Perception Of Indoor Environment Research Articles

Combined effects of sound and illuminance on indoor environmental perception

Cross-modal effects of sound and illuminance were investigated in an indoor environmental chamber with 60 university students (30 men and 30 women) aged 18–26 years. A within-subject factorial design was employed with four independent variables: noise level (45, 55, 65, and 75 dBA), noise type (Music, Water, Babble, and Fan), illuminance level (150, 500, and 1000 lx), and sex (female or male). The test conditions represented daily indoor environments, which was moderately noisy and did not present severe lighting conditions. Acoustic (loudness, annoyance, pleasantness, and naturalness) and visual (brightness and relaxation) semantic attributes were assessed using an 11-point numeric scale. The illuminance level of the ambient lighting system did not affect acoustic perception. Brightness was not altered by sound, but relaxation was affected by sound. Cross-modal interactions were asymmetric between sound and illuminance in indoor environmental settings. Women were more sensitive to the perception of both acoustic and illuminance stimuli than men, at high level of stimulation.

Cross-modal effects of noise and thermal conditions on indoor environmental perception and speech recognition

Cross-modal effects of noise and thermal conditions on subjective indoor environmental perception and speech recognition were investigated with 24 native Korean speakers in an indoor environmental chamber. Sixteen combinations of four Predicted Mean Votes (PMV) values (−1.53, 0.03, 1.53, 1.83), two noise levels (45 dBA, 60 dBA) and two noise types (babble, fan) were tested at the noise exposure times of 2 min and 55 min. Speech-to-noise ratios (SNRs) were set to 0, 5 and 10 dB for speech recognition tests based on the presented noise levels. It was found that noise had no effect on thermal sensation and thermal conditions had no effect on loudness and noisiness. However, effects of noise level and type on thermal comfort and effects of PMV on acoustic comfort and annoyance were statistically significant. Thermal comfort decreased with increased noise level. At thermoneutrality, acoustic comfort increased and annoyance decreased. Speech recognition was affected by not only SNR ratio but also by the PMV values according to the room acoustical conditions.

The SMART Study, a Mobile Health and Citizen Science Methodological Platform for Active Living Surveillance, Integrated Knowledge Translation, and Policy Interventions: Longitudinal Study.

BackgroundPhysical inactivity is the fourth leading cause of death worldwide, costing approximately US $67.5 billion per year to health care systems. To curb the physical inactivity pandemic, it is time to move beyond traditional approaches and engage citizens by repurposing sedentary behavior (SB)–enabling ubiquitous tools (eg, smartphones).ObjectiveThe primary objective of the Saskatchewan, let’s move and map our activity (SMART) Study was to develop a mobile and citizen science methodological platform for active living surveillance, knowledge translation, and policy interventions. This methodology paper enumerates the SMART Study platform’s conceptualization, design, implementation, data collection procedures, analytical strategies, and potential for informing policy interventions.MethodsThis longitudinal investigation was designed to engage participants (ie, citizen scientists) in Regina and Saskatoon, Saskatchewan, Canada, in four different seasons across 3 years. In spring 2017, pilot data collection was conducted, where 317 adult citizen scientists (≥18 years) were recruited in person and online. Citizen scientists used a custom-built smartphone app, Ethica (Ethica Data Services Inc), for 8 consecutive days to provide a complex series of objective and subjective data. Citizen scientists answered a succession of validated surveys that were assigned different smartphone triggering mechanisms (eg, user-triggered and schedule-triggered). The validated surveys captured physical activity (PA), SB, motivation, perception of outdoor and indoor environment, and eudaimonic well-being. Ecological momentary assessments were employed on each day to capture not only PA but also physical and social contexts along with barriers and facilitators of PA, as relayed by citizen scientists using geo-coded pictures and audio files. To obtain a comprehensive objective picture of participant location, motion, and compliance, 6 types of sensor-based (eg, global positioning system and accelerometer) data were surveilled for 8 days. Initial descriptive analyses were conducted using geo-coded photographs and audio files.ResultsPictures and audio files (ie, community voices) showed that the barriers and facilitators of active living included intrinsic or extrinsic motivations, social contexts, and outdoor or indoor environment, with pets and favorable urban design featuring as the predominant facilitators, and work-related screen time proving to be the primary barrier.ConclusionsThe preliminary pilot results show the flexibility of the SMART Study surveillance platform in identifying and addressing limitations based on empirical evidence. The results also show the successful implementation of a platform that engages participants to catalyze policy interventions. Although SMART Study is currently geared toward surveillance, using the same platform, active living interventions could be remotely implemented. SMART Study is the first mobile, citizen science surveillance platform utilizing a rigorous, longitudinal, and mixed-methods investigation to temporally capture behavioral data for knowledge translation and policy interventions.

