Previous studies – primarily in high income countries – have shown that high prenatal temperatures are associated with adverse birth outcomes. However, these studies are mostly focused on average exposure across the full gestational period or short-term exposure immediately prior to delivery and may miss important sensitive windows of exposure in utero. Further, nearly all use ambient air temperature data, which neglect physiologically important interactions between air temperature and humidity. The Ghana Randomized Air Pollution and Health Study (GRAPHS) recruited pregnant individuals from 2013 to 2015 from communities in the Kintampo North Municipality and Kintampo South District of Ghana. We estimated daily maximum shaded wet bulb globe temperature (WBGTmax) and heat index (HImax) during pregnancy and examined associations with birth weight, birth length, head circumference, and incidence of low birth weight, preterm birth, and small for gestational age. Using linear regression analyses, trimester average models identified that higher WBGTmax in the first trimester was associated with larger head circumference; second trimester was associated with shorter birth length, lower birth weight and higher odds of preterm birth, and third trimester was associated with shorter gestational age and larger head circumference. Time-varying analyses using distributed lag nonlinear models find that, compared to the median, lower WBGTmax and HImax (25th percentile) during the first half of pregnancy was associated with higher birth weight and longer birth length. Compared to the median, lower WBGTmax and HImax (25th percentile) in the second half of pregnancy was associated with smaller head circumference while higher wet bulb globe temperature (75th percentile) was associated with larger head circumference. Overall, our study identified that higher WBGTmax and HImax are associated with pregnancy duration and newborn size. Given the overall trend in our study area of rising temperatures, these data suggest that adaptation strategies are urgently needed to protect child health.

Hot and humid heat exposures challenge the health of outdoor workers engaged in occupations such as construction, agriculture, first response, manufacturing, military, or resource extraction. Therefore, government institutes developed guidelines to prevent heat‐related illnesses and death during high heat exposures. The guidelines use Wet Bulb Globe Temperature (WBGT), which integrates temperature, humidity, solar radiation, and wind speed. However, occupational heat exposure guidelines cannot be readily applied to outdoor work places due to limited WBGT validation studies. In recent years, institutions have started providing experimental WBGT forecasts. These experimental products are continually being refined and have been minimally validated with ground‐based observations. This study evaluated a modified WBGT hindcast using the historical National Digital Forecast Database and the European Centre for Medium‐Range Weather Forecasts Reanalysis v5. We verified the hindcasts with hourly WBGT estimated from ground‐based weather observations. After controlling for geographic attributes and temporal trends, the average difference between the hindcast and in situ data varied from −0.64°C to 1.46°C for different Köppen‐Geiger climate regions, and the average differences are reliable for decision making. However, the results showed statistically significant variances according to geographical features such as aspect, coastal proximity, land use, topographic position index, and Köppen‐Geiger climate categories. The largest absolute difference was observed in the arid desert climates (1.46: 95% CI: 1.45, 1.47), including some parts of Nevada, Arizona, Colorado, and New Mexico. This research investigates geographic factors associated with systematic WBGT differences and points toward ways future forecasts may be statistically adjusted to improve accuracy.

Wet-bulb globe temperature (WBGT)-a standard measure for workplace heat stress regulation-incorporates the complex, nonlinear interaction among temperature, humidity, wind and radiation. This complexity requires WBGT to be calculated iteratively following the recommended approach developed by Liljegren and colleagues. The need for iteration has limited the wide application of Liljegren's approach, and stimulated various simplified WBGT approximations that do not require iteration but are potentially seriously biased. By carefully examining the self-nonlinearities in Liljegren's model, we develop a zero-iteration analytic approximation of WBGT while maintaining sufficient accuracy and the physical basis of the original model. The new approximation slightly deviates from Liljegren's full model-by less than 1°C in 99% cases over 93% of global land area. The annual mean and 75%-99% percentiles of WBGT are also well represented with biases within ± 0.5 °C globally. This approximation is clearly more accurate than other commonly used WBGT approximations. Physical intuition can be developed on the processes controlling WBGT variations from an energy balance perspective. This may provide a basis for applying WBGT to understanding the physical control of heat stress.

