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Prohibitive equipment cost and certain export regulations are the major obstacles to the widespread adoption of infrared (IR) thermography when evaluating building envelopes. In this work, we propose the use of an affordable and easily available camera as a first step of making the technology accessible. Combined with image post-processing, we hypothesize that a low-cost, low-resolution, and consumer-grade device can provide an economic alternative for the periodic evaluation of building...
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Globally 39% of adults are overweight, 13% are obese, and 9% are underweight. Current thermal comfort standards, catering to the normal weight occupant, may hence be ignoring nearly 60% of the population. This could have significant comfort, productivity and energy implications. We performed a climate chamber study of the thermal response of 76 subjects in all the body mass index (BMI) categories, from 17 and 37 kg/m2. Every participant underwent the same four sessions at average operative...
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In a business as usual scenario, atmospheric carbon dioxide concentration (CO2) could reach 950 parts per million (ppm) by 2100. Indoor CO2 concentrations will rise consequently, given its dependence on atmospheric CO2 levels. If buildings are ventilated following current standards in 2100, indoor CO2 concentration could be over 1300 ppm, depending on specific ventilation codes. Such exposure to CO2 could have physiological and psychological effects on building occupants. We conducted a...
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Building ventilation standards use indoor carbon dioxide (CO2) levels as a proxy for air quality, acknowledging that at typical indoor levels, CO2 itself is not a pollutant. By 2100, outdoor CO2 levels may reach 900 ppm. With current ventilation standards, that would nearly double the levels of chronic, indoor CO2 exposure, raising concerns for its potential effect on occupants. In the last 15 years, an effort to gain this understanding, particularly regarding cognitive performance, has been...
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To enhance indoor climate monitoring and indoor climate assessment, a better understanding of the collection and analysis of monitored data, over longer time periods, is necessary. The goal of this work is to improve long-term monitoring in order to arrive at better performance of building indoor climate, with the perception of occupants in mind. Indoor climate was monitored in an open plan office lay-out in two Case study office buildings, during two periods each. Indoor climate data was...
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Climate models imply that by 2100 atmospheric CO2 levels could exceed 900 ppm. At these levels, subscribing to current ventilation rates would lead to indoor CO2 levels ≥1,400 ppm, possibly impacting our physiology and other responses. We ran a randomized, within-subject study with 15 participants to examine the physiological effects of 2,5 hour exposure to three CO2 levels: 900 ppm, 1450 ppm (reduced ventilation), and 1450 ppm (pure CO2 added, ventilation same as 900 ppm). End-tidal CO2 and...
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The human body emits a wide range of chemicals, including CO2 and isoprene. To examine the impact of cognitive tasks on human emission rates of CO2 and isoprene, we conducted an across-subject, counterbalanced study in a controlled chamber involving 16 adults. The chamber replicated an office environment. In groups of four, participants engaged in 30 min each of cognitive tasks (stressed activity) and watching nature documentaries (relaxed activity). Measured biomarkers indicated higher...