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Hospital staff's preferences for daylighting to notions of the effects of daylight on patient's recovery times and processes, their experiences of daylight when treating and diagnosing patients and patient comfort levels is studied. A questionnaire survey was developed as a tool to review subjective judgments of the staff lighting needs and satisfaction. Responses obtained from one hundred and thirty four staff showed that seventy nine percent of the participants identify daylight in patient's room as a factor helping them do their work more easily, and Seventy seven percent of the surveyed nurses and doctors claimed that daylight is an important element in patient rooms to aid in reviewing patient recovery through recognizing and interpreting changes in patient skin color. Seventy eight percent of hospital nurses and all the surveyed doctors believe that daylight has many health benefits including fast recovery and reduced length of stay for patients. Moreover, ninety two percent of the surveyed staff stated that patients preferred to stay in rooms with access to daylight as it makes them feel comfortable. These results should be taken on board by hospital designers and regulation makers as an indication of the importance of using good daylight in hospital wards to achieve two important goals of improving both hospital staff working conditions and the patient's healing environment.
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International Journal of Energy Engineering 2013, 3(6): 287-293
DOI: 10.5923/j.ijee.20130306.02
Survey of Hospitals Lighting: Daylight and Staff
Safaa Alzubaidi1,*, Susan Roaf1, P. F. G. Banfill1, Raidh Ali Talib2, Abdullah Al-Ansari2
1School of the Built Environment, Heriot-Watt University, Edinburgh, United Kingdom
2Urology department, Hamad General Hospital, Doha, Qatar
Abstract Hospital staff’s preferences for daylighting to notions of the effects of daylight on patient’s recovery times and
processes, their experiences of daylight when treating and diagnosing patients and patient comfort levels is studied. A
questionnaire survey was developed as a tool to review subjective judgments of the staff lighting needs and satisfaction.
Responses obtained from one hundred and thirty four staff showed that seventy nine percent of the participants identify
daylight in patient’s room as a factor helping them do their work more easily, and Seventy seven percent of the surveyed
nurses and doctors claimed that daylight is an important element in patient rooms to aid in reviewing patient recovery through
recognizing and interpreting changes in patient skin color. Seventy eight percent of hospital nurses and all the surveyed
doctors believe that daylight has many health benefits including fast recovery and reduced length of stay for patients.
Moreover, ninety two percent of the surveyed staff stated that patients preferred to stay in rooms with access to daylight as it
makes them feel comfortable. These results should be taken on board by hospital designers and regulation makers as an
indication of the importance of using good daylight in hospital wards to achieve two important goals of improving both
hospital staff working conditions and the patient’s healing environment.
Keywords Daylight, Survey, Hospital Lighting, Staff Preferences, Patient Comfort, Recovery Process
1. Introduction
Good daylighting design in hospitals does not just depend
solely on the aesthetics or engineering of a space, but it is
strongly influenced by the psychology of the viewer, the
behavioural opportunities available to them and the
interactions between these factors and the Architecture of the
space itself. Our knowledge with these interactions is still
limited and has been hampered over the last half century by
the growing dependence on engineered solutions over less
prescriptive and product oriented building designs.
Daylighting is commonly underderstood to enhance comfort
and well-being for building occupants[1]. Architects were
traditionally masters of daylighting design although in recent
decades the increasingly heavy hand of both regulation and
standardization of design has led to a significant reduction in
the quality of daylighting design in most types of buildings
[2]. People in different places and climates respond to the
light in very different ways and experience it in terms of
what is recognized and felt, not only as visible spectrum. The
desert dweller may shun large windows because of excess
light and thermal gain while the northern Tundra dweller
* Corresponding author: (Safaa Alzubaidi)
Published online at
Copyright © 2013 Scientific & Academic Publishing. All Rights Reserved
will have almost the opposite response as they seek out the
visual, thermal and health benefits of sunlight.
Sunlight and human health has shown strong relation in
terms of improving wellbeing or causing serious disease.
