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Sleep is a pillar of human health and wellbeing. In high- and middle-income countries, there is a great reliance on heating, ventilation, and air conditioning systems (HVAC) to control the interior thermal environment in the bedroom. However, these systems are expensive to buy, maintain, and operate while being energy and environmentally intensive—problems that may increase due to climate change. Easily-accessible passive and low-energy strategies, such as fans and electrical heated blankets, address these challenges but their comparative effectiveness for providing comfort in sleep environments has not been studied. We used a thermal manikin to experimentally show that many passive and low-energy strategies are highly effective in supplementing or replacing HVAC systems during sleep. Using passive strategies in combination with low-energy strategies that elevate air movement like ceiling or pedestal fans enhances the cooling effect by three times compared to using fans alone. We extrapolated our experimental findings to estimate heating and cooling effects in two historical case studies: the 2015 Pakistan heat wave and the 2021 Texas power crisis. Passive and low-energy strategies reduced sleep-time heat or cold exposure by 69–91%. The low-energy strategies we tested require one to two orders of magnitude less energy than HVAC systems, and the passive strategies require no energy input. These strategies can also help reduce peak load surges and total energy demand in extreme temperature events. This reduces the need for utility load shedding, which can put individuals at risk of hazardous heat or cold exposure. Our results may serve as a starting point for evidence-based public health guidelines on how individuals can sleep better during heat waves and cold snaps without relying on HVAC. [ABSTRACT FROM AUTHOR]

Indoor Air Quality (IAQ) contributes to the health and comfort of people living and working indoors. Poor IAQ can be linked to indoor and outdoor sources of contaminants. One recent solution for improving IAQ is the use of Electrostatic (ES) air cleaning technology. An ES air cleaner can be installed in a heating, ventilation, and air conditioning system where it pre-filters large dust particles and shocks smaller particles into a collection tray. However, ES air cleaners have been known to give off ozone as a by-product, which is, itself, an air contaminant. Ozone is found outdoors as product of sunlight combining nitrogen oxides and volatile organic compounds generated from man-made pollution. Indoor ozone concentration will depend on the introduction of outdoor ozone indoors through natural ventilation, mechanical ventilation, and infiltration through the building's envelope (in order of importance). Two different ES air cleaners, A and B, were installed in the air conditioning system of research house #2 of the TRANE Residential Heating and Cooling Research Lab at the University of Texas at Tyler. A series of ozone experiments were conducted, which included measuring the baseline ozone levels at the research houses with different levels of insulation, observing the increase in ozone due to the powering on of mechanical ventilation, and observing the increase in ozone due to the powering on of the installed ES air cleaners. The baseline ozone levels observed in research house #2, whose envelope is more tightly insulated, was found to be lower than in research house #1 whose envelope is less tightly insulated. With regards to mechanical ventilation, an increase in ozone levels were seen in addition to an even higher increase in ozone levels when the ES air cleaners were powered on in tandem. In terms of the single contribution of the ES air cleaners in raising indoor ozone levels, the data shows that although the ES air cleaners increased the ozone concentration in the house, the levels are not of concern as they were less than the FDA limit on indoor ozone generation. [ABSTRACT FROM AUTHOR]

BACKGROUND: Despite the substantial role indoor exposure has played in heat wave–related mortality, few epidemiological studies have examined the health effects of exposure to indoor heat. As a result, knowledge gaps regarding indoor heat–health thresholds, vulnerability, and adaptive capacity persist. OBJECTIVE: We evaluated the role of indoor heat exposure on mortality and morbidity among the elderly (=65 years of age) in Houston, Texas. METHODS: Mortality and emergency hospital admission data were obtained through the Texas Department of State Health Services. Summer indoor heat exposure was modeled at the U.S. Census block group (CBG) level using building energy models, outdoor weather data, and building characteristic data. Indoor heat–health associations were examined using time-stratified case-crossover models, controlling for temporal trends and meteorology, and matching on CBG of residence, year, month, and weekday of the adverse health event. Separate models were fitted for three indoor exposure metrics, for individual lag days 0–6, and for 3-d moving averages (lag 0–2). Effect measure modification was explored via stratification on individual- and area-level vulnerability factors. RESULTS: We estimated positive associations between short-term changes in indoor heat exposure and cause-specific mortality and morbidity [e.g., circulatory deaths, odds ratio per 5° C increase = 1:16 (95% CI: 1.03, 1.30)]. Associations were generally positive for earlier lag periods and weaker across later lag periods. Stratified analyses suggest stronger associations between indoor heat and emergency hospital admissions among African Americans compared with Whites. DISCUSSION: Findings suggest excess mortality among certain elderly populations in Houston who are likely exposed to high indoor heat. We developed a novel methodology to estimate indoor heat exposure that can be adapted to other U.S. locations. In locations with high air conditioning prevalence, simplified modeling approaches may adequately account for indoor heat exposure in vulnerable neighborhoods. Accounting for indoor heat exposure may improve the estimation of the total impact of heat on health. [ABSTRACT FROM AUTHOR]

