Facu

lty

of A

rch

itec

ture

Prof. dr. ir. Philomena M. Bluyssen MBA

Understanding the indoor environment

Inaugural speech May 22, 2013

2

2 1

Understanding the indoor environment

Inaugural speech

Spoken on May 22, 2013at the occasion of her acceptance of the position of full professor of Indoor EnvironmentAt the Faculty of Architecture of the Delft University of Technology

by

Prof. dr. ir. Philomena M. Bluyssen MBA

2

2 3

Mijnheer de Rector Magnificus,Leden van het College van Bestuur,Collegae Hoogleraren en andere leden van de universitaire gemeenschap,Zeer gewaardeerde toehoorders,Dames en heren, jongens en meisjes, vrienden.

Sir rector,Members of the Executive Board,Fellow Professors and other members of the university community,Honourable listeners,Ladies and gentlemen, boys and girls, friends.

1. IntroductionWhile most people are aware of the importance of the outdoor environment, especially in relation to climate change issues but also related more directly to our health, the effects of indoor environment quality are not that common knowledge. Who doesn’t know by now that air pollution such as fine dust and noise pollution from aeroplanes are important issues, or that too much sunlight can be very unhealthy. Most of us don’t realize that people in the Western world in general spend 80-90% of their time indoors (e.g. at home, at school and at the office). Exposure indoors is thus much longer than outdoors. Nevertheless, the understanding of that indoor environment has only just began.

How to achieve a healthy indoor environment has been an issue among architects, engineers and scientists for centuries. However, it was not until the early decades of the twentieth century that the first relations between parameters describing heat, lighting and sound in buildings and human needs were established. For most of the time, science has relied on the optimisation of single factors such as thermal comfort or air quality. The realisation that the indoor environment is more than the sum of its parts, and that its assessment has to start from human beings rather than benchmarks, has only been gaining ground in recent years.

Figure 1 Starting from

human beings rather

than benchmarks

(Bluyssen, 2013:

Figure 1.2 S.Meertins).

4

2. Indoor environment

2.1 Indoor environment qualityThe indoor environment can be described by environmental factors or (external) stressors such as (Figure 2):- Indoor air quality: odour, indoor air pollution, fresh air supply, etc.- Thermal comfort: moisture, air velocity, temperature, etc.- Acoustical quality: noise from outside, indoors, vibrations, etc.- Visual or lighting quality: view, illuminance, luminance ratios, reflection, etc.

These various factors have slowly become incorporated within the building process through environmental design. However, aesthetic quality and spatial and ergonomical quality are also part of the indoor environment. In fact, historically these parameters received the most attention when designing a building. The chair “Indoor environment” merely focuses on the environmental parameters, without downgrading the dimensions and aesthetics of shapes and spaces. As Hawkes (2008) writes: “The interaction of light and air and sound with the form and materiality of architectural space is of the very essence of the architectural imagination.” And note the way in which Pallasmaa (2005) describes the essence of Architecture comes even closer to what I want to tell you “Architecture is the art of reconciliation between ourselves and the world, and this mediation takes place through the senses.”

Figure 2 What is indoor environment quality? (Bluyssen, 2009: figure 3.1)

Although chemistry was only seen as a separate science during the 17th century, from the Middle Ages until the beginning of the 19th century people began to

Acoustical quality

Thermal comfort

Lighting quality

Air quality

4 5

realize that air in a building should be good and if not, could result in diseases or at least extreme discomfort (bad smells). The miasmatic theory of disease, now taken over by the germ theory of disease (micro organisms are the cause of many diseases), was used to explain the spread of disease such as cholera. Miasma (Greek for pollution) was considered to be a poisonous smelly vapour or mist that is filled with particles from decomposed matter (miasmata), which can cause illnesses. Ventilation thus became an important part of the indoor environment. Discussions on how much ventilation is sufficient to prevent the spread of disease and to provide adequate comfort (no noxious odours) were born and are still taking place.

Indoor air quality is determined by the pollution or pollutants occupants are exposed to over time. The pollutants originate from outdoor air (the air coming into the building), are caused by the building itself and the heating and ventilation systems (when they are present) and pollutants are emitted by the occupants and by activities they perform such as smoking, candle lighting but also cooking, showering, cleaning and printing. These different sources of pollution can create/produce different types of pollutants. Some gaseous pollutants smell, others do not, such as for example Carbon monoxide. And then there are several other pollutants in that indoor air, which influence the air quality such as water and particles (biological - house dust mite and legionella but also from materials such as asbestos fibres). While in the 90ties it was acknowledged for the first time that people are not the only contributor to indoor air pollution (Bluyssen et al. 1996) and thereby opening the discussion of applying CO2 concentrations only as the indicators for indoor air quality, several national and international projects have been undertaken. Two of the latest European projects are OFFICAIR and SINPHONIE, focussed on the effects of indoor air quality in office buildings and schools on office workers and children, respectively (www.sinphonie.eu and www.officair-project.eu). These health effects range from annoyance to irritating effects and allergic response, to serious health threatening effects.

Another aspect of indoor environment quality is thermal comfort, the parameter we are the most familiar with, including aspects such as feeling warm, cold, draught etc… During the late 19th century, ‘thermal comfort’ was introduced as an environmental factor that is part of overall indoor comfort. In addition to poor air quality, poorly ventilated rooms can also result in unwanted thermal effects (both through temperature and humidity). The thermo-physiological model, developed in the 1970s by Prof. Fanger in Denmark, who tested his model in climate chambers using several subjects, is still the basis for guidelines on thermal comfort. Nevertheless, another model, based on field studies of people

6

in daily life, slowly begins to win ground (de Dear and Brager, 2002): people undertake action to improve their thermal comfort when they are uncomfortable and therefore indoor comfort temperature ranges might be different for different outdoor temperatures but also for different forms of control present (such as opening windows, adjusting thermostates etc.). In other words the context and preferences of the occupant are important to consider. And then even more recently it was suggested that thermal neutral conditions do not have to be necessarily healthy (Marken Lichtenbelt et al. 2009).