Energy Use and Perceived Indoor Environment in a Swedish Multifamily Building before and after Major Renovation

Improved energy efficiency in the building sector is a central goal in the European Union and renovation of buildings can significantly improve both energy efficiency and indoor environment. This paper studies the perception of indoor environment, modelled indoor climate and heat demand in a building before and after major renovation. The building was constructed in 1961 and renovated in 2014. Insulation of the façade and attic and new windows reduced average U-value from 0.54 to 0.29 W/m2·K. A supply and exhaust ventilation system with heat recovery replaced the old exhaust ventilation. Heat demand was reduced by 44% and maximum supplied heating power was reduced by 38.5%. An on-site questionnaire indicates that perceived thermal comfort improved after the renovation, and the predicted percentage dissatisfied is reduced from 23% to 14% during the heating season. Overall experience with indoor environment is improved. A sensitivity analysis indicates that there is a compromise between thermal comfort and energy use in relation to window solar heat gain, internal heat generation and indoor temperature set point. Higher heat gains, although reducing energy use, can cause problems with high indoor temperatures, and higher indoor temperature might increase thermal comfort during heating season but significantly increases energy use.

PMV와 음환경의 복합 작용이 실내 환경 지각에 미치는 영향

PMV와 음환경의 복합 작용이 실내 환경 지각에 미치는 영향

Perceived Indoor Environment and Occupants' Comfort in European "Modern" Office Buildings: The OFFICAIR Study.

Indoor environmental conditions (thermal, noise, light, and indoor air quality) may affect workers’ comfort, and consequently their health and well-being, as well as their productivity. This study aimed to assess the relations between perceived indoor environment and occupants’ comfort, and to examine the modifying effects of both personal and building characteristics. Within the framework of the European project OFFICAIR, a questionnaire survey was administered to 7441 workers in 167 “modern” office buildings in eight European countries (Finland, France, Greece, Hungary, Italy, The Netherlands, Portugal, and Spain). Occupants assessed indoor environmental quality (IEQ) using both crude IEQ items (satisfaction with thermal comfort, noise, light, and indoor air quality), and detailed items related to indoor environmental parameters (e.g., too hot/cold temperature, humid/dry air, noise inside/outside, natural/artificial light, odor) of their office environment. Ordinal logistic regression analyses were performed to assess the relations between perceived IEQ and occupants’ comfort. The highest association with occupants’ overall comfort was found for “noise”, followed by “air quality”, “light” and “thermal” satisfaction. Analysis of detailed parameters revealed that “noise inside the buildings” was highly associated with occupants’ overall comfort. “Layout of the offices” was the next parameter highly associated with overall comfort. The relations between IEQ and comfort differed by personal characteristics (gender, age, and the Effort Reward Imbalance index), and building characteristics (office type and building’s location). Workplace design should take into account both occupant and the building characteristics in order to provide healthier and more comfortable conditions to their occupants.

Self-reported health and comfort in 'modern' office buildings: first results from the European OFFICAIR study.

