal exposures for (N = 64) caregivers of young children from high and low socioeconomic groups in two districts (urban and peri-urban), across two seasons. Personal exposures for both PM sizes were significantly higher among the poor compared to non-poor participants in each district. Absolute levels of personal exposures were under-represented by ambient monitors with median individual longitudinal correlations between personal exposures and ambient concentrations of 0.4 for NO2, 0.6 for PM2.5 and PM10 and 0.7 for absorbance. Exposures of the non-poor were more highly correlated with ambient concentrations for both PM size fractions and absorbance while those for NO2 were not significantly affected by socioeconomic position. Determinants of exposure modeling indicated the importance of ventilation quality, time spent in the kitchen, air conditioner use and season as important determinant of exposure that are not fully captured by the differences in socioeconomic position. Our results underscore the need to evaluate how socioeconomic position affects exposure to air pollution. Here, differential exposure to major sources of pollution, further influenced by characteristics of Ho Chi Minh City's rapidly urbanizing landscape, resulted in systematically higher PM exposures among the poor.

Predictors of urinary bisphenol A and phthalate metabolite concentrations in Mexican children

Exposure to endocrine disrupting chemicals such as bisphenol A (BPA) and phthalates is prevalent among children and adolescents, but little is known regarding important sources of exposure at these sensitive life stages. In this study, we measured urinary concentrations of BPA and nine phthalate metabolites in 108 Mexican children aged 8–13years. Associations of age, time of day, and questionnaire items on external environment, water use, and food container use with specific gravity-corrected urinary concentrations were assessed, as were questionnaire items concerning the use of 17 personal care products in the past 48-h. As a secondary aim, third trimester urinary concentrations were measured in 99 mothers of these children, and the relationship between specific gravity-corrected urinary concentrations at these two time points was explored. After adjusting for potential confounding by other personal care product use in the past 48-h, there were statistically significant (p<0.05) positive associations in boys for cologne/perfume use and monoethyl phthalate (MEP), mono(3-carboxypropyl) phthalate (MCPP), mono(2-ethyl-5-hydroxyhexyl) phthalate (MEHHP), and mono(2-ethyl-5-oxohexyl) phthalate (MEOHP), and in girls for colored cosmetics use and mono-n-butyl phthalate (MBP), mono(2-ethylhexyl) phthalate (MEHP), MEHHP, MEOHP, and mono(2-ethyl-5-carboxypentyl) phthalate (MECPP), conditioner use and MEP, deodorant use and MEP, and other hair products use and MBP. There was a statistically significant positive trend for the number of personal care products used in the past 48-h and log-MEP in girls. However, there were no statistically significant associations between the analytes and the other questionnaire items and there were no strong correlations between the analytes measured during the third trimester and at 8–13years of age. We demonstrated that personal care product use is associated with exposure to multiple phthalates in children. Due to rapid development, children may be susceptible to impacts from exposure to endocrine disrupting chemicals; thus, reduced or delayed use of certain personal care products among children may be warranted.

A parametric study of energy savings from cleaning coils and filters in constant air volume HVAC systems

This study evaluates the energy savings resulting from the remediation of coil and filter fouling in constant air volume HVAC systems in residential and small commercial buildings. A computer model was developed to simulate the behavior of buildings and their duct systems under various levels of fouling. The model was verified through laboratory and field testing. Parametric simulation and sensitivity analysis results suggest that although fouling can have an impact on both air conditioner and furnace energy use, for the levels of fouling found in the literature, energy savings will be negligible for residential buildings and negative for small commercial buildings.

Garden management and soil fertility in Flemish domestic gardens

Collectively domestic gardens form an important landscape component, but environmental and land use policies tend to ignore domestic gardens. This paper investigates nutrient cycling in domestic gardens: fertilizer and soil conditioner use, composting, removal of grass clippings and the soil fertility states in the case of Flanders (the northern part of Belgium). Data was assembled from an internet survey about garden management and a database on soil fertility of domestic gardens. The combined analysis of these data reveals new insight in the link between garden management and the chemical condition in gardens (in terms of soil carbon content, pH and phosphate). Flemish gardeners used 0.07kg fertilizer and removed 2.3l grass clippings per m2 garden in 2007. Meanwhile, garden soils appear to have a higher pH and phosphorus content and lawns a lower carbon content than optimal agronomic standards. These insights show that gardens are a dynamic socio-ecological system with considerable nutrient flows from and to the household and the environment, indicating the need for more detailed and systematic environmental monitoring. This way, domestic gardens can be compared to agriculture, horticulture and other land use types. This and complementary research helps to complete insights in the dynamics across complex rural and urban landscapes. Future research should take into account, among other things, prevailing practices and habits of garden owners.

