Prototype uses sensors to assess the conditions of indoor environments
Brazilian research station in the Antarctic: the summer sun is almost always in the sky, while darkness reigns in the winter
Brazilian Navy
At night, close the window a little, open the bedroom door, leave the living room and go to sleep, but don’t sleep too much. In response to excess light or carbon gas (CO₂) and irregular sleep patterns, recommendations of this type may become common in residences, refectories, meeting rooms, train stations, building entrances, and other closed public spaces, as is already the case with street clocks measuring ozone and atmospheric pollution.
This is the goal of a group of architects, engineers, and physicists from the Federal University of Espírito Santo (UFES), which has developed a monitor for inside spaces. Described in an article published in the Journal Internet of Things in January, the device assesses air and light quality, and can generate individual instructions, issue general warnings, or be used to manage the wellness of students, professors, and other professionals. The prototype, whose third version is currently being tested, is a white disc 15 centimeters (cm) in diameter; the fourth version, under construction, is hexagonal, similar to wall clocks without second or minute hands.
Without any known similar tools, the UFES device uses a group of apparatus that normally function separately: sensors for individual light beam intensity, humidity, temperature, and CO₂. There is also a Bluetooth communication system that captures information on sleep and physical activity for people with smartwatches. The monitor collects, stores, and transmits large datasets which are then remotely analyzed, generating recommendations on possible adjustments to the environment or behavior of the smartwatch users (see infographic below).
Alexandre Affonso / Pesquisa FAPESP
“Having all of this information on a single device is a huge step forward,” says physical educator Marco Túlio de Mello, of the Federal University of Minas Gerais (UFMG), and a specialist in sleep medicine (see Pesquisa FAPESP issue no. 252), who did not take part in the research. “An awareness of oxygen and carbon gas levels is essential for people with respiratory difficulties, in the same way that controlling the temperature is important for those who have thermoregulation issues, such as people who suffer spinal cord injuries. The next step would be to add a way of communicating this environmental information to improve people’s well-being.”
Without leaving her office, architect Daniela Marins, undertaking a postdoctoral fellowship at UFES and leading on development of the prototype, received and analyzed the data collected during two field tests, both run from November 2020 to January 2023 at the Brazilian research Station in Antarctica, and at the Espírito Santo School for Naval Apprentices (EAMES) in the state.
In the first test, after answering questionnaires about their sleep habits, 51 military operatives and researchers wore smartwatches, which released the accumulated data whenever they passed close to three monitors installed on the walls of indoor spaces at the station.
“The station’s laboratory and dormitory windows are very narrow, but those in the main communal space are extremely wide and receive a lot of natural light during summer,” observes Marins, based on the data collected by the monitors and passed on to the station’s coordinators. “They could enjoy the space more not just for meals, but also for meetings and as a communal lounge.”
In the Antarctic, getting good sleep is a privilege. Due to the inclination of the planet’s axis, during the southern hemisphere summer from November to February the sun practically never leaves the sky, and the light is intense, making it difficult to sleep; in the winter, the opposite occurs and darkness pervades throughout almost all of the season, which helps with sleep, but also disrupts it.
Alexandre Affonso / Pesquisa FAPESP
“When we are in Antarctica, we lose our biggest reference: the sun, all track of time, and what time to sleep and wake. Before you know it, it’s nighttime, but because of the light our bodies and brains still think it’s day,” says Federal University of Bahia (UFBA) physical educator Thiago Mendes. He was there in 2020, involved in the scientific research project Mediantar, part of the Brazilian Antarctic Program (PROANTAR) evaluating the effects of extreme environmental conditions on physical and mental health. The researcher accompanied data collection from the Espírito Santo monitor, initially sent to UFES via the 4G network. His plan is to take the new prototypes to Antarctica on his next trip, planned for October, and conduct more comprehensive measurements.
In urban environments distant from the Earth’s extreme south, the excess of artificial light can also adversely affect sleep. According to physician Sérgio Tufik, coordinator of the Institute of Sleep at the Federal University of São Paulo (UNIFESP), who did not participate in the research, greater exposure to light during the night, and less exposure to natural light during the day—common in cities—deregulates production of the hormone melatonin, more intensively in the absence of light, and alters physiological and behavioral processes, including mood (see Pesquisa FAPESP issue no. 313). In an article published in the journal Diagnostics, in January, researchers from Russia’s Tyumen State Medical University observed that the mood and behavior of elderly people improve when adjustments are made to lighting in the environment.
At the naval school EAMES in Greater Vitória, 37 military operatives and professors wore smartwatches connected via Bluetooth to three other monitor prototypes. The records indicated that they slept little and badly in three situations: in March and December, which marked the beginning and end of the educational period, and at weekends, when they left the boarding-school regime and went out for leisure in the city and disrupted their sleep patterns, sleeping more than normal, which is not recommended.
The researchers concluded that in the EAMES building, the problem was restricted light. The construction is a former fortress adapted to function as a school; the walls are thick and the windows small, hampering the entry of natural light. “Small windows are a way of saving on construction materials and facilitating thermal insulation,” says Marins. “The way to reconcile luminosity and temperature would be to redesign the windows using more transparent or light-diffusing materials.”
Sometimes the issue in schools is an excess of light, which reduces concentration and hinders learning. Brazilian legislation stipulates an average beam of 300 lux (a 100-watt incandescent bulb emits equal to 1,500 lux) for classrooms (see infographic above), but a group of researchers from the Federal University of Paraíba (UFPB) recorded more than 2,000 lux in six classrooms across three municipal schools in the state. The results, detailed in November in the journal PARC – Pesquisa em Arquitetura e Construção (Architecture and Construction Research), confirmed the complaints of the 95 students interviewed about the extreme luminosity. “The intensity of natural light cannot be ignored,” stresses Marins.
“The approach of the UFES group may be relevant to quality of life for operatives, students, or researchers in inhospitable locations,” says electrical engineer Antonio Mauricio Ferreira Leite Miranda de Sá, of the Alberto Luiz Coimbra Institute for Engineering Graduate Education and Research at the Federal University of Rio de Janeiro (COPPE-UFRJ), who works in the area but did not participate in the research.
Looking at the configuration of the apparatus, described in the Internet of Things article, he imagines other applications: “It could also be used to record and issue warnings about gas leaks in houses and buildings, or atypical behaviors such as immobility during the day for consecutive hours, primarily people living alone,” he suggests.
The story above was published with the title “Wellness sensors” in issue 351 of May/2025.
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