The role of sunlight to boost the body’s crucial vitamin D
supply was presented by many researchers such as Mead;
Altomonte and Osmancevic et al[1, 4, 5]. A recent study by
Lusk and Lash has described the light as an important
element in hospital to improve mood and reduce stress[3],
and it’s well-known that sunlight was used as treatment of
tuberculosis in the 19th century sanitaria where a TB bug is
killed after five hours in sunlight[4].
Beauchemin and Hays found that treating patients in
sunny hospital rooms can reduce their stays in hospital
compared to other patients in dull rooms[12]. Moreover,
Walch et al found that sunlight can work as analgesic therapy
for patients and therefore can reduce the use of painkilling
medication in hospitals[16]. The power of light in healing
psoriasis, herpes and skin disorders were described in a
recent study by Osmancevic et al as a reliable curing source
[5]. In addition, many studies found that a lack of exposure to
sunlight causes many illnesses and syndromes such as
vitamin D deficiency, cancer, bone diseases, stress,
depression, seasonal affective disorder (SAD) and disturbs
the circadian rhythms[1, 3, 4, 6].
A hospital’s physical environment is seen as a place
imbued with high levels of stress for both staff and their
288 Safaa Alzubaidi et al.: Survey of Hospitals Lighting: Daylight and Staff Preferences
vulnerable patients and their families due to its nature[7]. For
hospital staff stress can be exacerbated by long hours, the
human situations they deal with and the need to avoid
making mistakes because of their potential high impact
consequences. For patients, research has shown that
hospitals are stressful places for three types of reason:
1) Psychological: Patients perceive a hospital as a
potential last place they visit in their life (danger of death)
and it is also a place where they become socially isolated[8].
2) Fear of the pain inflicted by and the consequences of
procedures associated with their treatment exacerbated by
the visual reminders of being surrounded by the types of
machines that are with both.
3) The hospital environment itself is perceived as
abnormal, alien and possibly hostile environments, due to its
special activities, odors and noises, especially noises
resulting from the pain of other patients[9].
Researchers have investigated a range of factors that
reduce the stressfulness of the hospital environment and
increase the comfort experienced by both staff and patients,
with the aim to increasing their well-being, reducing medical
errors and improving patient’s recovery times. These studies
concluded that lighting regimes in hospitals play an
important role in improving hospital environment for staff
and patients[6, 12, 14].
This paper investigates the impact of daylight in the
hospital in making staff work easier, increasing patient
comfort and reducing the duration of patient stays in hospital.
The study presents the findings of a survey distributed to
hospital staff designed to explore their subjective judgments
on daylight and their experience with its impact on their
work and on the patients. The needs of the human body in
relation to lighting can be categorized into two groups:
biological and visual lighting needs. These two needs require
balance in any lighting design, as health and performance
problems can occur when there are inadequate light levels
for biological stimulation or higher light level for visual
1.1. Patient Recovery and Comfort
Recent research has led to an understanding of some
factors that influence the recovery of patient in a healing
environment such as hospitals[12, 35]. Daylight is seen as
one of these factors due to its visual and non-visual impacts
on the human body[13]. Studies that have surveyed the
impact of daylight on mood or specific task performance in
hospitals are very few which trigger the need for more
research in this field[21]. A survey conducted at a healthcare
facility in Turkey found that hospital staffs have access to
sunlight during the working day feel less stress and more
comfort[20]. Another study carried out at health care center
to explore the impact of natural light on hospital staff
comfort found that more than forty percent of the surveyed
staff perceive the natural light in their workplace as having
positive impact on their work[23]. However, in most
hospitals, nurses’ stations lack the necessary exposure to
natural light. Therefore there is a need for further studies to
understand the significance of sunlight to staff, and its
impact on their mood and performance. In addition, some
studies on the relation between sunlight and patient healing
time suggest that daylight is one of the factors that would
help in reducing the length of patient’s stay in hospitals[6,
12]. Not only the visual spectrum of sunlight affects the
mood and comfort but the non-visual effects of light can
have important impact as well and can contribute to reducing
depression among people as suggested by recent studies[28].