In the European research project OFFICAIR, a procedure was developed to determine associations between characteristics of European offices and health and comfort of office workers, through a checklist and a self-administered questionnaire including environmental, physiological, psychological, and social aspects. This procedure was applied in 167 office buildings in eight European countries (Portugal, Spain, Italy, Greece, France, Hungary, the Netherlands, and Finland) during the winter of 2011-2012. About 26735 survey invitation e-mails were sent, and 7441 office workers were included in the survey. Among respondents who rated an overall comfort less than 4 (23%), 'noise (other than from building systems)', air 'too dry', and temperature 'too variable' were the main complaints selected. An increase of perceived control over indoor climate was positively associated with the perceived indoor environment quality. Almost one-third of office workers suffered from dry eyes and headache in the last 4weeks. Physical building characteristics were associated with occupants' overall satisfaction (acoustical solutions, mold growth, complaints procedure, cleaning activities) and health (number of occupants, lack of operable windows, presence of carpet and cleaning activities). OFFICAIR project provides a useful database to identify stressors related to indoor environmental quality and office worker's health.

User's perception of indoor environment associated with energy performance in apartment complexes with different service life

Residents’ illnesses related to new houses have recently become a popular topic for Sick Building Syndrome research. Compared to the research dealing with symptoms experienced by residents in newly built houses, little attention has been paid to the healthy life of residents in old houses. Thus, we investigate residents’ experience of healthy life in two apartment complexes that have been in service for different amounts of time and ascertain whether any difference exists between them. It is generally believed that the energy efficiency of old apartments has decreased, and thus residents’ comfort and health in such apartments would deteriorate according to the apartments’ service life. This study aims to obtain an insight into residents’ perceived experience in older apartments. We use three survey methods for the investigation and analyze the data from the residents’ perspective. The results show that the physical properties of the apartments do not have much influence on the residents’ perceived comfort and health; further, energy efficiency does not affect their perceived comfort and health either. The critical influencing factor for residents’ discomfort is the indoor temperature, not any of the other physical conditions of the apartments.

Satisfaction Perception of Indoor Environment of Low-cost Housing: A case study of Flat Taman Desa Sentosa

Low-Cost Flat Housing is the housing for low income group.. It began with a flat which has two bedrooms in each unit, then it was increased three bedrooms. The three bedrooms flat has to fit the floor area of 650 square feet, in which was later revised to 700 square feet. Small overall floor area which comes with small budget allocated for its construction, could lead to poor indoor environmental quality (IEQ) in low-cost flat, if not properly designed. This paper discusses on the occupants’ satisfaction perception of IEQ of a low cost flat in Kampung Teras Jernang, Selangor. The methodologies used in this study are site observation and questionnaire survey. This study concludes that the IEQ in the selected low-cost flat has acceptably fulfilled the needs and quality required by the occupants. However, there is a factor that the building occupants have expressed poor perception, which is the noise pollution.

울산지역의 대기오염 환경의 차이가 거주자의 실내환경 평가 및 인식에 미치는 영향

The aim of this study was to evaluate the influence of air pollution level in industrial and residential district of Ulsan on resident`s evaluation and cognition for indoor environment. The evaluation of air pollution materials (as , , , CO, PM10) were investigated to understand the distributional characteristics in survey area, and air quality monitoring data from 2007 to 2009 were used. The data was applied in a realtime measurement of industrial and residential area respected to difference of the pollution level in Ulsan. The questionnaire of this survey for resident`s cognition was to find out characteristics on perception of indoor environment and outdoor air quality recognition based on the distinct characteristics of the areas. The results of this study shows that resident`s satisfaction at clean level outdoor air and indoor environment were different whether it was residential area or industrial area and outdoor air pollution level has direct influence on resident`s satisfaction in indoor environment.

