Occupant satisfaction survey as a tool to improve IEQ: a case-study in a
hospital
Kirsi Villberg1,*, Maija Virta1 , Mervi Kajaala1 and Marianna Tuomainen2
1
2
Halton Oy, Finland
Public Works Department, Helsinki, Finland
*
Corresponding email: kirsi.villberg@halton.com
SUMMARY
In this study, an occupant satisfaction survey and audit were carried out in a hospital. The
results show that the occupants have suffered from poor indoor air quality and a wide variety
of symptoms such as nose symptoms (stuffy nose and sneezing), eye symptoms and throat
symptoms (hoarseness). The results also showed that the respondents were very dissatisfied
with thermal comfort (68 % dissatisfied) and indoor air quality (82 % dissatisfied). Also, the
occupants reported on unpleasant odours. In auditing the site it was found out that one reason
for the eye symptoms and hoarseness was particle emissions from uncoated mineral wool
acoustic panels in suspended ceilings. These mineral wool fibres are known to cause irritation
in the upper respiratory tracts and are suspected to cause health problems among occupants.
The main reason for complaints on thermal comfort was very high room air temperature in
summertime and draught from windows in wintertime. Also, the over-pressurized room
spaces caused inadequate ventilation efficiency and complaints on IAQ.
KEYWORDS
User- focused survey, Indoor Environment Quality (IEQ), symptoms, hospital environment,
particle emission
INTRODUCTION
There is a wide variety of problems related to the indoor environment. Often it is quite
difficult to locate the problem source in a large building, e.g. a hospital. There are many floors
and wings in the buildings and different usage of spaces, etc. A user-focused survey is an
effective way to characterise perceived indoor air quality and user satisfaction. This kind of an
occupant satisfaction survey helps to identify and locate indoor environment related problems,
such as the lack of acoustic planning, lack of ventilation, draught, and the prevalence of
building related symptoms.
The most common symptoms reported in office buildings and among hospital workers are
nose, eye and throat symptoms. Nose symptoms consist basically of rhinitis, stuffy nose,
irritation, phlegm and also sinusitis. Definitions such as stinging, scratching, burning and
itching are also used (Kendall-Reed, et al. 2001). Eye symptoms such as ocular irritation,
burning of eyes and dry eyes and throat symptoms such as hoarseness and dyspnoea are also
building-related symptoms. In addition, skin irritation, neurotoxic symptoms, unspecified
hypersensitivity, unpleasant odour, headache, fatigue and insomnia are reported (Bayer and
Crow 1993).
Nowadays these above mentioned complaints concerning building related symptoms are
increasing rapidly. The symptoms may be caused by volatile organic compounds (VOCs)
which are formed and emitted by dampness causing material degradations. For example, for
flooring materials typical degradation emissions are VOCs such as 2-ethyl-1-hexanol. Some
typical compounds or even chemical groups are known to be responsible for fungal odours,
thus these compounds could be directly associated to microbial growth. It is known that the
microbiological contaminants emit volatile organic compounds; microbial origin VOCs
(MVOCs). One cause for rashes and respiratory illnesses could be these MVOCs. Some
MVOCs may be identified in indoor air like foul, fungal smelly odour caused by geosmin and
2-methyl-isoborneol. Usually these compounds are not building material based (Bayer and
Crow 1993; Norbäck 1995;Wieslander 1997,2007; Kim et al. 2007).
The interpretation may sometimes be difficult, because some MVOCs are the same as VOCs
emitted typically from building or finishing materials e.g. eye symptoms and asthma are
caused by one VOC compound emitted from plastic flooring material without any dampness
(Villberg 2008; Wieslander 1997). However, an exact correlation between symptoms and
their sources is usually difficult to make.
There are many types of questionnaires to use for surveying occupant satisfaction and
building related symptoms (Andersson et al. 1993; Engvall et al. 2004; Mendell 2005,
Susitaival et al 1996; Takki and Virta 2007; Villberg 2002; Zagreus et al. 2004). Usually the
questionnaires include questions on symptoms, satisfaction with thermal conditions and
ventilation and the background of the user (previous doctor-diagnosed asthma, current
medication, other illnesses). All occupants in the building or office space are given the
possibility to respond to the survey and describe their indoor environment.