Three impacts of the light effect on the human body are often
1) Physiologically: daylight has the effect of stimulating
the human circadian system and human visual system[14].
When light enters the eye it stimulates a complex process of
endocrine and autonomic responses that occur inside the
human body. Psychologically it can make a patient feel more
comfortable and at ease and this improves mood and the
immune system in the body[3].
2) Psychological: a study demonstrated that daylight can
help reduce the use of pain killer drugs for patients in a
retrospective study on two types of patients. The first of
which stayed in the bright rooms and others in dimmed
rooms. It was noted that those who stayed in brighter rooms
perceived less pain and took fewer analgesics, indicating that
they were less stressed[16].
3) Sociability: Lighting affects the emotional and
behavioral responses of patients. This had been referenced in
some studies which demonstrate the significant impact of
daylight on the patient’s perceived sociability, emotion and
1.2. Staff Comfort
4) Health care facility is a people-centric industry. A
variety of professionals are involved in providing different
services that include healthcare, medicines, therapy, food,
hospitality and extensive use of materials and equipment.
Hospitals are often challenging workplaces and can place
staff under extremes of stress. Therefore, it is important to
give staff easily managed working environments in terms of
spatial planning and appropriate visual comfort[13]. The
need to minimize the risk of failure in executing necessary
tasks requires good visibility by providing sufficient light
quantity, with consideration of the nonvisual issues of
lighting quality to enable staff to operate optimally. Studies
have identified some of the negative factors that significantly
impact staff such as inappropriate lighting lux level, color,
direction and setting[14, 19, 21]. Other studies suggest a
range of positive impacts of lighting on patient and staff
well-being arises from many factors which include daylight
effects[15, 26, 27].
A key issue for medical staff is the need to identify the
changes in the patient’s skin color which occurs with
physiological changes inside the body. For instance, when a
patient’s skin becomes yellow it may be due to some liver
problems, blue skin color might result from breathing
International Journal of Energy Engineering 2013, 3(6): 287-293 289
problems or red because of skin problems.
On the other hand, color changes may result from an
improvement in a person’s health over time. Therefore it’s
important to recognize the patient skin color and to do that
we need a light type that helps staff easily see these changes
and distinguish between them[16]. Researchers have studied
the influence of light types on the object’s color appearance
and found that Color Rendering Index CRI is the reference
for lighting ability to give the objects its true color. The high
CRI means actual object color. Daylight is considered as
owning the highest Color Rendering Index CRI reaching one
hundred percent[33, 36]; therefore it’s very desirable to have
it in any applications that need true colors, such as in
hospitals where observing any changes in patient’s skin color
may be crucial[17].
1.3. Previous Questionnaires
Many survey questionnaires have been conducted to
explore the relationship between employee performance and
few of these surveys look at the relation between light and
patient comfort with daylighting[22, 23, 25]. In a survey
conducted at a newly constructed healthcare center in
Malaysia, the author of the study showed that staff age has a
strong impact on the selection of daylight preference when
treating patients[24].
Over sixty percent of participants (nurses) of forty years
old or under believed that serving medication orally for
patients in open wards with natural lighting is hassle-free,
while older nurses expressed their dissatisfaction in
performing the same task with natural lighting.
The number of years of experience was another subject
studied during one survey, where it was shown that over fifty
percent of the hospital professionals who have different
years (more than three years) of work experience performed
one task using artificial lighting without having difficulty.
Less than eighteen percent with less than three years’
experience stated that they found some difficulty in
performing the same task with natural light[24].
