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Gender Differences in Perception of Indoor Environmental Quality (IEQ)
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WMCAUS 2019
IOP Conf. Series: Materials Science and Engineering 603 (2019) 052084
IOP Publishing
doi:10.1088/1757-899X/603/5/052084
1
Gender Differences in Perception of Indoor Environmental
Quality (IEQ)
Michal Kraus1
, Petra Novakova1
1
Institute of Technology and Business in České Budějovice, Department of Civil
Engineering, Okružní 517/10, 370 01 České Budějovice, Czech Republic
info@krausmichal.cz
Abstract. There are many factors creating the internal environment of the building. These factors
could be biological, physical, or chemical, and they determine the indoor environmental quality.
This contribution investigates the gender differences in occupants' perception on various aspects
of indoor environmental quality (IEQ). There are many studies, how the conditions of the indoor
environment affect the users' performance, health, or comfort. Generally, women are more likely
to have symptoms of SBS, such as fatigue, headache, irritated or dry eyes, nose and throat, and
skin symptoms. Assessments of user´s perception were carried out at the Institute of Technology
and Business situated in the city of České Budějovice, South Bohemia, Czechia. The panellists
(students) indicated their immediate evaluation on eight continuous scales regarding air
acceptability, odor intensity, thermal comfort, humidity comfort, visual comfort, color comfort,
noise load and total satisfaction. Then the percentage of dissatisfied people (PN) was estimated.
The gender differences in perception of indoor environmental quality were analysed. This
knowledge is necessary and useful to develop appropriate strategies to create and maintain a
sustainable internal environment for education and training. Understanding the perception of the
quality of the inner environment by students is essential to increase the performance and
productivity of not only students but also the academic staff. The long-term low indoor
environment quality can lead to poor productivity, performance and ability to learn. It is also
necessary to take into account the health of students and also academic staff in the context of the
hygiene of the internal environment.
1. Introduction
In urbanized and industrialized areas, people spend up to 90% of their time indoors [1]. It is clear that
the quality of life is determined by the quality of the indoor environment. The indoor environmental
quality (IEQ) is defined by a number of factors. These factors could be biological, physical, or chemical
[2]. Indoor environmental quality evaluates the entire indoor environment of buildings. This includes
all factors that affect occupants’ health, comfort and well-being [3]. There are a number of studies aimed
at evaluating the quality of the indoor environment with regard to comfort and health [4-7]. Strategies
for addressing IEQ include those that protect human health, improve quality of life (well-being), and
reduce potential risks and pollution. Exposure to pollutants in the air may provide a certain health risk.
The long-term unsatisfactory indoor environment is associated with Sick Building Syndrome (SBS).
Understanding the perception of the quality of the indoor environment by students is essential to increase
the performance and productivity of not only students but also the academic staff. The long-term low
indoor environment quality can lead to poor productivity, performance and ability to learn. The best
WMCAUS 2019
IOP Conf. Series: Materials Science and Engineering 603 (2019) 052084
IOP Publishing
doi:10.1088/1757-899X/603/5/052084
2
way to ensure a suitable indoor environment is to eliminate or at least minimize pollutant resources and
manage their distribution. In addition to the building materials themselves, electrical appliances are also
a source of pollutants (VOCs, odors) [8].
The general assumption is that women are more sensitive to the colder thermal environment than
men. Men get morphologically different from women. Men are characterized by greater average body
weight, greater musculature, and a higher skin area to weight ratio [9, 10]. Gender-related differences
in body morphology affect the thermoregulation processes and perceived quality of the environment.
Generally, women are more likely to have symptoms of SBS, such as fatigue, headache, irritated or dry
eyes, nose and throat, and skin symptoms.
2. Method
Assessments of user´s perception were carried out at the Institute of Technology and Business situated
in the city of České Budějovice, South Bohemia, Czechia. Ten different university classrooms are
selected for sensory assessment of indoor environmental quality. Two of the observed university
classrooms are computer classrooms. Two classrooms serve as lecture halls for more than 200 listeners.
One of them is equipped with a forced ventilation system. One classroom serves as a laboratory. The
walls and ceilings are fitted with a classic internal plaster with white paint. Flooring is synthetic smooth
flooring - linoleum. The windows are new, plastic with a shading system of internal blinds. The
classroom equipment is classical and includes tables, chairs, whiteboard, computer and projector.