The positive health effects of (sun) light were already acknowledged by the Egyptians, Romans and the ancient Greeks, who worshipped the sun gods. Much later, at the beginning of the 1900s, sanatoria were built for light therapy for people suffering from, among other ailments, skin diseases. During the late 1980s, light therapy, with artificial light, began to be used to cure winter depressions. Artificial lighting has been an applied science since around the 1890s, when the development of the first electrical lamps made the extension of the working day into the dark hours possible.

Light plays a major role in Architecture. Vision is the primary sense through which we experience architecture and light is the medium that reveals space, form, texture and colour to the eyes. The parameter visual or lighting quality comprises of aspects such as illuminance, luminance ratios and colours and aspects you would rather prevent such as reflection on a floor or other surface. But visual comfort is more than providing enough light to perform a task, view is also an important aspect to consider. Another important issue with lighting quality, is the use of natural versus artificial lighting, especially in relation to energy use.

Lighting conditions that cause visual discomfort can lead to eyestrain and headaches. While current guidelines are focused on providing sufficient task lighting, research on biological lighting demands has revealed that the dosing of natural light is important for health purposes. The amount of light that enters the eye affects our bio-rhythm: Under influence of light, the hypothalamus signals to the pineal body to produce melatonin, a hormone that makes us want to sleep (Figure 3). If exposed to light during night, the production of the anti-oxidant melatonin is immediately stopped, alertness and core body temperature is increased and sleep is distorted (Hinson, Raven and Chew, 2010). With regard to sound, the ancient Greeks and Romans realized that good auditory conditions for an audience listening to speech or music, whether indoors or outdoors, are important. They placed audiences on steep hillsides to

6 7

reduce distance and to concentrate sound. However, not all noise was welcome though: like bad air, it can be something that we would rather do without. Noise or unwanted auditory experience became an important aspect of practical acoustics in the 1970s. It was considered a form of environmental pollution and noise control developed into a major branch of acoustical engineering. Acoustical quality is influenced by noise from outside, indoors, vibrations, etc. Noise protection, noise insulation from noise outdoors but also indoors are very important issues, especially because we know how important a good night sleep is for our health. Noise has been associated with direct and indirect stress reactions. Annoyance is an important aspect in this mechanism (see Figure 4).

It seems that noise effects do not only occur at high sound levels, but also at relatively low environmental sound levels, when certain activities such as concentration, relaxation or sleep are disturbed. In office buildings major indoor sources of noise are HVAC (Heating, Ventilating and Air conditioning) systems and people (colleagues). Control over noise in an office environment has been significantly (negatively) related with discomfort (Bluyssen et al., 2011). In homes, major sources are noise from neighbours and noise from outside such as noise from traffic.

Visual 

cortex 

Re/na 

Pineal body 

Hypothalamus 

Figure 3

Pathway of light signal to pineal

body: The signal from the retina as

a result of light, is relayed through

the hypothalamus down the spinal

column, returning via the superior

cervical ganglion to supply the pineal

gland (Bluyssen, 2013: figure 3.5).

Noise exposure (sound level) 

  High        Moderate 

Direct pathway  Indirect pathway 

Hearing loss  Disturbance of 

ac;vi;es, sleep, 

communica;on 

Cogni;ve and 

emo;onal response Annoyance 

HPA‐axis 

Figure 4

Noise effects reaction schema

(Bluyssen, 2013: figure 3.3).

8

2.2 Indoor environment and controlOver the years, control of indoor environmental factors has merely focused on the prevention or curing of different related observed physical effects in a mostly isolated way: thus trying to find solutions for thermal comfort, lighting quality, sound quality and air quality separately. Table 1 shows an overview of the indoor environmental parameters per indoor environmental factor with which some form of control can be performed. Additionally, the control measures are presented.

Table 1 Indoor environmental factors, parameters and control (Bluyssen, 2009).

The best way to control exposure to pollutants (air quality) is to perform source control (i.e. to minimize the emission of either primary or secondary pollutants to the air which we are exposed to). Besides source control there are three other ways to control the exposure, directly or indirectly: ventilation, air cleaning and activity control (e.g. designating smoking areas in a non-smoking building).

Thermal comfort can be controlled by the design of the building (e.g. insulation, type of materials, etc.). However, in general so-called heating, cooling and air-conditioning systems are applied in divers combinations. Heating can be provided through convection, conduction, radiation and air systems. Regulation of relative humidity can be provided through (de)humidification systems via an air conditioning system or locally. In addition, one can adjust one’s clothing and type of activities.

Thermal comfort

Lighting quality Acoustical quality

Air quality

Parameters Temperature (air and radiant)Relative HumidityAir velocityTurbulence intensityActivity and clothing

Luminance and illuminanceReflectance(s)Colour temperature and colour indexView and daylightFrequencies

Sound level(s)FrequenciesDurationAbsorption characteristicsSound insulationReverberation time

Pollution sources and air concentrationsTypes of pollutants (allergic, irritational, carcinogenic, etc.)Ventilation rate and efficiency

Control Heating, cooling and air-conditioning systemsDesign of building (e.g. insulation, façade)

Luminance distributionIntegration artificial and natural lightingDaylight entrance

Acoustical controlPassive noise controlActive noise control

Source controlVentilation systemsMaintenanceAir cleaningActivity control

8 9

Comfortable light doesn’t cause blinding (through lighting systems or direct sun light), or flickering or stroboscopic effects and glare (e.g. from computer screen), and produces good colour impressions, with no reflection and an equal distribution of light. Positioning and intensity of lighting systems, surface area treatment (e.g. mat surface area and colours), solar screens and solar reflecting glazing are means to achieve this. Comfortable light also signifies controllability and healthy light (day-night rhythm). The latter can be provided by offering the right variation on light intensity and colour temperature on the right time. With automatic or manual dimming or intensifying of light, an appropriate integration of artificial light and daylight can be achieved.