In a study conducted at an office building in South Korea
by Geun Young Yun[25], a field survey on illumination
levels and light type showed that employees felt more
comfortable with good daylight entering into the office,
especially when the brightness level was adequate. It
demonstrated that a linear relationship exists between the
comfort illuminance and the level of illuminance perceived
by occupants as being neither bright nor dim. Applebaum et
al conducted a survey to explore the relationships between
environmental factors like light and perceived stress for
The study showed a relationship between staff working in
acute-care settings and observed stress which was reduced
when working in an area lit with daylight. This could be the
result of the nature of the acute-care area and the type of light
it used to have (dimmed)[27].
2. Methodology
In the current study a structured interviews technique were
selected to collected data from a focus group, face to face
interviews were conducted to explore the staff satisfaction
with hospital lighting in which the questions were read as it’s
written on the questionnaire without explanation or
clarification. The survey was administered from January 2nd
till April 2nd 2013. The questionnaire was aimed at hospital
professionals who visit the patient on a daily basis. The
survey initially tested with fifteen volunteered participants
(pilot survey) to ensure clear and understandable content of
the questionnaire, in the next stage, one hundred and thirty
four participants volunteered to participate were asked
twenty eight questions, but for the purpose of this study we
will present their response on four questions that show their
preference and experience with daylighting at patient rooms.
The study was conducted at Hamad General Hospital
(HGH) the central healthcare facility in Doha, Qatar. The
hospital contains 603 beds that offer different health support
departments, such as emergency medicine, pediatrics,
specialized surgery, critical care, laboratory medicine,
specialized medicine, and radiology services[28]. It provides
health care services to more than 600,000 people.
The primary focus group consisted of doctors, nurses,
administrators and auxiliary staff, the subjective judgment
was assessed by the means of a questionnaire. The
qualitative professional judgments of staff used as the
reference indicator, surveyed in the study for a range of types
of work, as daily observations in different patients’ rooms.
2.1. Questionnaire
In order to explore the relationship between staff
preferences for hospital lighting and current lighting design
standard, twenty eight questions have been asked. In this
paper we consider the analysis of only four questions and
focus on the two groups, nurses and doctors. Following a
verbal introduction to the nature and purpose of the survey
and acquiring the background information about the
participant, the subjects were then asked to rate their
satisfaction with the following four questions:
1. Do you think it is easier to treat patients in a room with
Strongly agree Agree Neither
Disagree strongly disagree
2. If identifying changes in a patient skin colour is
important to you, do you find it easier to do it in a room with
Strongly agree Agree Neither
Disagree strongly disagree
290 Safaa Alzubaidi et al.: Survey of Hospitals Lighting: Daylight and Staff Preferences
3. In your view, do rooms with daylight help patients feel
more comfortable and at ease?
Strongly agree Agree Neither
Disagree strongly disagree
4. In your opinion, do wards with daylight help patients
recover faster?
Strongly agree Agree Neither
Disagree strongly disagree
2.2. Sample Size
An important question in any survey is how many
participants are needed to make the survey statistically
significant, an issue that needs to be determined before the
beginning of the survey to ensure useful results[29]. There
are many factors that influence this selection, such as the
main aims of the survey, the required precision level for
results and anticipated response rate. For the current survey a
large number of randomly surveyed staff were targeted who
were selected from a range of different professional groups
working in the hospital. Thus we were able to harvest
opinions from most of the working staff in the hospital. In
answer to the question of the optimal size for the group
surveyed, we referred to the work of Niles[30] who defined a
suitable confidence interval for the result with the following
the equation:
K= 1/√N (1)
K is the confidence interval
N is the number of participants or sample size.
In this study 134 subjects were selected to ensure an
acceptable margin of error[31, 32].
2.3. SPSS
For the purpose of this study IBM SPSS Statistics
software was used to analyze the staff responses to the
survey questionnaire. This software was developed by IBM
and is used mainly for handling data, running statistical
analyses, and producing tables or graphs to summarize the
data. Its features, including the ability to work on different
variables at the same time and the range of the tools included
in it. , it’s been considered satisfactory for use in this analysis
of the survey database and table production[32]. Especially
useful here were the functions it contains for recoding data,
tables, graphs and adding many new variables.