Occupants’ evaluation of indoor environment, energy usage and controls of office buildings in Kumasi (Ghana)

A study was conducted to evaluate occupants’ perception of indoor environment, operation and functionality of building control systems, and energy implications of user behaviour towards the improvement of building desig-ns. Over a period of 12 months, data loggers were installed in 5 office buildings in Kumasi (Ghana) to record temperature and relative humidity values. In addition, a comprehensive questionnaire was administered to 64 occupants. The data and responses were evaluated and analysed by MS Excel. The outcomes showed that 45 % of occupants in mixed-mode and 70 % in naturally ventilated buildings were uncomfortable with the air quality during the dry season. The highest dissatisfaction with indoor environment was reported by 85 % of occupants in naturally ventilated building. The importance attached to operating windows and shades was relatively high-er (80 %) in the mixed-mode and naturally ventilated buildings than in the air-conditioned types (55 %). Train-ing in operation and functionality of control systems was identified as key factor affecting energy performance of the office buildings. Attention to building control systems, user perceptions and behaviour could improve the design, quality and energy performance of office buildings.

Energy efficiency and indoor thermal perception: a comparative study between radiant panel and portable convective heaters

This study investigates experimentally the thermal perception of indoor environment for evaluating the ability of radiant panel heaters to produce thermal comfort for space occupants as well as the energy consumption in comparison with conventional portable natural convective heaters. The thermal perception results show that, compared with conventional convection heater, a radiantly heated office room maintains a lower ambient air temperature while providing equal levels of thermal perception on the thermal dummy head as the convective heater and saves up to 39.1% of the energy consumption per day. However, for human subjects’ vote experiments, the results show that for an environmentally controlled test room at outdoor environment temperatures of 0°C and 5°C, using two radiant panel heaters with a total capacity of 580 W leads to a better comfort sensation than the conventional portable natural convective heater with a 670 W capacity, with an energy saving of about 13.4%. In addition, for an outdoor environment temperature of 10°C, using one radiant panel heater with a capacity of 290 W leads to a better comfort sensation than the conventional convection heater with a 670 W capacity, with an energy saving of about 56.7%. From the analytical results, it is found that distributing the radiant panel heater inside the office room, one on the wall facing the window and the other on the wall close to the window, provides the best operative temperature distribution within the room.

An experimental study on effects of increased ventilation flow on students perception of indoor environment in computer classrooms

The effects of ventilation in computer classrooms were studied with university students (n = 355) in a blinded study, 31% were women and 3.8% had asthma. Two classrooms had a higher air exchange (4.1-5.2 ac/h); two others had a lower air exchange (2.3-2.6 ac/h). After 1 week, ventilation conditions were shifted. The students reported environmental perceptions during the last hour. Room temperature, RH, CO2, PM10 and ultra-fine particles were measured simultaneously. Mean CO2 was 1185 ppm at lower and 922 ppm at higher air exchange. Mean temperature was 23.2 degrees C at lower and 22.1 degrees C at higher air exchange. After mutual adjustment (temperature, RH, CO2, air exchange), measured temperature was associated with a perception of higher temperature (P < 0.001), lower air movement (P < 0.001), and poorer air quality (P < 0.001). Higher air exchange was associated with a perception of lower temperature (P < 0.001), higher air movement (P = 0.001), and better air quality (P < 0.001). In the longitudinal analysis (n = 83), increased air exchange caused a perception of lower temperature (P = 0.002), higher air movement (P < 0.001), better air quality (P = 0.001), and less odor (P = 0.02). In conclusion, computer classrooms have CO2 levels above 1000 ppm and temperatures above 22 degrees C. Increased ventilation from 7 l/s per person to 10-13 l/s per person can improve thermal comfort and air quality. Computer classrooms are crowded indoor environments with a high thermal load from both students and computer equipment. It is important to control room temperature either by air conditioning, sun shields, or sufficiently high ventilation flow. A high ventilation flow is also crucial to achieving good perceived air quality. Personal ventilation flow should be at least 10 l/s. Possible loss of learning ability due to poor indoor air quality in university buildings deserves more attention.

Structural equation analysis of the causal relationship between health and perceived indoor environment

To explore the temporal relationship and reversed effects between health and perception of the indoor environment using structural equation models. The study was a two-phase prospective questionnaire study with a cross-lagged design. Altogether 1,740 adults participated on both occasions. The perceived indoor environment had only weak effects on health at follow-up. However, the results strongly indicated a reversed effect that health problems may lead to increased complaints about the indoor environment. Structural equation models are powerful analytical tools for disentangling the effects of a specific variable on another in high dimensional data with complex patterns of associations. The analyses confirmed the results of our previous logistic regression analysis about the strong reversed effect. Hence, it is probable that a reversed effect between health and complaints about the indoor environment exists.