METHODS
When using a user-focused survey, it is easy to locate indoor environment related problems to
a specific space of the building. The survey results clearly pinpoint areas with excessive
number of dissatisfied users and define the sources of the problems. When these survey results
are filtered through floors and wings, different symptoms may be located to different parts of
the building. After this kind of a survey, as a part of the systematic process, an audit is carried
out where other technical faults such as lack of acoustic planning, lack of ventilation and
draught are analyzed.
In a Finnish hospital the users had been suffering from different symptoms. The hospital is
large and consists of two buildings A and C. Building C consists mainly of sickrooms and
administrational spaces. Building A consists mainly of office and practise rooms. (Figure 1)
Figure 1. Hospital building.
Occupant survey
It would have been difficult to focus proper investigations on different parts of the building
immediately. The occupation satisfaction survey was conducted at the beginning of the
project. Questions focused on the respondents personal experience of the indoor environment
and additionally building related symptoms. If the respondent was dissatisfied with a specific
area of indoor environment, more specific additional questions were asked concerning the
extent of the problem and its possible causes. Most of the questions were answered by
choosing from among predetermined options.
Based on the feedback, an Indoorium Perception Map™ (Takki and Virta 2007) of the
reported symptoms was created to identify and locate problems and symptoms. An action plan
to improve the indoor environment quality and occupant satisfaction was drawn up based on
the survey results. In addition, the survey results acted as an argument for the decision makers
that measures to improve indoor environment conditions must be taken.
Auditing
After the survey a special diagnose was conducted to analyse in more detail the cause of
dissatisfaction and symptoms. This diagnose was conducted almost in all building parts since
dissatisfaction was quite high all over the buildings. The diagnose included sensory auditing,
air volume measurements, temperature measurements, smoke visualization and interviews.
The diagnose was performed in a couple of representative spaces of each audited part of the
buildings.
RESULTS
Dissatisfaction towards thermal comfort (68 %) and air quality (82 %) was very high.
Dissatisfaction with thermal comfort varied from 29 % to 90 % and with air quality from 38
% to 100 % in different areas of the buildings. The perception map of the reported symptoms
revealed in which areas of the hospital the problems were concentrated (Table 1).
Reported symptoms
Over 20 % of the respondents suffered from respiratory symptoms (hoarse, dry throat), nose
symptoms (irritated stuffy of runny nose) and eye symptoms (itching, burning or irritation of
the eyes).
Table 1. Perception map of reported symptoms
Building A
South
South
wing
wing
2nd
3rd
12
13
92 %
62 %
42 %
0%
33 %
15 %
17 %
8%
17 %
0%
42 %
8%
33 %
15 %
33 %
23 %
8%
0%
17 %
0%
25 %
8%
50 %
8%
8%
0%
17 %
0%
17 %
0%
17 %
0%
25 %
0%
0%
0%
South
All ( A ) wing
Percentage of people that have symptoms
weekly
1st floor
Persons
98
40
Suffers from indoor environment related symptoms 65 %
68 %
Fatigue
27 %
33 %
Feeling heavy-headed
19 %
25 %
Headache
13 %
20 %
Difficulties concentrating'
10 %
13 %
Itching, burning or irritation of the eyes
24 %
30 %
Irritated stuffy or runny nose
34 %
43 %
Hoarse, dry throat
27 %
30 %
Cough
7%
10 %
Cough disturbing sleep
3%
0%
Dry or flushed facial skin
15 %
15 %
Hands dry, itching, red skin
24 %
28 %
Dyspnoea (shortness of breath)
3%
3%
Wheezing
3%
0%
Fever or chill
3%
3%
Joint ache or stiffness
6%
3%
Muscle pain
7%
3%
Other
1%
3%
Building C
North
South
North
wing All ( C )
wing
wing
1st floor
16
73
52
30
31 %
77 %
73 %
60 %
6%
34 %
35 %
23 %
0%
27 %
29 %
17 %
0%
21 %
21 %
13 %
0%
18 %
21 %
7%
19 %
37 %
40 %
20 %
6%
48 %
50 %
30 %
6%
34 %
35 %
23 %
0%
14 %
8%
20 %
0%
1%
0%
3%
6%
26 %
21 %
27 %
6%
30 %
29 %
23 %
0%
3%
0%
7%
0%
3%
0%
7%
0%
7%
10 %
0%
0%
10 %
12 %
3%
0%
8%
10 %
3%
0%
3%
2%
3%
Thermal comfort
68 % of the respondents were dissatisfied with thermal comfort. The main reasons were the
room temperature being often too hot (57 % of all respondents) during warm/hot weather and
the room temperature being often too cold (55 % of all respondents) during cool/cold weather.