Control strategies can be performed to prevent noise from entering a space or approaching a person, or to make the space perform better acoustically. With respect to the latter besides the reverberation time and the speech-background noise ratio, speech audibility is influenced by the speaker, the communication channel and the listener. Speech intelligibility can therefore be augmented by improving the speech-background noise ratio, by shortening the reverberation time, and by improving the clarity and loudness of speech. By introducing absorbing material and/or decreasing the volume, the reverberation time can me shortened. Introduction of absorption material also decreases the sound pressure level and suppresses echoing. Prevention or reduction of noise entering a space can be established by preventing/closing of sound leaks, prevention or reduction of contact sound transmission, and/or applying active (noise) control.

3. Indoor environment and healthThere are many indoor stressors (e.g. thermal factors, lighting aspects, moisture, mould, noise and vibration, radiation, smell, chemical compounds, particulates) that can cause their effects additively or through complex interactions (synergistic or antagonistic). It has been shown that exposure to these stressors can cause both short-term and long-term effects (Bluyssen, 2013).

Indoor air pollutants can:- Be odorous and lead to annoyance or pleasure.- Stimulate the trigeminal nerve endings in nose and eyes, causing irritation.- Disrupt endocrine function.- Cause oxidative stress, inflammatory and allergic responses.- Induce cell alterations and even cell death.

10

Thermal stress occurs when one is not able to regulate its thermal balance or when one believes or perceives it isn’t possible. The psychological effect of expectations and the perceived individual level of control seems important. However, recent studies indicate that increased exposure to thermal neutral conditions might be related to increased adiposity. Additionally, it has been shown that the thermal environment can affect sleep, specifically the REM (Rapid eye movement) sleep.

Radiation (light) wrongly used or exposed can be looked upon from several angles:- Visual discomfort, which can lead to eyestrain.- Improper lighting, that can cause disturbance of the circadian rhythm.- Damage of eye and skin through both photochemical and thermal mechanisms.- Different colours can directly affect an individual’s impression of the

environmental parameters thermal comfort, sound and light.

Noise is typically defined as an unwanted sound or combinations of sounds that may adversely affect people. The mechanisms of physiological damage from noise is not completely understood, but several mechanisms have been demonstrated:- Traffic noise exposure has been associated with changes in stress

hormone levels, with cardio-vascular changes, and has been related to the parasympathetic and sympathetic balance.

- Road traffic noise has been identified as a major cause of sleep disturbance.- Oxidative stress in chronic noise exposure leading to noise induced hearing loss.- Acoustic trauma causing mechanical disruption of the cochlea, which may

result in permanent hearing loss.

Previous studies have shown that the relationships between indoor building conditions and wellbeing (health and comfort) of occupants are complex. In office buildings, a whole range of effects have been associated with these stressors such as Sick Building Syndrome (SBS), building related illnesses and productivity loss. People in the Western world in general spend 80-90% of their time indoors. And the increased asthma prevalence in most countries in the past decades, it has become the first chronic disease in childhood, seems to put a finger to the indoor environment of schools and homes. More recent studies have indicated that indoor building conditions may be associated with mental health effects (Houtman et al., 2008), illnesses that take longer to manifest (e.g. cardiovascular disease and lung cancer) (Lewtas, 2007), a variety of asthma-related health outcomes (Fisk et al. 2007) or obesity (Bonnefoy et al. 2004).

10 11

4. GapsWhy do we have still do not have this under control? Even after more than 100 years of R&D. To my opinion there are at least two major gaps contributing to an explanation for this situation.

4.1 Standards and end-users wishes and needsOn the one hand: A gap or lack of knowledge shown by the discrepancy between standard and end-users wishes and needs! Even though standards are met, complaints and symptoms occur. Why and how do people respond, and which indicators can be used is thus an important question to answer.

Human exposure to environmental factors (such as indoor air compounds) occurs mainly through the senses. Receptors in our nervous system receive sensory information as sensations via the eyes, ears, nose and skin, enhanced by bodily processes such as inhalation, ingestion and skin contacts. Most of us are familiar with several reactions of the human body to certain stimuli such as sweating when warm, closing/narrowing your eyes with a sharp light, covering your ears with loud noise and temporarily stop breathing with a bad smell, allergic reactions to pollen or even certain inflammation and infection defence mechanisms of the immune system upon an injury of the epithelium (the “skin” of an organ).

In addition to the stimuli that can be processed by our sensory system, the environment affects us in other ways, which are not always recognisable to us and which we are not (immediate) conscious of. The latter stimuli can cause changes in our physiological and psychological state. These changes can be harmful to our physical state of wellbeing on the long term even though the exposed levels are well below current set threshold levels. External stress factors seem to be able to result in both mental and physical effects.

As was shown many control strategies for these parameters have been implemented in order to minimise or prevent possible diseases and disorders of the human body and its components. Only in the last decades of the 20th century an attempt was made through epidemiological studies to approach the indoor environment in a holistic way. The scientific approach towards evaluating and creating a healthy and comfortable indoor environment developed from a component-related to a bottom-up holistic approach that tried simply to add the different components. Performance concepts and indicators emerged, including not only environmental parameters but also possible associated variables such as characteristics of buildings. New methods of investigating IEQ from different perspectives were introduced. Nevertheless, control strategies were still focused

12

on a component basis. Even though these control strategies are currently being applied, complaints and symptoms related to the indoor environment still occur.

The health and comfort indicators we are today familiar with can be divided in three groups of indicators:- The occupant or end-user: such as sick leave, productivity, number of

symptoms or complaints, health adjusted life indicators or specific building related illnesses.

- The dose or environmental parameter: concentrations of certain pollutants, indicators such as ventilation rate or CO2 concentration, temperature and lighting intensity.

- The building and its components: certain characteristics of a building and its components, such as possibility for mould growth or even labelling of buildings or its components.

Of these groups of indicators, the second one (dose or environment parameter related indicators) is used most frequently in guidelines and standards as well as in the commercial building assessment tools used at national level and in some cases more and more on international level, such as BREEAM (BRE Environmental Assessment Method) in the UK (www.breeam.org), LEED (Leadership in Energy and Environmental Design) in the USA (www.usgbc.org), CASBEE (Comprehensive Assessment System for Built Environment Efficiency) in Japan (www.ibec.or.jp) and Green Globes in Canada (www.greenglobes.com).