Importance: There is a large body of epidemiologic evidence that heat is associated with increased risk of mortality. One of the most effective strategies to mitigate the effects of heat is through air conditioning (AC); Texas regulates the internal temperature of jails to stay between 65 and 85 °F degrees, but these same standards do not apply to state and private prisons., Objective: To analyze whether heat during warm months is associated with an increased risk of mortality in Texas prisons without AC., Design, Setting, and Participants: This case-crossover study included individuals who died in Texas prisons between 2001 and 2019. The association of heat in warm months with mortality in Texas prisons with and without AC was estimated. Data analysis was conducted from January to April 2022., Exposures: Increasing daily heat index above 85 °F and extreme heat days (days above the 90th percentile heat index for the prison location)., Main Outcomes and Measures: Daily mortality in Texas prisons., Results: There were 2083 and 1381 deaths in prisons without and with AC, respectively, during warm months from 2001 to 2019. Most of the deceased were male (3339 of 3464 [96%]) and the median (IQR) age at death was 54 (45-62) years. A 1-degree increase above 85 °F heat index and an extreme heat day were associated with a 0.7% (95% CI, 0.1%-1.3%) and a 15.1% (95% CI, 1.3%-30.8%) increase in the risk of mortality in prisons without AC, respectively. Approximately 13% of mortality or 271 deaths may be attributable to extreme heat during warm months between 2001 to 2019 in Texas prison facilities without AC. In prisons with AC, a negative percentage change in mortality risk was observed, although the 95% CI crossed zero (percentage change in mortality risk: -0.6%; 95% CI, -1.6% to 0.5%). The estimates in prisons without AC were statistically different than the estimates in prisons with AC (P = .05)., Conclusions and Relevance: This study found an average of 14 deaths per year between 2001 to 2019 were associated with heat in Texas prisons without AC vs no deaths associated with heat in prisons with AC. Adopting an AC policy in Texas prisons may be important for protecting the health of one of our most vulnerable populations.

A cross-sectional study on the home environment and children’s health in Northeast Texas was carried out in 2008–2009. Two thousand eight hundred and nineteen (2,819) parents of children (1–8 years) reported their housing characteristics, home interior surface materials, dampness and children’s health status. The response rate was 71%. Health outcomes studied were wheeze, dry cough, rhinitis, eczema in the last 12 months and diagnosed asthma and hay fever. Dampness was significant risk factor for wheeze and rhinitis with adjusted odds ratio (AOR) 1.3–1.7. Mould/damp spot, condensation and suspected moisture problems were more commonly reported in buildings with flat roof and pier/beam foundation in hot and humid Northeast Texas. Compared to single family houses, trailers were associated with more dampness, consequently a significant increased prevalence of asthma (AOR 1.5 with 95% confidence interval (CI) 1.0–2.3), rhinitis (AOR 1.4, 95% CI 1.0–2.0) and hay fever (AOR 1.5, 95% CI 1.1–2.1). Central air-conditioning system, which re-circulates indoor air, was associated with less dampness problems. However, an increment trend of allergic symptoms was found in homes with air-conditioning system, especially for rhinitis (AOR 1.6, 95% CI 1.1–2.2). Carpet as floor covering and laminated panel as wall covering were associated with rhinitis (AOR 1.6, 95% CI 1.0–2.5) and wheezing (AOR 4.7, 95% CI 1.8–12.7), respectively. [ABSTRACT FROM AUTHOR]

Abstract: This study presents an analysis of a unique dataset of 4971 energy audits performed on homes in Austin, Texas in 2009–2010. We quantify the prevalence of typical air-conditioner design and installation issues such as low efficiency, oversizing, duct leakage, and low measured capacity, and estimate the impacts that resolving these issues would have on peak power demand and cooling energy consumption. We estimate that air-conditioner use in single-family residences currently accounts for 17–18% of peak demand in Austin, and we found that improving equipment efficiency alone could save up to 205MW, or 8%, of peak demand. We estimate that 31% of systems in this study were oversized, leading to up to 41MW of excess peak demand. Replacing oversized systems with correctly sized higher efficiency units has the potential for further savings of up to 81MW. We estimate that the mean system could achieve 18% and 20% in cooling energy savings by sealing duct leaks and servicing their air-conditioning units to achieve 100% of nominal capacity, respectively. Although this analysis is limited to the City of Austin, understanding the methods described herein could allow electric utilities in similar climates to make better-informed decisions when considering efficiency improvement programs. [Copyright &y& Elsevier]