3. Results and Discussion
The participants were randomly selected from the
professional groups in the hospital including doctors, nurses,
auxiliary staff, administrators and technicians, who were
asked to participate voluntarily in this survey. Nurses
represented the highest percentage of those interviewed as
they represent the majority of staff in the hospital. The
proportion of staff from different groups in the survey is
shown in Table 1.
Figure 1 shows that seventy nine percent of the staff
believes that daylight in patient’s room helped them do their
work more easily, including treating and diagnosing patient
health and monitoring their recovery. This is an important
finding, especially because it springs from people who spend
most of their working day inside the hospital and are thus
well versed in the relative merits of daylight versus artificial
lighting. Nineteen percent of respondents expressed their
uncertainty in responding to this statement. Two percent of
the participants disagreed with this statement as they don’t
consider daylight an important factor that can make their
work easier.
Table 1. Participant Staff by groups
Administrators &technicians
Auxiliary staff 13%
Technician 14%
Figure 1. Treat Patient in room with Daylight
Responses from the professional groups on the first
question are presented in Table 2. It showed that eighty one
percent of the nurses who give treatment to patients support
the opinion of having daylight in the patient’s room and see
daylight as a factor which helps them do their work more
easily at the hospital. Most of them said “we feel more
comfortable when treating patients in rooms with daylight”.
All participants from the doctors group showed strong
agreement with this statement. Nineteen percent of the
nurses groups were unsure whether daylight can make their
work in the patient rooms easier. This could be due to other
factors which are not linked to the type of the profession,
such as age, work shift or years of experience as stipulated in
earlier study[24]. However, these factors were not
investigated in this study. On the other hand, participants
who chose neither as answer or disagreed with the statement
came from non-medical staff such as administrators and
technicians, who don’t spend much of their time in patient
rooms or their work is not linked to the patient treatment.
For the second question, the responses were analyzed and
the results on the hospital’s professional groups who believe
that daylight can help identifying changes in a patient skin
who choice this option
International Journal of Energy Engineering 2013, 3(6): 287-293 291
colour are shown in Figure 2. Staff were asked if they find it
easier to identify changes in a patient’s skin colour in a room
with daylight. The results confirmed that the perception of
seventy one percent of the staff think daylight plays an
important role in recognizing changes in patient skin color.
The daylight features of providing brighter light source
during the day and having a more balanced colored spectrum
than other light sources contribute to it being a suitable
source to be used in patient rooms. Two percent of the staff
disagreed with this statement as they don’t consider that
daylight has this capability, while twenty seven percent were
unsure of the ability of daylight helping them see changes in
patient’s skin color.
Table 2. Daylight Preferences when Treat Patient
Strongly agree
Auxiliary staff
Technician 6%
Technician 8%
Figure 2. Daylight helps identify patient skin colour
Table 3. Daylight helps identify patient skin colour (by profession)
Status Profession Percentage
Strongly agree Auxiliary staff
Doctor 7%
Agree Nurse 45%
Technician 6%
Disagree Administrator
Neither Administrator
Nurse 13%
Question two’s groups were represented in Table 3. The
interesting finding is that all doctors participating see
daylight as an important factor that can help facilitate their
work with the patient, including diagnosis of patient true skin
color. Seventy seven percent of the nurse group agrees with
this concept and twenty three percent of them are not certain
of this idea of daylight’s role in facilitating the diagnosis of
the patient’s changes in skin color. This response from
hospital’s staff highlights the need for a hospital architect to
take into consideration the effect of daylight on hospitals
The results of the question asking whether daylight makes
patient feel comfortable are shown in Figure 3. A very high
percentage (ninety two percent) of the staff agreed with this
statement highlighting the need for hospital designers to take
this fact on board. This finding also confirms the results of
earlier studies on the positive psychological effect of
daylight[12, 13, 22].