But the dose-response mechanisms are not straightforward. Ventilation rate is a good example of this. For most of the 20th century, appropriate ventilation was considered to be the only means to create acceptable indoor air quality. Recommendations for good indoor air quality were therefore always related to ventilation rate. Based on either CO2 as an indicator for bioeffluents or on certain emissions of building materials, minimum ventilation rates have been discussed and are still being discussed for almost two hundred years now (Figure 5).

Figure 5 The recommended

minimum ventilation rate

over the years (Bluyssen,

2009: figure 5.2).

9

Even though these control strategies are currently being applied, complaints and symptoms related to the indoor environment still occur. The health and comfort indicators we are today familiar with can be divided in three groups of indicators: - The occupant or end-user: such as sick leave, productivity, number of symptoms or complaints,

health adjusted life indicators or specific building related illnesses. - The dose or environmental parameter: concentrations of certain pollutants, indicators such as

ventilation rate or CO2 concentration, temperature and lighting intensity. - The building and its components: certain characteristics of a building and its components, such as

possibility for mould growth or even labelling of buildings or its components. Of these groups of indicators, the second one (dose or environment parameter related indicators) is used most frequently in guidelines and standards as well as in the commercial building assessment tools used at national level and in some cases more and more on international level, such as BREEAM (BRE Environmental Assessment Method) in the UK (www.breeam.org), LEED (Leadership in Energy and Environmental Design) in the USA (www.usgbc.org), CASBEE (Comprehensive Assessment System for Built Environment Efficiency) in Japan (www.ibec.or.jp) and Green Globes in Canada (www.greenglobes.com). But the dose-response mechanisms are not straightforward. Ventilation rate is a good example of this. For most of the 20th century, appropriate ventilation was considered to be the only means to create acceptable indoor air quality. Recommendations for good indoor air quality were therefore always related to ventilation rate. Based on either CO2 as an indicator for bioeffluents or on certain emissions of building materials, minimum ventilation rates have been discussed and are still being discussed for almost two hundred years now (Figure 5).

Figure 5 The recommended minimum ventilation rate over the years (Bluyssen, 2009: figure 5.2).

Diving into the literature of several fields of research it is clear that the relations between the stressors, the mechanisms that take place in the human body causing the diseases and disorders, are very complex. Response mechanisms of the human systems are being studied extensively. Roughly those mechanisms can be divided into two categories: mechanisms originating with the endocrine system (anti-stress mechanism, disturbance of sleep-awake rhythm and endocrine disruption) and mechanisms originating with the immune system (oxidative stress, inflammation and cell death and changes), afterwards affecting other bodily systems. For all of the bodily processes to function properly, integration and regulation is required, which is established through information transfer of our endocrine system (hormones), electrical signalling in our nervous system and transport processes between and in cells or over larger distances via blood and urine. Via hormones, the processes to regulate for example the sleep-awake rhythm and reproduction are controlled. The nervous system assures that the body activities and reaction to stimuli are regulated properly via perception and behavioural processes. To protect the human body from the external

0

2,5

5

7,5

10

12,5

15

17,5

20

1825 1850 1875 1900 1925 1950 1975 2000 2025

vent

ilatio

n ra

te (l

/s p

er p

erso

n)

year

12 13

Diving into the literature of several fields of research it is clear that the relations between the stressors, the mechanisms that take place in the human body causing the diseases and disorders, are very complex. Response mechanisms of the human systems are being studied extensively. Roughly those mechanisms can be divided into two categories: mechanisms originating with the endocrine system (anti-stress mechanism, disturbance of sleep-awake rhythm and endocrine disruption) and mechanisms originating with the immune system (oxidative stress, inflammation and cell death and changes), afterwards affecting other bodily systems.

For all of the bodily processes to function properly, integration and regulation is required, which is established through information transfer of our endocrine system (hormones), electrical signalling in our nervous system and transport processes between and in cells or over larger distances via blood and urine. Via hormones, the processes to regulate for example the sleep-awake rhythm and reproduction are controlled. The nervous system assures that the body activities and reaction to stimuli are regulated properly via perception and behavioural processes. To protect the human body from the external environment, we are equipped with layered protection mechanisms. The central nervous system (CNS) is responsible for the integration of it all.

While psycho-social stressors are mainly involved in the anti-stress mechanism and to some extent in the disruption of sleep-awake rhythm, the physical stressors have in general more relations. It seems that those stress mechanisms are triggered by more than one parameter or even factor (Figure 6).

Figure 6 Possible associations between stressors, mechanisms

and diseases & disorders (Bluyssen, 2013: figure 1.3).

Stressors Stress mechanisms Diseases &

Disorders

Anti-stress Depression

Noise Circadian rhythm Obesity

Indoor air quality

Endocrine disruption Diabetes

Lighting quality

Oxidative stress Chronic respiratory

diseases

Thermal comfort

Inflammation, irritation

Cardiovascular diseases

Cell changes/death Cancers

14

Besides the mechanisms and interactions at human level, interactions at parameter, building and environmental level are far from clear as well. These interactions as well as the risk factors responsible for a certain health effect are important to consider in order to get the complete picture. Basically, the following interactions determine how well you feel, how healthy you are and how comfortable you are at a certain moment in time, and determine your interaction with your environment over time (Figure 7):- Interactions at human level: Receiving information (sensations) can

be looked upon from the physiology of the human body and/or from the psychological point of view. Interactions occur on both levels. Interactions between people should not be forgotten; those interactions can also have a significant effect on the physical and psychological state of a human being in the indoor environment.

- Interactions at indoor environmental parameter level: Important interactions are for example chemical reactions between pollutants in the air and microbiological growth at indoor surfaces. Important interactions with the outdoor environment are for example noise from outdoors, fine dust and biological lighting.

- Interactions at building level: Interactions between elements of the building and between the building and the environment, such as interaction of the building with the ground it is build on (the foundation), interaction of outdoor environment with building (protection and transmission characteristics of the facade) and interaction of building with indoor environment (such as maintenance and emission of the indoor surfaces and the lighting, heating, cooling and ventilation systems that are integrated in the façade or not).