ISO 7243 considers the WBGT (Wet Bulb Globe Temperature) index as an index of thermal stress in hot environments. It can be evaluated directly by measuring the globe temperature, the natural wet bulb temperature, and the air temperature (only outside in the presence of solar radiation) or, indirectly, by measuring the air temperature, the air velocity, the humidity and the mean radiant temperature. The globe and natural wet bulb temperatures can only be estimated empirically, because they are not thermodynamic properties. The direct method, thus, permits neither very accurate measurements nor direct traceability. The aim of this study is to compare the above-mentioned methodologies experimentally. This analysis was carried out by varying the thermal and fluid dynamic parameters for transversal flow in the common measurement range.

Extreme heat exacerbates human illness and constrains the intensity and/or duration of outdoor activities. Temperature is an incomplete metric of outdoor heat exposures. By contrast, Wet Bulb Globe Temperature (WBGT) is a heat exposure metric that considers air temperature, moisture, solar radiation, and wind speed. In the USA, bicycle activity increased by 60% from 2000 to 2010. Several studies examined weather conditions and bicycling activities. However, few studies examined how the public should conduct their daily physical activities per weather conditions.This study investigated the relationship between WBGT and shared city bicycle activity in New York City (NYC) and San Francisco (SF), USA. Generalized Additive Models examined nonlinear relationships between WBGT and bicycle activity while controlling for rider demographics and temporal trends. Next, bootstrapping estimated the "peak point", when the relationship between the bike rentals and WBGT notably changed.The analysis also examined whether the heat warning messages affected cycling activities. We found that the number of rented bikes declined at different peak points in each city. The peak point was in NYC at 34.3°C (95% CI 33°C-35°C) and 10.8°C (95% CI 10-12°C) in SF. Somewhat paradoxically, bike rentals increased when heat warnings were issued in both cities.

The Wet Bulb Globe Temperature (WBGT) index is a standard for assessing environmental heat stress, but the requirement of expensive instrument with specialized maintenance is limited its use. This study aims to develop the empirical equation to estimate the WBGT from Heat Index (HI) calculated from portable temperature and humidity recorder (THR), based on the data collected at seven sites covering all regions of Thailand. Comparative analysis shows that the HI values calculated from THR (HITHR) are consistent well with those measured from the thermal environmental monitor (HIQT36) as evidenced by a highly positive correlation between them (r=0.97; p<0.01; n=4,303). These results suggest high reliability of the portable THR and its acceptance to be used instead of the standard QT36 device. Based on a simple linear regression developed to estimate WBGT from the HITHR, it was found that the model accounts for at least 90% of the variance of the observed WBGT (dependent variable). In addition, validation of the model with the statistical methods shows relatively small errors of the estimated WBGT values in comparison to the observed values. With this evidence, the developed empirical regression equation can be used to estimate WBGT with high accuracy and confidence. Simple and easier to use for the practitioners who are involved in public health works at community level, a heat monitoring tool kit consisting of a THR, WBGT chart and recommended actions were further developed bas

The Wet Bulb Globe Temperature (WBGT) index is a standard for assessing environmental heat stress, but the requirement of expensive instrument with specialized maintenance is limited its use. This study aims to develop the empirical equation to estimate the WBGT from Heat Index (HI) calculated from portable temperature and humidity recorder (THR), based on the data collected at seven sites covering all regions of Thailand. Comparative analysis shows that the HI values calculated from THR (HITHR) are consistent well with those measured from the thermal environmental monitor (HIQT36) as evidenced by a highly positive correlation between them (r=0.97; p<0.01; n=4,303). These results suggest high reliability of the portable THR and its acceptance to be used instead of the standard QT36 device. Based on a simple linear regression developed to estimate WBGT from the HITHR, it was found that the model accounts for at least 90% of the variance of the observed WBGT (dependent variable). In addition, validation of the model with the statistical methods shows relatively small errors of the estimated WBGT values in comparison to the observed values. With this evidence, the developed empirical regression equation can be used to estimate WBGT with high accuracy and confidence. Simple and easier to use for the practitioners who are involved in public health works at community level, a heat monitoring tool kit consisting of a THR, WBGT chart and recommended actions were further developed bas