Figure 3. Daylight makes Patient Feel Comfortable
Staff groups who supported the idea of the positive
psychological effect of daylight in making patients feel more
comfortable were seven percent doctors, fifty six percent
nurses. This means almost all doctors and nurses observe the
effects of daylight on patients and how it makes them feel
comfortable. One percent of the surveyed nurses disagreed
with this option. This disagreement with nurses might be due
to other factors such as the type of patient illness they work
with (i.e. those in intensive care units who don’t have access
to daylight or who may have sensitivities to sunlight). The
results of the groupsreply are shown in Table 4.
Table 4. Daylight makes Patient Feel Comfortable
Status Profession Percentage
Strongly agree
Auxiliary staff 13%
Technician 8%
strongly disagree Nurse 1%
As discussed earlier, reducing the length of stay for
patients in hospital has large cost benefits for most involved
parties, including reduced health care costs for patients and
for hospitals[34]. It means a faster turnover rate for beds and
enhanced reputation for healing. Moreover, when the
healthcare facility is funded by the government (e.g.
non-profit facility), it means reduction in the running cost.
The subjective judgment of the surveyed staff shows that
eighty two percent of the hospital staff see daylight as an
element that can help speed up the recovery process for
patients and hence reduce the length of stay in the hospital.
However, eighteen percent of the staff were uncertain of the
health, comfort or diagnostic benefits of daylight. The
Strongly agree
6% 1%
Strongly agree
292 Safaa Alzubaidi et al.: Survey of Hospitals Lighting: Daylight and Staff Preferences
reasons for this were not identified in this study but point to
the need for further work in this field.
The agreement among the doctors group reveals that all
the surveyed doctors are in consent with this feature of
daylight (healing feature), seventy eight percent of the nurses
have concluded from their experience with patient and
healing process that daylighted rooms result in fast recovery
of the patients, twenty two percent of the nurses were unsure
of this statement applicability when linked to patient
recovery time; the same is illustrated in Table 5.
Figure 4. Daylight makes Patient Recover Faster
Table 5. Daylight makes patient recover faster
Strongly agree
Administrator 7%
Doctor 4%
Auxiliary staff
Nurse 44%
Technician 8%
4. Conclusions
This study has confirmed that hospital staff perceive
daylight to have a strong health, comfort and diagnostic
benefit for staff and patients in hospital wards. The study
provided clear evidence of the subjective judgment of
hospital staff showing:
Seventy nine percent of the participants identify
daylight in patient’s room as a factor helping them do their
work more easily.
Seventy seven percent of the surveyed nurses and
doctors claimed that daylight is important element in
patient rooms to aid in reviewing patient recovery through
recognizing and interpreting changes in patient skin color.
When it comes to patient comfort ninety two percent
of the surveyed staff stated that patients preferred to stay
in rooms with access to daylight as it makes them feel
Seventy eight percent of hospital nurses and all the
surveyed doctors believe that daylight has many health
benefits including fast recovery and reduced length of stay
for patients.
This study has presented the view of people who deal with
patients on a daily basis and do their work with different
lighting regimes (with and without daylight). The clear
evidence presented above of the perceptions of hospital
staffs of the health, comfort and diagnostic benefits of
daylight spaces should be taken on board by hospital
designers as an indication of the importance of using good
daylight in hospital wards to achieve two important goals of
improving both hospital staff working conditions and the
patient’s healing environment.
This study was carried out as part of a Ph.D. study at
Heriot Watt University UK. Many thanks to the management
of Hamad Medical Corporation and Hamad General Hospital
staff for their support and participation in the survey. Many
thanks to Mrs. Jackie Stalley for helping in editing this study.
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... Hospitals in general are stressful places for patients and visitors mainly due to fear of death, pain and noises. Therefore, providing better healing environment would help them relieve the stress and would also improve the outcome [18]. ...