Figure 7 Interactions at different levels (Bluyssen, 2009: figure 9.1).

Human being Parameters indoors

Building and elements

External environment

Physical and

physiology

Indoor chemistry

microbiolo-

gical growth

Integrated

systems

Ageing population

Multifunctio-

nal society

Mental and

psychological

(fine) dust

Smart

Control

Climate

change and

related issues

Conscious

and

unconscious

Noise and

vibrations

Flexible

bearing

construction

Metaphysics

Health and

Comfort

Healthy

lighting

Indoor

surfaces

Risk

assessment

14 15

4.2 Building processOn the other hand: A discrepancy is seen between what end-users want/need and what they get, points not only to a lack of knowledge but also to an inefficient or wrong use of existing knowledge. The question’ How can existing knowledge be applied efficiently during the whole life cycle of a building?’ seems therefore just as important to get more insight in this complexity. Besides the discrepancy between standards and end-users wishes and needs, there also seems to be a discrepancy between what end-users want and what they get. This is often blamed to be related to the complex communication (Figure 8) and the fragmented structure of the building sector (Figure 9), leading to lack of coherency, lack of life cycle orientation and slow take-up of innovation.

Figure 8

Miscom-

munication in

the building

process?

(Bluyssen,

2009:

figure 8.1).

Figure 9

Traditional

building sector

stakeholders

and relations

(Bluysen,

2009:

figure 8.4).

 

As the contractor has made it

Space

Investment Maintenance

Occupation Regulation

Construction

As the regulator has visualised it

As the investor visualised it

How the occupant would like to have it

How the “Maintainer” would like to have it

Raw material industry

Processing industry

Building components industry

Trade

Building contractors

Owner/client

End-user

Architect

Sub-contractors

Advisors (systems,

structure, etc..)

National Authorities

Local Authorities

Project independent

Project dependent

16

Answers should be found in the way communication takes place in the building process, lead by the different stakes of the stakeholders involved. The dynamic process of designing, constructing and managing the indoor environment, involves many stakeholders, such as the investor, owner, the end-user, the contractor, sub-contractors, local authorities and pressure groups, but also the persons that maintain the indoor environment. If those stakeholders do not understand each other, problems can occur. But answers can also be found in the fragmented structure of the buildings sector, leading to lack of coherency and slow take-up of innovation. In other words, the general awareness of what indoor environmental quality is, how you can improve it and who should or can undertake actions, is poor. That this is a fact was confirmed in the European project named Healthy Air. In HealthyAir, 105 parties comprising of producers of construction products, architects and designers and housing corporations in six countries and in EU were interviewed. They were asked among others about their knowledge on indoor air quality and what they do to realise good indoor air quality. Most of the interviewees did not consider IAQ to be a priority, and did not know how to improve it or who should undertake this. They didn’t see it as their responsibility. From the research performed was shown that this was related to the fact that they were not aware of the importance. It was concluded that most of the interviewed persons did not even know the meaning of air quality i.e. what specific aspects one would share under the general term ‘air quality (Bluyssen et al. 2010).

4.3 DriversIn addition to the gaps presented we can also see that the drivers for health and comfort in the indoor environment are different from 100 years ago, leading to an increase in complexity. We see (Figure 10):- Climate change resulting in serious energy-efficient measures for the built

environment that can certainly have an effect on health and comfort of the indoor environment.

- Change from family-oriented to multifunctional and divers society.- Individualization/Ageing population leading to other/new needs and demands.- New products and materials leading new emissions and other behavior.

Keeping to our old ways of assessing things, will therefore certainly not be enough. We need to adapt our current assessment and designing methods as well. Well-being (health and comfort) is an important aspect determining the quality of life of an occupant. In late 1980s and during the 1990s, the WHO concept of health, became significant for identifying the concept of a “healthy building” in terms of building performances (i.e., indoor air quality, thermal

16 17

comfort, lighting quality and acoustics). A healthy building is free of hazardous material (e.g., lead and asbestos) and capable of fostering health and comfort of the occupants during its entire life cycle, supporting social needs and enhancing productivity. Human health and comfort needs are recognized as priorities. In addition a healthy building should be ready for the future, adaptable to ‘new drivers’ such as climate change, the change towards a multifunctional and diverse society, the increasing individualisation and the observed change in the type of end-users wishes and demands.

Figure 10 Drivers are different

from 100 years ago (Bluyssen,

2013: figure 8.3).

5. Needs and opportunities

5.1 A different viewTo cope with these gaps and changes we need a different view on IEQ. The current view only considers single-dose relationships. Our current standards are focussed mainly on single-dose responses. With the exception of health-threatening stimuli, the complexity and number of indoor environmental parameters as well as lack of knowledge make a performance assessment using only threshold levels for single parameters difficult and even meaningless.

Most standards are based on averaged data and do not take into account the fact that buildings, individuals and their activities may differ widely and change continuously; not every person receives, perceives and responds in the same way. This is due to physical, physiological and psychological differences but also to differences in personal experience, context and situation. Considering both the numerous indoor stimuli and the lack of a solid scientific basis, it appears implausible to make the final and complex integrating step.

Indoor  

environment 

End‐users 

Society 

Regulators 

Construc5on industry 

Climate change: energy efficient buildings 

New products and materials  A

geing & Individualisa:on 

Mul:‐func:onal and divers society 

18

On top of that, in practice these regulations are very difficult to comply with (measurement in homes cannot be performed on a regular base and the concentration as well as the types of for example indoor pollutants may vary widely as a function of both time and space). And it is seen that the indoor environmental quality as experienced by the occupants is often not acceptable and even unhealthy, even if standards and guidelines for those individual environmental parameters are met.

For the assessment of health and comfort risks of people have when staying indoors, it is clear that a different approach or procedure seems inescapable. A ‘different view on IEQ’ could help to better understand the indoor environment and the effects on people. A view in which IEQ is approached in an integrative multi-disciplinary way, taking account of possible problems, interactions, people and effects, focusing on situations rather than single components (Figure 11).