Staying cool in a changing climate: Reaching vulnerable populations during heat events

The frequency and intensity of hot weather events are expected to increase globally, threatening human health, especially among the elderly, poor, and chronically ill. Current literature indicates that emergency preparedness plans, heat health warning systems, and related interventions may not be reaching or supporting behavior change among those most vulnerable in heat events. Using a qualitative multiple case study design, we comprehensively examined practices of these populations to stay cool during hot weather (“cooling behaviors”) in four U.S. cities with documented racial/ethnic and socio-economic disparities and diverse heat preparedness strategies: Phoenix, Arizona; Detroit, Michigan; New York City, New York; and Philadelphia, Pennsylvania. Based on semi-structured in-depth interviews we conducted with 173 community members and organizational leaders during 2009–2010, we assessed why vulnerable populations do or do not participate in health-promoting behaviors at home or in their community during heat events, inquiring about perceptions of heat-related threats and vulnerability and the role of social support. While vulnerable populations often recognize heat's potential health threats, many overlook or disassociate from risk factors or rely on experiences living in or visiting warmer climates as a protective factor. Many adopt basic cooling behaviors, but unknowingly harmful behaviors such as improper use of fans and heating and cooling systems are also adopted. Decision-making related to commonly promoted behaviors such as air conditioner use and cooling center attendance is complex, and these resources are often inaccessible financially, physically, or culturally. Interviewees expressed how interpersonal, intergenerational relationships are generally but not always protective, where peer relationships are a valuable mechanism for facilitating cooling behaviors among the elderly during heat events. To prevent disparities in heat morbidity and mortality in an increasingly changing climate, we note the implications of local context, and we broadly inform heat preparedness plans, interventions, and messages by sharing the perspectives and words of community members representing vulnerable populations and leaders who work most closely with them.

Racial and Income Disparities in Relation to a Proposed Climate Change Vulnerability Screening Method for California

Racial and Income Disparities in Relation to a Proposed Climate Change Vulnerability Screening Method for California Paul English, California Department of Public Health, CA, USA Max Richardson, California Department of Public Health, CA, USA Rachel Morello-Frosh, University of California, CA, USA Manuel Pastor, University of Southern California, CA, USA James Sadd, Occidental College, CA, USA Galatea King, CA Dept of Public Health, CA, USA William Jesdale, University of California, CA, USA Michael Jerrett, University of California, CA, USA Abstract: A key component for public health adaptation strategies for local communities and governments is the development of methods for climate change population vulnerability screening. There have been few attempts to combine multiple climate change threats in a measure which addresses a more holistic concept of population vulnerability that includes ex- posure, population sensitivity, and adaptive capacity. We propose a screening method to identify populations at high risk from climate change impacts using population vulnerability and the effects of cumulative stressors. We also investigate if racial/ethnic and income disparities interact with climate change vulnerability. We chose several metrics based on the literature and data availability at the sub-county (census tract) level for two California counties. They included measures of exposure related to climate change (sea-level rise, flood risk, and wildfire risk); measures of population sensitivity (elderly living alone and car ownership); and measures of adaptive capacity (tree canopy, impervious surfaces, air conditioner use, and public transit ac- cess). We add a previously developed index (Environmental Justice Screening Method) which reflects measures of cumulative impacts. Validation was conducted by using emergency room data from a recent extreme weather event. Analysis of the final scores showed the highest vul- nerability in the urban areas, except also at the coast in Los Angeles County. African-Americans and Latinos were more likely to reside in the top two vulnerability areas in both counties compared to whites, and median household income was inversely linearly related to vulnerab- ility risk score. We present a simple and transparent screening tool which could be developed in other regions and could be modified in order to best assess the risks that are of the greatest concern in communities. Keywords: Vulnerability, Screening, Racial/Income Disparities INTRODUCTION W ith the failure of the U.S. to ratify the Kyoto protocols and the persistent recession of western economies diverting attention away from greenhouse gas reduction policies, the public health community has started to focus more on climate change adaptation, rather than mitigation. A key component for public health adaptation strategies for local communities and governments is a method to identify popula- tions most vulnerable to climate change. The International Journal of Climate Change: Impacts and Responses Volume 4, 2013, http://on-climate.com/, ISSN 1835-7156 © Common Ground, Paul English, Max Richardson, Rachel Morello-Frosh, Manuel Pastor, James Sadd, Galatea King, William Jesdale, Michael Jerrett, All Rights Reserved, Permissions: cg-support@commongroundpublishing.com