Measurements took place in October under favourable climatic conditions. During the measurements,
the mean outdoor air temperature is 15.86°C and the mean outdoor relative humidity is 63.74%. The
mean outdoor concentration of CO2 is 645 ppm.
Before the assessment, the students were instructed on to using the scales. There is no restriction on
the distribution of gender or smoking habits. The age ranged from 20 to 25 years. All panellists are
university students. Overall, 299 students were interviewed. The panellists are dominated by men (246;
82%). The small proportion of women (53; 18%) is due to the common composition of students in
technical fields (Civil Engineering).
The panellists stay outdoor odors before the assessments. Before the lesson, the panellists indicated
their immediate evaluation on eight continuous scales regarding air acceptability (AA), odor intensity
(OI), thermal comfort (TC), humidity comfort (HC), visual comfort (VC), color comfort (CC), noise
load (NL) and total satisfaction (TS). The scale of air acceptability is divided into 2 separates scales with
end-point clearly acceptable (+1) / just acceptable (0) and just unacceptable (0) /clearly unacceptable (-
1). The scale of odor intensity has five levels of intensity odor: 0 no odor, 1 slight odor, 2 moderate
odor, 3 strong odor, 4 very strong odor and 5 overwhelming odor. According to ASHRAE the scale of
thermal comfort has 7 levels: +3 hot, +2 warm, +1 slightly warm, 0 neutral, -1 slightly cool, -2 cool, - 3
cold. The humidity scale has five levels: 2+ too humid, +1 slightly humid, 0 just right, -1 slightly dry
and -2 too dry. The range of perceived visual levels has five levels: +2 too bright, +1 slightly bright, 0
just right, -1 slightly dark and -2 too dark. The noise load scale is divided into five levels: 1 no noise, 2
slight noise, 3 acceptable noise, 4 strong noise and 5 intolerable noise. The scale of perceived colors
applied in the interior has 5 levels: +2 too high, +1 high, 0 just right, -1 low, -2 too low. The scale of
overall satisfaction includes 5 levels: +2 too high, +1 high, 0 just right, -1 low, -2 too low. The limit
answers (maximum values of each scale) are regarded as discomforts in this study. Then the percentage
of dissatisfied (PN) was estimated.
3. Results and discussions
The satisfaction levels of perceived quality by gender is shown in figure 1, where AA is air acceptability,
OI is odor intensity, TC is thermal comfort, HC is humidity comfort, VC is visual comfort, CC is color
comfort, NL is noise load and TS is total satisfaction. According to constructed boxplots, the perceived
WMCAUS 2019
IOP Conf. Series: Materials Science and Engineering 603 (2019) 052084
IOP Publishing
doi:10.1088/1757-899X/603/5/052084
3
quality of indoor environment parameters is comparable without major differences between men and
women. For better clarity, mean values of perceived quality of IEQ parameters and percentage of
dissatisfied (PN) are considered.
Figure 1. Perceived indoor environmental quality by gender
3.1. Mean satisfaction level
Figure 2 shows the mean satisfaction rating for monitored parameters of indoor environmental quality
by gender. Mean satisfaction rating of indoor environment parameters by gender are also included in
table 1.
Figure 2. Mean satisfaction rating of indoor environment parameters by gender
WMCAUS 2019
IOP Conf. Series: Materials Science and Engineering 603 (2019) 052084
IOP Publishing
doi:10.1088/1757-899X/603/5/052084
4
Gender differences in perceived quality in terms of air acceptability, humidity comfort, color comfort
and overall satisfaction are minimal. The mean values of thermal comfort show that women perceive
the indoor environment as cooler than perceived comfort for men. Men have a negative perception of
visual comfort, while for women, visual comfort is still acceptable. The perceived color of the interior
is negatively evaluated by both men and women. The mean values of odor intensity indicate slight odor.
Men perceive odors more sensitively than women. Conversely, the noise load is more acceptable to men.
The mean values of total satisfaction are positive. The quality of the indoor environment is acceptable
for both men and women.
Table 1. Mean satisfaction rating of indoor environment parameters by gender
AA TC HC VC CC OI NL TS
Gender
Women 0.274 0.500 -0.100 0.250 -0.080 0.980 1.480 0.330
Men 0.233 0.810 -0.040 -0.080 -0.100 1.170 1.280 0.290
∆ 0.041 -0.310 -0.060 0.330 0.020 -0.190 0.200 0.040
Legend: air acceptability (AA), odor intensity (OI), thermal comfort (TC), humidity comfort (HC), visual comfort (VC), color
comfort (CC), noise load (NL) and total satisfaction (TS)
3.2. Percentage dissatisfied with the indoor environmental quality
Percentage of dissatisfied is widely regarded as a meaningful and practical metric in perceived indoor
environmental quality because it can be readily interpreted as an expression of the number of potential
dissatisfactions. Percentages dissatisfied of indoor environment parameters by gender are illustrated in
figure 3. Table 2 expresses percentages dissatisfied by gender.