Figure 11 A different view on indoor environment quality (Bluyssen, 2013: figure 7.1).

How we evaluate and respond to our environment does not only depend on the external stressors involved (physical and psycho-social), but also on personal factors and processes that occur over time (memory and learning) influenced by past events and episodes. They all determine the way external stressors are handled at the moment or over time. Indoor environmental (external) stressors that can cause comfort and health effects are represented by the environmental factors and psycho-social factors, such as working and personal relationships, as well as factors such as sex, whether we smoke, genetics, age, etc. It is clear that all relevant stressors and factors of influence that may affect well-being can be potentially important to consider when an attempt is made to pinpoint the effects caused by different stressors (or combination of stressors). In Figure 12 a compilation of these stressors and factors is presented.

18 19

Environment  Stressors  Effects 

Confounders and modifiers 

Physical 

Psychosocial 

Physical state 

Physiological state 

Psychological state 

Physical 

Psychosocial 

Characteris:cs building, 

systems and rooms 

Characteris:cs built 

environment 

Processes to maintain 

and operate 

Characteris:cs and 

processes of the psycho‐

social working 

environment 

Ligh:ng 

Thermal comfort 

Noise 

Air quality 

Ergonomics 

Discrete and chronic 

events:  

At work 

During commu:ng 

At Home 

(perceived) health ‐ 

symptoms 

(perceived) comfort – 

complaints 

Behaviour 

Mood ‐ emo:onal state 

Traits ‐ personality 

Nervous system 

Immune system 

Endocrine system 

States and traits 

Other Personal factors 

Other factors 

Past exposures& episodes – 

learning effects 

Past and future events – 

behavioral condi:oning 

Figure 12 Stressors, factors, causes and effects

(Bluyssen, 2013: figure 4.1).

5.2 Other assessment methods and indicatorsAs a consequence, besides a different view on IEQ, it is important to consider other assessment methods and indicators. Other indicators that can be related to health and comfort of occupants. Moreover, indicators that can be used to turn negative effects around into a positive experience. If we are serious about improving the indoor environmental quality, indoor stressors are important as a means to prevent possible harm but opportunities to contribute in a positive manner, should not be overlooked. Methods applied in IEQ investigations vary from an epidemiological approach, in which questionnaires and health/comfort data may be used either in combination or not with biomarker sample collection (e.g. blood, urine), field studies in which in general a smaller sample of persons is studied in combination with environmental inventories, to laboratory studies in which persons or animals are exposed to controlled environmental conditions. Health and comfort data are then combined with information on characteristics of the indoor environment in order to find relations. However, other risk factors that may cause psychological or physiological stress (e.g. major life events), individual differences caused by

20

personal factors (e.g. states and traits), or history and context can all affect the outcome that is being studied. These factors are taken into account only to a limited extent in current methods commonly applied to identify relationships between health and comfort of people and the physical environment.

It is clear that methods focused on the control of single environmental factors with the so-called dose or environmental indicators are not enough. To recall: we have three categories of indicators that can be used: the occupant or end-user, the dose or environmental parameter and the building and its components. In the category building and it components certain measures or characteristics of a building, so-called short cuts have been used. In a short-cut, the building characteristics (such as having an HVAC system) or measures taken (such as a maintenance or cleaning schedule) are directly related to comfort or health responses of occupants. And in the category occupants, emphasis is being put on indicators that can give us information on the effects of stress. Indicators that can tell us something on changes in the bodily systems and experience of people are being searched for. People have been directly asked how they experience their environment (mood profiling), panels of trained persons have been used to evaluate air quality (for example from a air filter), assessments with fMRI (functional magnetic resonance imaging) scans to measure changes in blood flow in the brain have been made, and even assessments at cell level such as gene profiling are showing potential as an indicator to be used (Figure 13).

Figure 13 Potential methods for IEQ assessment (Bluyssen, 2013).

(Sources: Tom Hartley, Department of Psychology, The University of York; Hans A.R.

Bluyssen: www.lhmg.amu.edu.pl; P.Desmet, Faculty of Industrial Design, TU Delft)

fMRI-scan: blood flow (Tom Hartley))

Questionnaire: mood (P. Desmet)

Cell-level: gene expression (Hans Bluyssen)

Smelling a filter (P.Bluyssen)

20 21

5.3 A practical approachIt is also clear that we cannot wait until we fully understand all the interactions or mechanisms taking place between the sources that produce/cause the stimuli, among the stimuli, and between the stimuli and the exposed persons. To be able to perform a situational analysis, not only the right package of information is required but also the ‘right’ model or algorithm. A model that is suitable for determining patterns and interactions, and take account of dynamic behaviour.

The built indoor environment is considered a system with sub-systems that do matter, but the system will only function if all sub-systems (components) are optimised along with the total system, whether this is related to health, comfort or sustainability issues (see Figure 14). ‘Systems thinking’ is contextual (Capra, 1996). Translating this thinking to the built environment, this means that situations or scenarios are important. People differ in their responses, environments differ in their conditions. For different scenarios, different interactions occur between different factors of importance. Patterns of factors or indicators seem therefore important to identify, even though those patterns are likely to change over time, creating new patterns. To be able to understand the patterns of concern in the built environment, different scenarios thus need to be studied. Other important aspects of patterns and their interactions, are the feedback concept and the fact that the relationships in a network pattern are in general nonlinear. A network pattern is capable of self-organization.

Figure 14 The Building as a system (Bluyssen, 2013: figure 9.1).

More than 40% of our residential buildings have been constructed before the 1960s, when energy building regulations were very limited. Due to their age most of them require retrofitting or refurbishment. Retrofitting has been identified as the most immediate and cost effective mechanism to reduce

22

energy consumption and carbon emissions in the building and construction sector (E2APT, 2010). Moreover, to meet EU energy performance targets set by the 2007 Energy Action Plan and the 20-20-20 targets adopted, it is necessary to double or triple the current retrofitting rate of 1.2 to 1.4 % to reach the short and long term goals of an energy reduction of 20% by 2020 and a CO2

emissions reduction of between 80-95% by 2050 (EU, 2010). So, we are in need for a practical approach! We have no time to waste.