The wet-bulb globe temperature (WBGT) is a measure of environmental heat as it affects humans and animals. Unlike a simple temperature measurement, WBGT The wet-bulb globe temperature (WBGT) is a measure of environmental heat as it affects humans and animals. Unlike a simple temperature measurement, WBGT accounts for air temperature, humidity, heat radiation (from hot objects like the Sun or a furnace), and air movement (wind or ventilation). WBGT was developed in the 1950s as a part of an effort to reduce heat related illness and death during US The wet-bulb globe temperature (WBGT) is a measure of environmental heat as it affects humans and animals. Unlike a simple temperature measurement, WBGT accounts for air temperature, humidity, heat radiation (from hot objects like the Sun or a furnace), and air movement (wind or ventilation). WBGT was developed in the 1950s as a part of an effort to reduce heat related illness and death during US military training. Today, it is used by industrial hygienists, athletes, sporting events, and militaries to determine appropriate exposure levels to high temperatures. A WBGT meter combines three sensors, a dry-bulb thermometer, a natural (static) wet-bulb thermometer, and a black globe thermometer (for radiant heat), which together measure environmental conditions and calculates a single value representing overall heat stress For outdoor environments, the meter uses all sensor data inputs, calculating WBGT as: Tw = Natural wet-bulb temperature (combined with dry-bulb temperature indicates humidity) Tg = Globe thermometer temperature (measured with a globe thermometer, also known as a black globe thermometer) Td = Dry-bulb temperature (actual air temperature) Temperatures may be in either Celsius or Fahrenheit Indoors the following formula is used:

Interactive videodisc calorimetry simulations for exercise physiology laboratories. Six interactive videodisc lessons for college-level exercise physiology classes were developed. The six lessons were written using TenCore for the IBM M-Motion technology. The focus of the laboratories is on exercise metabolism measured by indirect calorimetry. The six lessons are as follows. 1) Environmental measures: determines whether conditions are favorable for exercise. Dry bulb, wet bulb, and black globe temperatures are obtained to calculate relative humidity, STPD gas volumes, and the wet bulb-globe temperature index. 2) Basal metabolism: emphasizes the mechanics of calculating energy expenditure through indirect calorimetry. Lying, sitting, and exercise metabolism are compared. 3) Submaximal metabolism: compares the energy cost of walking a mile and running a mile. Steady-state exercise, oxygen debt, and oxygen deficit are explored. 4) Maximal metabolism: assesses maximal oxygen consumption using the Bruce protocol. 5) Hormonal responses to prolonged exercise: demonstrates the effect of hormonal levels on %fat and %carbohydrate utilization during 1 h of exercise.

temperature and humidity. Besides the heat index, other measures of apparent temperature include the Canadian humidex, the wet-bulb globe temperature The heat index (HI) is a measure of temperature as perceived by humans, combining actual air temperature and relative humidity, in shaded areas; it takes into account that elevated humidity makes hot ambient temperature feel higher than the same temperature with lower humidity, as evaporative cooling of sweat is less effective. For example, when the temperature is 32 °C (90 °F) but relative humidi The…

sunlight. The wet-bulb-globe temperature index is cal- culated using 70 per cent wet-bulb tempera- ture … wherein temperatures can be controlled from —5 to 125°F, +1°F dry-bulb temperature, and relative humidity … dry-bulb temperature of approximately 2° F. Recent data indicate that in the range of dry- bulb temperatures