Transformer and home energy management systems to lessen electrical vehicle impact on the grid

This study discusses how increased deployment of electric vehicles (EVs) acts as a catalyst for development of transformer and home energy management systems in order to reduce the impact of EV battery charging on distribution transformers. The analysis uses actual load consumption data from Austin, Texas, during a typical summer day. It also considers a case of high-density penetration of electric vehicle in line with plans announced as part of Austin's Pecan Street smart grid initiative. The presented discussion describes first that because of air conditioner use, both during day and at night, power consumption remains relatively constant throughout the day, which creates issues even when considering charging EVs at night. In particular, the analysis anticipates that in such areas with high density of EVs and where air conditioner load is also present at night, distribution transformer life may be reduced unless EV charging is managed adequately.

Keeping Cool: Use of Air Conditioning by Australians with Multiple Sclerosis

Despite the known difficulties many people with MS have with high ambient temperatures, there are no reported studies of air conditioning use and MS. This study systematically examined air conditioner use by Australians with MS. A short survey was sent to all participants in the Australian MS Longitudinal Study cohort with a response rate of 76% (n = 2,385). Questions included hours of air-conditioner use, areas cooled, type and age of equipment, and the personal effects of overheating. Air conditioners were used by 81.9% of respondents, with an additional 9.6% who could not afford an air conditioner. Regional and seasonal variation in air conditioning use was reported, with a national annual mean of 1,557 hours running time. 90.7% reported negative effects from overheating including increased fatigue, an increase in other MS symptoms, reduced household and social activities, and reduced work capacity. Households that include people with MS spend between 4 and 12 times more on keeping cool than average Australian households.

Quantifying the health impacts of future changes in temperature in California

BackgroundSeveral epidemiological studies demonstrate associations between high summer temperatures and increased mortality. However, the quantitative implications of projected future increases in temperature have not been well characterized. ObjectiveThis study quantifies the effects of projected future temperatures on both mortality and morbidity in California, including the potential effects of mitigation. Data and methodsWe first estimated the association between temperature and mortality for populations close to weather stations throughout the state. These dose–response estimates for mortality were then combined with local measures of current and projected changes in population, and projected changes in temperature, using a baseline of average temperatures from 1961 to 1990, for the years 2025 and 2050. The latter were based on two greenhouse gas emissions scenarios (A2 and B1) developed for the Intergovernmental Panel on Climate Change. In addition, we assessed the impacts of future adaptation through use of air conditioners. Several sensitivity analyses were conducted to determine the likely range of estimates. ResultsThese analyses indicate that for the high emissions scenario, the central estimate of annual premature mortality ranges from 2100 to 4300 for the year 2025 and from 6700 to 11,300 for 2050. The highest estimates are from the models that use age-specific dose–response functions, while the low estimates are from the models that adjust for ozone. Estimates using the low emissions scenario are roughly half of these estimates. Mitigation based on our estimates of the effects of 10% and 20% increase in air conditioner use would generate reductions of 16% and 33% in the years 2025 and 2050, respectively. ConclusionOur estimates suggest significant public health impacts associated with future projected increases in temperature.

Racial/Ethnic Differences in Hormonally-Active Hair Product Use: A Plausible Risk Factor for Health Disparities

Estrogen and endocrine-disrupting chemicals (EDCs) that are associated with several health outcomes have been found in hair products. We evaluated the proportion, frequency, duration, and content of hair products in a racially/ethnically diverse population. We recruited n = 301 African-American, African-Caribbean, Hispanic, and white women from the New York metropolitan area. We collected data on hair oil, lotion, leave-in conditioner, root stimulator, perm, and other product use. Estrogen and EDC information was collected from commonly used hair products' labels (used by >3% of population). African-American and African-Caribbean women were more likely to use all types of hair products compared to white women (P < 0.0001). Among hair product users, frequency varied significantly by race/ethnicity, but not duration. More African-Americans (49.4%) and African-Caribbeans (26.4%) used products containing placenta or EDCs compared to whites (7.7%). African-American and African-Caribbean women were more likely to be exposed to hormonally-active chemicals in hair products.

Predictors of airborne endotoxin concentrations in inner city homes

Few studies have assessed in home factors which contribute to airborne endotoxin concentrations. In 85 inner city Baltimore homes, we found no significant correlation between settled dust and airborne endotoxin concentrations. Certain household activities and characteristics, including frequency of dusting, air conditioner use and type of flooring, explained 36–42% of the variability of airborne concentrations. Measurements of both airborne and settled dust endotoxin concentrations may be needed to fully characterize domestic exposure in epidemiologic investigations.