Phthalates and organophosphates are ubiquitous indoor semi-volatile organic contaminants (SVOCs) that have been widely used as plasticizers and flame retardants in consumer products. Although many studies have assessed their levels in house dust, only a few used dust samples captured by filters of building heating, ventilation, and air conditioning (HVAC) systems. HVAC filters collect particles from large volumes of air over a long period of time (potentially known) and thus provide a spatially and temporally integrated concentration. This study measured concentrations of phthalates and organophosphates in HVAC filter dust and settled floor dust collected from low-income homes in Texas, United States, in both the summer and winter seasons. The most frequently detected compounds were benzyl butyl phthalate (BBzP), di-(2-ethylhexyl) phthalate (DEHP), di-n-octyl phthalate (DnOP), tris (1-chloro-2-propyl) phosphate (TCIPP), triphenyl phosphate (TPHP), and tris (1,3-dichloroisopropyl) phosphate (TDCIPP). The median level of TCIPP in settled dust was 3- to 180-times higher than levels reported in other studies of residential homes. Significantly higher concentrations were observed in HVAC filter dust as compared to settled dust for most of the frequently detected compounds in both seasons, except for several phthalates in the winter. SVOC concentrations in settled dust in winter were generally higher than in summer, while different seasonality patterns were found for HVAC filter dust. Settled dust samples from homes with vinyl flooring contained significantly higher levels of BBzP and DEHP as compared to homes with other types of floor material. The concentration of DEHP and TDCIPP in settled dust also significantly associated with the presence of carpet in homes. Cleaning activities to remove dust from furniture actually increased the levels of certain compounds in HVAC filter dust, while frequent vacuuming of carpet helped to decrease the concentrations of some compounds in settled dust. Additionally, the size and age of a given house also correlated with the levels of some pollutants in dust. A statistically significant association between DEHP concentration in HVAC filter dust in summer and the severity of asthma in children was observed. These results suggest that HVAC filter dust represents a useful sampling medium to monitor indoor SVOC concentrations with high sensitivity; in contrast, when using settled dust, in addition to consideration of seasonal influences, it is critical to know the sampling location because the type and level of SVOCs may be related to local materials used there., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

Deals with a study which identified a new serogroup of Legionella pneumophila in veteran patients in July 1980. Description of the patients; Laboratory findings; Serologic testing.

Retail stores contain a wide range of products that can emit a variety of indoor pollutants. Among these chemicals, phthalate esters and polybrominated diphenyl ethers (PBDEs) are two important categories of semi-volatile organic compounds (SVOCs). Filters in heating, ventilation, and air-conditioning (HVAC) system collect particles from large volumes of air and thus potentially provide spatially and temporally integrated SVOC concentrations. This study measured six phthalate and 14 PBDE compounds in HVAC filter dust in 14 retail stores in Texas and Pennsylvania, United States. Phthalates and PBDEs were widely found in the HVAC filter dust in retail environment, indicating that they are ubiquitous indoor pollutants. The potential co-occurrence of phthalates and PBDEs was not strong, suggesting that their indoor sources are diverse. The levels of phthalates and PBDEs measured in HVAC filter dust are comparable to concentrations found in previous investigations of settled dust in residential buildings. Significant correlations between indoor air and filter dust concentrations were found for diethyl phthalate, di-n-butyl phthalate, and benzyl butyl phthalate. Reasonable agreement between measurements and an equilibrium model to describe SVOC partitioning between dust and gas-phase is achieved., (© 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)

The article reports on the opening of a new, state-of-the-art laboratory for fabrics by the Institute of Environmental and Human Health at the Texas Tech University. It states that it will assist the researchers in continuing to create products that can defend the military and civilians. It mentions that the new laboratory air conditioning and humidification system makes faster and more focused research on the technologies of nonwoven fabrics.

Healthcare facilities use nearly twice as much energy per square foot as office buildings, according to American HVAC and air handling equipment manufacturer Temtrol (citing statistics from the country's Green Building Council). As Bruce Anderson, vice-president, Marketing, CES Group LLC (of which Temtrol is a Group company), explains, when America's Dell Children's Medical Center of Central Texas, a paediatric facility built to field-leading environmental performance standards, expanded recently, the hospital's project team selected Temtrol's FANWALL technology for the air handlers used for a new MRI surgical unit "to provide energy-efficient, critical ventilation".

Urban dengue is common in most countries of the Americas, but has been rare in the United States for more than half a century. In 1999 we investigated an outbreak of the disease that affected Nuevo Laredo, Tamaulipas, Mexico, and Laredo, Texas, United States, contiguous cities that straddle the international border. The incidence of recent cases, indicated by immunoglobulin M antibody serosurvey, was higher in Nuevo Laredo, although the vector, Aedes aegypti, was more abundant in Laredo. Environmental factors that affect contact with mosquitoes, such as air-conditioning and human behavior, appear to account for this paradox. We conclude that the low prevalence of dengue in the United States is primarily due to economic, rather than climatic, factors.