Another reason for users’ complaints was that the temperature varied during the day.
Temperature in the workspace in warm/hot
weather
0%
13 %
Varies
5%
4%
Suitable
55 %
Often too cold
2%
Varies
16 %
Often too hot
57 %
Often too hot
Often too cold
Temperature in the workspace in cool/cold
weather
5%
Suitable
20 %
40 %
60 %
80 %
Percentage of all respondents
100 %
0%
20 %
40 %
60 %
80 %
100 %
Percentage of all respondents
Figure 2. Reasons for dissatisfaction a) in hot/cold weather, b) in cool/cold weather.
Air quality and odours
The main reason for dissatisfaction was poor air quality. Respondents reported that indoor air
is stuffy or stale (67 % of respondents). 15 % of the respondents described that the air is not
clean and 37 % of the respondents reported that odours and scents were disturbing.
Air quality - cause of dissatisfaction
37 %
Odours and scents disturb me
15 %
Air is not clean
67 %
Air is stuffy/stale
16 %
Other
0%
20 %
40 %
60 %
80 %
100 %
Percentge of all respondents
Figure 3. Air quality causes of dissatisfaction.
Auditing
When auditing the site it was found out that one reason for eye symptoms and hoarseness was
particle emissions from uncoated mineral wool acoustic panels in suspended ceilings. These
mineral wool fibres are known to cause irritation in upper respiratory tracts and were
suspected to cause health problems among occupants.
The main reason for complaints on thermal comfort was very high room air temperature in
summertime and draught from windows in wintertime. Supply air is cooled only in some parts
of the building but the cooling is not adequate since the temperature rises above 28-Celsius
degrees. In the parts that have no cooling the temperature rises above 30-Celsius degrees,
which much higher than any recommendations indicate. Because of high room temperatures,
occupants tend to use table fans and ventilate through windows, which also causes draft.
Reasons for dissatisfaction with air quality were inadequate airflow rates and an air
distribution strategy that leads to fresh air not entering into the occupied zone. Odours from
sickrooms also generated dissatisfaction. Sickrooms were mostly over-pressurized which
caused air flowing from sickrooms to other spaces, e.g. corridors.
DISCUSSION
Good indoor air and environmental quality are very important especially in hospitals.
Different symptoms and fungal or material-based odours were reported in this study. Damp
buildings are known to correlate with different symptoms. Many types of questionnaire
studies are widely used to point out IAQ problems. When indoor environment-related
problems appear, an effective tool to solve these problems is needed.
Using a comprehensive study that includes both survey and audit different kinds of problems
that cause dissatisfaction and symptoms can be discovered. Before this study was conducted it
was assumed that the cause for the symptoms was mould in the structures of the hospital
buildings. However, it was found out that there were several reasons behind the symptoms
and complaints. For example, very high room temperature can cause e.g. fatigue, headache
and nausea.
CONCLUSIONS
Abovementioned problems and building related symptoms are easily identified and located
when using a user-focused satisfaction survey. Because of its effectiveness, it seems to be a
cost and time saving tool to improve indoor environment quality.
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