5.4 Different roles and processesThe challenge of today lies in the accomplishment of sustainable and low-energy built environment and at the same time healthy, comfortable, accessible and safe built environment. Health and sustainability are interrelated in many ways.

In the built environment a major reduction of the fossil fuel consumption should be achieved in order to meet the Kyoto targets. The existing stock is however, far from the currently discussed low-energy standards. Additional, the path towards future low- energy use, or even energy autonomy or energy-positive buildings is seriously hampered by the fear of introducing a negative impact on human health. No consensus understanding of this relationship between energy efficiency and IEQ exists.

This emerging fact, requires a multidisciplinary interactive top-down approach to facilitate the (re)design, construction, maintenance and operation of an indoor environment, in which the architect as well as the other stakeholders fulfil a new or different role. There is a need for a set of optimised processes that can be applied throughout the life cycle of the systems created by humans through the involvement of all interested parties (stakeholders) with the ultimate goal of achieving customer satisfaction. The different processes, which need to be coordinated and communicated properly, can help to identify goals and objectives, stakeholders and their values, risks and opportunities, and possible solutions, methods and measures to be taken. An interactive top-down approach allows for a holistic and integrative management during the entire life-cycle of a building from initiation to breakdown. Holistic, in this perspective, means focused on the requirements of the end-user, in such a way that all aspects and interactions between end-user and environment and the other way round, are taken into account.

22 23

6. AmbitionMy ambition is to establish an integrated research & education programme on Understanding and managing the indoor environment, in which is dealt with all the needs presented, in due time. A programme for future architects that can help them to fulfill the required multidisciplinary coordinating role in the building industry on the one hand and the creation of truly sustainable buildings during the whole life-cycle on the other. The development of an integrated approach towards risk assessment of indoor environment quality, based on the assumption that the indoor environment is more than the sum of its parts, and that its assessment has to start from human beings rather than benchmarks (of single-dose relationships), will form the basis to realize this ambition.

To accomplish the integrated research and educational programme, one of the first steps to be taken will be the creation of a ‘Senselab’: a semi-lab environment in which people, students, teachers, researchers, but also the general public, will be able to experience different environmental conditions in order to better understand the indoor environment.

6.1 ResearchThe answering of the following questions can contribute to this understanding of the indoor environment:1. Mechanisms - Human model: How and when do people respond to ex-

ternal stressors? To be more successful in determining the health and comfort effects of certain indoor environmental aspects it seems essential to understand the mechanisms behind how and why people respond to external stressors.

2. Assessment - indicators: Which parameters or indicators and assessment methods can be used to explain the effects or responses? The next step is then to determine which parameters or indicators can be used to explain these responses and how to assess those. When the picture is more clear, procedures can be improved in such a way that the chances to successfully assess the effects caused by different stressors (or combination of stressors) increase.

3. Analysis - risk/opportunity model: Is it possible to define a risk/opportunity model for health and comfort in the indoor environment? Depending on the scenario and the profile of the occupant of concern, patterns and interactions of cause-effect relationships need to be established, starting with the indicators of both causes and effects and the assessment protocols. To be able to perform such a situational analysis, the ‘right’ model or algorithm is required.

24

4. Practical approach - framework/verification matrix and a set of processes: What do we need to make optimal choices, also in relation to other values (e.g. sustainability, affordability), which can be implemented efficiently?

6.2 EducationNext to this understanding of the indoor environment, we also need to make ‘others’ understand that indoor environment and make certain, the knowledge acquired is implemented in the right way. Two books have been written to support this creation of awareness and will be made available for the educational programme at bachelor and/or masters level:- The Indoor Environment Handbook - How to make buildings healthy and

comfortable (Bluyssen, 2009).- The Healthy Indoor Environment - How to assess occupants’ wellbeing in

building (forthcoming) (Bluyssen, 2013).

I strongly believe a multi-disciplinary approach is needed in the building industry to create sustainable buildings. At national, European and world-wide level, it is acknowledged that a healthy and comfortable indoor environment is important for the quality of life, now and in the future. The architect will need to have a more than ever coordinating role in this approach as the overall systems engineer, with a basic multi-disciplinary knowledge and integrating capabilities. This new role requires a multi-disciplinary educational program with strong cooperation within and outside of the university.

24 25

ReferencesBluyssen, P.M., Oliveira Fernandes, E. de, Groes, L., Clausen, G.H., Fanger, P.O., Valbjørn, O., Bernhard, C.A., Roulet, C.A. (1996) European Audit project to optimize indoor air quality and energy consumption in office buildings, Indoor Air Journal 6: 221-38. Bluyssen, P.M. (2009) The Indoor Environment Handbook: How to make buildings healthy and comfortable, Earthscan, London, UK. Bluyssen, P.M., Richemont, de S., Crump, D., Maupetit, F., Witterseh, T., Gajdos, P. (2010) Actions to reduce the impact of construction products on indoor air: outcomes of the European project HealthyAir, Indoor and Built Environment 19: 327-39.Bluyssen, P.M., Aries, M., van Dommelen, P. (2011) Perceived comfort in office buildings: the European HOPE project, Building and Environment 46: 280-8.Bluyssen, P.M. (2013) The healthy indoor environment: How to assess occuppants’ wellbeing in buildings, Taylor & Francis, forthcoming by Earthscan from Routledge.Bonnefoy, X.R., Annesi-Maesona, I., Aznar, L.M., Braubachi, M., Croxford, B., Davidson, M., Ezratty, V., Fredouille, J., Ganzalez-Gross, M., van Kamp, I., Maschke, C., Mesbah, M., Moisonnier, B., Monolbaev, K., Moore, R., Nicol, S., Niemann, H., Nygren, C., Ormandy, D., Röbbel, N., and Rudnai, P. (2004) Review of evidence on housing and health, Fourth Ministerial Conference on Environment and Health, Budapest, Hungary, 23-25 June 2004.Capra, F. (1996) The Web of Life: A new scientific understanding of living systems, New York: Anchor books.De Dear R. and Brager, G. (2002) Thermal comfort in naturally ventilated buildings: revisions to ASHRAE standard 55, Energy and Buildings 34 (6).E2APT (2010) The fundamental importance of building in Future EU Energy Savings Policies, Energy Efficiency Action Plan Taskforce of the Construction Sector (Assessed at October 29, 2012) http://euroace.org/LinkClick.aspx?fileticket=IYFmSEm7faM%3D&tabid=159EU (2010) Towards a new energy strategy for Europe 2011-2010, Council document http://ec.europa.eu/energy/strategies/consultations/doc/2010_07_02/ 2010_07_02_energy_strategy.pdf. Assessed at October 29, 2012.Fisk, W.J., Lei-Gomez Q., M.J. Mendell (2007) ‘Meta-analysis of the associations of respiratory health effects with dampness and mold in homes’, Indoor Air, 17(40), 284-296.Hawkes, D. (2008) The environmental imagination, technics and poetics of the architectural environment, Routledge, Taylor & Francis group, UK.Hinson, J., Raven, P., Chew, S. (2010) The endocrine system, second edition, Systems of the body, Churchill livingstone Elsevier, printed in China.