... The recent studies have shown a strong relationship between daylight and human physical, psychological and mental health; it was found that daylighting has an impact on reducing depression [19], reducing the hospital length of stay [16,18], improving alertness and decreasing the consumption of killer pain drugs among hospitalized patients [5]. Whereas, the lack of exposure to natural daylight has a bad influence on the human health and may cause seasonal affective disorder [20], stress [21], delirium [22] and Vitamin D deficiency which is linked to many serious complications such as bone diseases, cancer, cardiovascular diseases, diabetes [23], autism, multiple sclerosis and schizophrenia [24]. ...
... Access to daylight can significantly improve nurses' satisfaction and has a good impact on reducing job burnout [37]. A survey study was conducted in Hamad General Hospital in Doha, Qatar, emphasizes this positive effect of daylight on staff satisfaction, where 79% of the medical staff ensure their belief in the importance of daylight in patient's room to help them doing their job easily, including treating, diagnosing (i.e.: noticing the changing in patient's skin color) and monitoring patients [18]. The architectural design of healthcare rooms and ICU should be an evidence-based design that consider all functional and physical aspects to meet patients, staff, and visitors physical, psychological and mental requirements. ...
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The quality of the healthcare in intensive care unit (ICU) is directly influenced by its design. Daylight and access to the outside views are key factors to improve the healing environment for patients and working conditions for healthcare providers. In addition, augmenting the use of natural light not only helps with sustainable solutions, but also reduces energy costs. Beside the geographic location, natural lighting in any space is affected mainly by five parameters: window orientation, window level, window to wall ratio, walls light reflectance and the used shading device. This study aims to optimize these parameters using DesignBuilder software to achieve the optimal daylighting while minimizing the heating and cooling loads without restricting patients’ access to view. The results show that the South was the optimum orientation. 2.5 m was the optimum window lintel level height. Furthermore, the shading device’s type and depth differed according to window orientation.
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Today's customers tend to select eating-places for satisfying pleasures through experiential socialization. This study explores how color, lighting and dŽcors have effects on customers’ perceived sociability, emotion and behavioural intention on social dining occasions. Experimental method was used and 162 senior students were involved. The results showed that the restaurant with monochromatic colors, dim lighting and plain dŽcors yielded a statistically significant difference in the entire dependent variables with almost any other interior conditions on romantic dining, as opposed to the case of casual dining. Further research on subtler and diverse dimensions of interior element is suggested to enrich previous findings.
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Based on a pilot study, this paper investigated how the quality services provided by the nurses could be achieved through proper lighting design in a recently built healthcare centre in Putrajaya, Malaysia. Data collection involved personal site observations, photographic documentations, interviews and questionnaire surveys. Overall, 120 nurses participated as questionnaire respondents. The SPSS analysis revealed that nurses’ age effects on their opinion about current lighting design of the hospital. Implication of this study is upon the proper lighting design which could enhance nursing care and minimize human errors, thus contributing towards a better quality of life within the healing environment.
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Lighting plays an important role in the Hospital Diagnostic and Treatment Room. It shall be environmentally and functionally suitable for three groups of people: patients, hospital professionals and visitors. On the other hand lighting is considered a major consumer of electrical energy and therefore, hospital lighting design should consider the visual performance, visual comfort and energy efficiency. This article discusses the performance of different types of lighting installations used for hospital lighting system design applications: first the visual comfort and second to save energy consumptions in such applications. DIALux 4.8 simulation software is used to study and evaluate the efficient lighting scheme for the hospitals through the use of different types of lamps. Also, visual environment lighting system design procedure is explained. Economics of different lighting scenarios are highlighted
In this research, a field investigation was done with 263 coronary artery bypass graft (CABG) surgery patients to identify the impact of daylight exposure on patient length of stay (LoS) in hospital. Lighting data were collected by installing sensors inside in-patient rooms, and were used to develop a multiple linear regression (MLR) model to explore the relationship between daylight intensity and patient LoS in the presence of other environmental (i.e. provision of outdoor view and room status) and clinical (i.e. mean arterial pressure, heart rate and diabetes mellitus) variables. The coefficient estimates of the developed MLR model suggest that while holding the other explanatory variables constant, the patient LoS reduced by 7.3 hours per 100 lx increase of daylight inside in-patient rooms.