Four of the eight observed indoor environmental quality factors express greater dissatisfaction among
women. These are humidity comfort, visual comfort, color comfort and total satisfaction. Other factors
are dominated by dissatisfaction among men. Women are most dissatisfied with visual comfort (9.43%)
and humidity comfort (7.55%). Also, men are significantly dissatisfied with visual comfort (4.88%).
Furthermore, they are significantly dissatisfied with color comfort (4.88%) and humidity comfort and
thermal comfort. The smallest values of dissatisfaction are monitored for the air acceptability and noise
load.
Figure 3. Percentage dissatisfied of indoor environment parameters by gender
WMCAUS 2019
IOP Conf. Series: Materials Science and Engineering 603 (2019) 052084
IOP Publishing
doi:10.1088/1757-899X/603/5/052084
5
Table 2. Percentage dissatisfied with the IEQ factors by gender
AA TC HC VC CC OI NL TS
Gender
Women 0.00% 3.78% 7.55% 9.43% 5.66% 0.00% 0.00% 1.89%
Men 1.63% 4.07 % 4.07% 4.88% 4.88% 2.03% 0.81% 1.22%
Legend: air acceptability (AA), odor intensity (OI), thermal comfort (TC), humidity comfort (HC), visual comfort (VC), color
comfort (CC), noise load (NL) and total satisfaction (TS)
3.3. Correlation between gender and IEQ parameters
The correlation determines the relationship of dependence of two continuous random variables. Two
random variables correlate if certain values of one variable tend to co-occur jointly with certain values
of the other variable. The relationship between two continuous random variables X and Y with unknown
distribution can be expressed using the Spearman correlation coefficient [11, 12]. The Spearman
correlation coefficient is a nonparametric correlation coefficient that is robust to outliers and generally
deviates from normality, because like many other nonparametric methods it only works with the order
of observation. Unlike the Pearson correlation coefficient, which describes the linear relationship of
variables, the Spearman correlation coefficient describes how well the relationship values corresponding
with the monotonic function, which may of course be non-linear.
IBM SPSS statistics version 25 was used to analyse the data. Table 3 shows the results of Spearman's
Rank-Order Correlations between gender and IEQ parameters. Statistically significant correlation at 5%
significance level was not found in any of the monitored internal environment parameters. The perceived
quality of the indoor environment is not affected by gender.
Table 3. Spearman's Rank-Order Correlations between gender and IEQ parameters
AA TC HC VC CC OI NL TS
Gender
Correlation Coefficient 0.003 0.092 0.047 -0.102 -0.030 0.073 -0.102 0.002
Sig. (2-tailed) 0.956 0.110 0.422 0.078 0.601 0.209 0.079 0.970
N 299 299 299 299 299 299 299 299
Legend: air acceptability (AA), odor intensity (OI), thermal comfort (TC), humidity comfort (HC), visual comfort (VC), color
comfort (CC), noise load (NL) and total satisfaction (TS)
4. Conclusions
The goal of sustainable construction is energy efficiency, environmental friendliness and sustainability.
Green sustainable buildings provide better indoor environments with less energy consumptions and it
has achieved a vigorous growth in recent years. It is essential that building users are satisfied in their
indoor environment. Since students spend quality time in school trying to learn, it is important to study
the effects of their classroom environment on their health and performance. It is generally known that
women are more sensitive to the perceived quality of the indoor environment. However, this fact has
not been proven in the study. Based on the results of this study, the results of the correlation analysis
show that there is no statistical relationship between gender and internal environment factors such as
temperature, humidity, noise, air acceptance, odors, visual comfort and color of indoors.
Acknowledgment(s)
The contribution is supported by the Specific University Research SVV 201802 Address identification
and analysis of the determinants of the Indoor Environment Quality (IEQ).
WMCAUS 2019
IOP Conf. Series: Materials Science and Engineering 603 (2019) 052084
IOP Publishing
doi:10.1088/1757-899X/603/5/052084
6
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