The sick building syndrome: a chicken and egg situation?

To examine the temporal relationship and specificity between self-reports on the indoor environment at work and symptoms that are traditionally connected with the sick building syndrome (SBS). This questionnaire study used a prospective full panel design as regards self-reports on exposure and outcome. At the baseline, the sample comprised 2,164 adults selected randomly from the general population. Of these 1,402, who were still working and living in the same place, completed a second questionnaire a year later. Health measures were symptoms that are traditionally connected with the SBS, as well as some "dummy" symptoms that hardly can be causally related to the indoor environment. The associations between self-reports on the indoor environment and these symptom groups were assessed both in cross-sectional and longitudinal analyses, the latter examining the normal direction that exposure leads to symptoms as well as the reverse order: that symptoms lead to perceived exposure. In cross-sectional analyses, the indoor environment factors were associated equally with SBS symptoms and with "dummy" symptoms. In longitudinal analyses, only few of the indoor environment factors predicted the development of any of the symptom groups. However, both the SBS symptoms and the "dummy" symptoms were risk factors for beginning to report exposures in the indoor environment. Symptoms predict future reports on exposures in the indoor environment indicating that it is difficult to determine what existed first: the outcome or the exposure. In addition, the perceived indoor environment is associated not only with the traditional SBS symptoms, but also with symptoms that cannot be physiologically linked to the indoor environment. These results suggest that there is a risk of reporting bias when assessing non-specific symptoms. Thus, many of the associations found in previous cross-sectional studies on SBS symptoms and indoor environment factors may possibly be explained by reporting bias.

Seasonal variation in perceived indoor environment and nonspecific symptoms in a temperate climate.

Few epidemiological studies have examined the effects of season on symptoms typical of sick building syndrome (SBS). The present study aims to clarify seasonal variation in a perceived indoor environment and SBS symptoms in a temperate climate. A total of 116 workers were recruited from office buildings in southern Japan that presented no apparent serious indoor problems. A validated questionnaire was distributed four times, once at the end of each season. Seasonal effects on the perceived indoor environment and SBS symptoms were investigated with a parametric test for repeated measurement of categorical data. Logits were used as the response function, and were compared to overall logits to determine the relevant odds ratios (OR). The effect of season/building interaction was also evaluated. Significant seasonal variation in the perceived indoor environment was found for temperature, dryness, air stuffiness, and static electricity (p for season, <0.05), although the seasonal patterns for temperature and dryness differed according to the building (p for interaction, <0.05). Symptoms in the mucous membrane (eyes, nose, and throat) and skin increased considerably in the winter and spring (p for season, <0.05), whereas general symptoms varied little, but such seasonality of symptoms was not modified by the building factor. The associations between perception of indoor environments and mucous and skin symptoms became stronger during winter and spring. The present results suggest that perceived indoor environments, nonspecific symptoms and their associations are closely associated with the season among office workers in a temperate climate.

Differences in perception of indoor environment between Japanese and non-Japanese workers

Field surveys were conducted at an office with multinational workers in Japan to investigate the differences in the way groups of occupants perceive the environment under real working conditions. Returned questionnaires, 406 in total, were classified into three groups according to their nationality and sex. Only 26% of workers reported their working environment to be comfortable. A significant neutral temperature difference of 3.1 °C was observed between the Japanese female group and the non-Japanese male group under their usual working conditions. Japanese females reported a higher frequency of sick building syndrome related symptoms compared to other groups. Occupant comfort and reported frequency of SBS symptoms were closely related to deviation of the thermal sensation vote from neutral. The thermal environment was found to be a major factor affecting occupant comfort in the concerned office. Differences in the perception of the indoor environment were negatively affecting the ratings of their working environment.