26

Houtman, I., Douwes, M., de Jong, T., et al. (2008) New forms of physical and psychological health risks at work, European Parliament, Policy depart- ment Economic and scientific policy, IP/A/EMPF/ST/2007-19, PE 408.569, Brussels, Belgium.Lewtas, J. (2007) Air pollution combustion emissions: Characterization of causative agents and mechanisms associated with cancer, reproductive, and cardiovascular effects: The Sources and Potential Hazards of Mutagens in Complex Environmental Matrices - Part II. Mutation Research/Reviews in Mutation Research 636, 95-133.Marken Lichtenbelt, van W.D., Vanhommerig, J.W., Smulders, N.M., Drossaerts, B.S., Kemerink, G.J., Bouvy, N.D., Schrauwen, P., Teule, G.J.J. (2009) Cold-activated brown adipose tissue in healthy men, The New England Journal of Medicine, 360: 1500-8.Miedema, H.M.E., Vos H. (2003) Noise sensitivity and reactions to noise and other environmental conditions, J. Acoust. Soc. Am. 113: 1492-1504.Pallasmaa, J. (2005) The eyes of the skin, Academic editions, London, 1996. Revised edition, Wiley Academy, Chichester, UK.

26 27

Personal noteA very long time ago, I was born and raised in Nijmegen with a father at the physics department of the University of Nijmegen, and a mother as an independent artist. Perhaps this combination of their mathematics and art genes, made me choose Architecture and Building engineering in Eindhoven. Who knows.

Although initially, my dream was to design and create modern buildings and furniture ala Corbusier, inspired by lectures of Professor Vorenkamp on the thermo-physiological models of big names such as Gagge, Fanger and Stolwijk, I managed to get my further education with at least two of those big names: Stolwijk during a working period at Yale University and Fanger at the Technical University of Denmark, where I received my PhD on air quality evaluated by a trained panel. Just before my time in Denmark came to an end, I was scouted by TNO at an Indoor Air conference in Toronto, Canada, and a few months later I started in Delft as a young researcher, which to my surprise is more than 22 years ago. At TNO, the management of multi-partner & multi-disciplinary EU R&D projects became my speciality, set-off by the First EU funded project on indoor air quality and energy consumption, in which a trained panel of people to evaluate the indoor air quality was applied in 56 office buildings all over Europe. This project was not only the first EU funded project in this area, but it brought about a lot of interest. The Press got literally wild by the idea of using a trained panel to evaluate indoor air quality. They came from all over the place to interview and to even film. The wall street journal, het Parool, NRC, Telegraaf, radio and television: Beyond 2000 from Australia, Astrid Joosten from the Netherlands, The European Journal….you name it.

At TNO I got the opportunity to extend my knowledge in assessment of indoor environment quality, not only indoor air quality but also other aspects of that indoor environment, during more than twenty years in numerous EU projects. I got experienced in knowledge management and road mapping, in the Center of Building and Systems (a cooperation between the Technical university of Eindhoven and TNO), but also at European Level, assisting with the creation of the first contours of the European Construction Technology Platform and later the E2B (Energy efficient building) platform. And I got the opportunity to be part of knowledge transfer or rather valorization of the knowledge gained in standardization work at European level for which I was hired by the former named Ministry of Housing, Spatial planning and the Environment. Which was not easy I can tell you. It is a profession in itself. What turned out to be much less complex was the writing of the award winning book The Indoor environment

28

handbook: How to make buildings Healthy and comfortable. The book I had wanted myself when I was studying Architecture and Building engineering.

At the end of 2011, by coincidence, I noticed an advertisement for a female fellowship at the website of the TU Delft. I figured, if you don’t try you will never win, so I sat down and wrote my ideas down. Less than half a year later, at May 15 to be exact, I was appointed! And from October 1, 2012 I started as a ‘young’ professor, which deep in my heart has been my dream since I was very young.

I would like to thank the Delft Technology fellowship for Top female scientists that they created the chair Indoor Environment. I feel very fortunate to got the opportunity to be part of this initiative. And then of course I would like to thank all my old colleagues from TNO, and new colleagues from The Delft University of technology, but also all those other colleagues all around the world, who gave me the inspiration and strength in the last two decades or so, to keep going in the direction I have sketched in this booklet. Also thanks to my father and mother who have always supported me no matter what, my brother Hans who will soon also accept the same title in Poland, my family and friends. But it is without doubt to say, that my husband and children suffered the most from this time consuming ‘hobby’: doing research, writing books, etc. Because that’s how I see it most of the time. Without their support and endurance, it wouldn’t have been possible to even spend all those so-called ‘free’ hours you need. Especially my husband Darell Meertins should receive an award for his patience. A special thanks also to my two sons, Anthony and Sebastian, who not only gave me the opportunity but also gave me a couple of their artworks to use!

Thank you all.

I have spoken / Ik heb gezegd.

28

Faculty of ArchitectureJulianalaan 1342628 GA DelftThe Netherlands

Tel: +31 (0)15 27 89805

www.tudelft.nl