This study investigates how indoor environments with lighting during the day affect patients’ average length of stay (ALOS) in a hospital, by measuring and evaluating the daylight environments in patient rooms and comparing results to their ALOS. Patients’ ALOS data were compiled at a general hospital in Incheon, Korea, and the physical, environmental, and daylight conditions in the building were assessed. Data gathered were analyzed using a statistical package to determine the trends in the patients’ length of stay in hospital wards using 95% and 90% statistical significance levels. The data were categorized based on the orientation of each patient’s room and the positions of the heads of their beds in relation to window views. Comparisons were made between the different orientations of patient rooms in each ward of the selected hospital.The variables considered in this study were: each patient’s average length of stay as an index of health outcome, and the differences in environments during daylight hours, including illuminance, luminance ratio, and diversity of illuminance in the patient rooms of the hospitals. This study considered how these components affected patients’ ALOS in the hospitals. It discusses the relationship between indoor daylight environments and ALOS, as well as the seasonal weather factor effect on indoor daylight that could potentially influence the patients’ length of stay.This study can serve as a basis for the development of recommendations for designing patient rooms in healthcare facilities that will result in more effective healing environments.
Several aspects of the Color Rendering Index (CRI) are flawed, limiting its usefulness in assessing the color rendering capabilities of LEDs for general illumination. At NIST, we are developing recommendations to modify the CRI that would overcome these problems. The current CRI is based on only eight reflective samples, all of which are low to medium chromatic saturation. These colors do not adequately span the range of normal object colors. Some lights that are able to accurately render colors of low saturation perform poorly with highly saturated colors. This is particularly prominent with light sources with peaked spectral distributions as realized by solid-state lighting. We have assembled 15 Munsell samples that overcome these problems and have performed analysis to show the improvement. Additionally, the CRI penalizes lamps for showing increases in object chromatic saturation compared to reference lights, which is actually desirable for most applications. We suggest a new computation scheme for determining the color rendering score that differentiates between hue and saturation shifts and takes their directions into account. The uniform color space used in the CRI is outdated and a replacement will be recommended. The CRI matches the CCT of the reference to that of the test light. This can be problematic when lights are substantially bluish or reddish. Lights of extreme CCTs are frequently poor color renderers, though they can score very high on the current CRI. An improved chromatic adaptation correction calculation would eliminate the need to match CCT and an updated correction is being considered.
Occupants of buildings consciously interact with environmental systems to satisfy their specific needs for comfort. Field investigations have indicated that this adaptive behaviour of the occupants is a key factor in affecting the energy consumption of buildings and can change the energy use of similar buildings by a factor of 2. This study aims to reveal the factors in determining lighting energy consumption of open plan offices with the emphasis on the roles of occupant adaptive actions. Field investigations of open plan offices in Seoul, Korea were conducted from 20 July to 29 September. Internal and external illuminance and the use of lighting were monitored at ten minute intervals. Seventy seven office workers filled in the questionnaire survey forms five times a day for 40 days. Results reveal that there were close relationships between prevailing illuminance levels on the work plane and luminous comfort. This study presents the hourly profiles of both lighting use patterns and lighting energy consumption, and investigates the lighting energy consumption of open plan offices in relation to internal illuminance, visual comfort and lighting system use patterns.
It is generally taken for granted that people like sunshine inside buildings, provided thermal and visual discomfort are avoided. Obviously the degree to which sunshine is liked is dependent on climate, tradition and sometimes on prejudice. It is a common practice in building design to deal with the thermal aspects of sunshine and their control, while visual aspects of sunlight are not adequately considered. Recent studies have indicated that as a result of the trend towards improved thermal comfort in buildings, the visual aspects of sunlight have assumed a higher degree of importance for the well being of occupants. Further studies have been made of the effect of the presence of sunlight and also of the degree of exposure of occupants to the Sun.