Aydınlatma Tasarımının Kullanıcı Üzerindeki Fizyolojik Ve Psikolojik Etkileri Açısından İncelenmesi

Abstract

Yaşamın döngüsünün devamı ve insanın günlük gereksinimlerini yerine getirebilmesi için ışığa gerek duyulur. Günışığının yetmediği zamanlarda insanların görsel ihtiyaçlarını yerine getirebilmesi için yapma aydınlatma sistemlerinin tasarlanması gerekir. Aydınlatma tasarımının öncelikli amacı farklı görevleri yerine getirebilecek, mekân ve nesneleri algılayabilecek görsel koşulların; kısacası görsel konfor koşullarının sağlanmasıdır Görsel konfor, ışığın nicelik ve niteliğine bağlıdır. Işığın niceliği yani gerekli aydınlık düzeyleri her bir aktivite için standartlara göre belirlenir. Işığın kalitesi ise ışığın doğrultusu, renk, renksel geriverim ve aydınlığın düzgünlüğünü içerir. Günışığı mükemmel kalitededir ve yapma aydınlatmanın spektrumu mümkün olduğunca doğal ışığa yakın olmalıdır. Aynı zamanda göz sağlığının korunması ile de ilişkilidir. Işık sadece görmemizi sağlamaz aynı zamanda sağlığımız, biyolojik ritmimiz, ruh halimiz, iyi hissetmemiz ve performansımız üzerinde de etkilidir. Bu çalışmada aydınlatma tasarımının kullanıcılar üzerindeki fizyolojik ve psikolojik etkileri incelenmiştir. Öncelikle aydınlatmanın yararları ve temel aydınlatma kavramları ele alınmıştır. Bu bölümdeki bilgiler ağırlıklı olarak standartlar ve aydınlatma ile ilgili temel kaynaklar incelenerek derlenmiştir. 3.bölümde ışık kaynakları, aygıtlar ve bunlar kullanılarak tasarlanan aydınlatma sistemleri üzerinde durulmuştur. Bölüm 4.1 de ışık ve sağlık ilişkisine yer verilmiş, ışığın sirkadiyen ritim, performans ve ruh hali üzerindeki etkileri incelenmiştir. Bölüm 4.2 aydınlatmanın hem fizyolojik hem de psikolojik etkilerini göz önüne alarak geliştirilmiş olan Ergonomik Aydınlatma Göstergesi -ELI programı ve ofis yapıları için programın kullanımı hakkında bilgi vermektedir. Bölüm 4.3 de aydınlatma tasarımını ergonomik olarak değerlendiren ELI kriterlerinin bir önceki bölümlerdeki başlıklarla olan ilişkisi yorumlanmış ve önerilerde bulunulmuştur. Sonuç bölümünde ışık ve sağlık ilişkisine tekrar değinilmiş, aydınlatma tasarım bilincinin Türkiye deki durumundan bahsedilmiş ve sadece fizyolojik koşullara göre değil ışığın psikolojik etkilerine göre aydınlatma sistemlerinin tasarlanmasının öneminden bahsedilmiştir.

The light is required for the cycle of life and to perform people s daily needs. When natural light is not enough in a space, artificial lighting systems should be designed for people s visual activities. The primary objective of the lighting design is providing the visual conditions that can enable to perform different visual tasks and perceive of place and objects, briefly visual comfort conditions. Visual comfort depends on the quantity and quality of light. The lighting quantity so required light level is determined for the particular activity according to standards. The quality of light includes the direction and colour of light, colour rendition, illuminance uniformity. Daylight has excellent quality and the light spectrum of artificial light should be as close as possible to that of natural light. Besides, it is related with the protection of eye health. Light not only enables people to see; it also affects on our health, biological rhythm, mood, sense of wellbeing and performance. In this study the physiological and psychological effects of lighting design on user has been analyzed. Firstly, the benefits of lighting and basic lighting concepts have been discussed. The information in this chapter is compiled to mainly research standards and key resources that related to lighting. The lighting sources, fixtures and the lighting systems that are designed using these components have been emphasized in the chapter 3. The relation between light and health are featured and the effects of light on circadian rhythm, performance and mood are examined in the chapter 4.1. The link between daylight and human health is becoming increasingly clear. Daylight can have health effects on skin, eyes, hormone secretions, and mood. Essentially daylight stimulates the production of vitamin D, an essential element for maintaining a healthy immune system and plays a major role in the control of our circadian rhythm - the cycle that regulates our body’s sleep at night and alertness during the day. Its temporal variation may be used to combat jet lag and sick building syndrome. During the evolution of life on earth, with its sunlight characteristic spectrum and variations between day and Night life has had a decisive impact on most existing Their forms and their adaptation to natural environments. As a direct consequence of this, humans display a including circadian rhythm of approximately 24 hours, amongst other things, sleep and wakefulness, body temperature, metabolism, hormone production, and fluctuations in attention and behavior. Light sends signals via the novel photoreceptor cells and a separate nerve system to our biological clock, which in turn regulates the circadian (daily) and circannual (seasonal) rhythms of a large variety of bodily processes. The hormones cortisol (“stress hormone”) and melatonin (“sleep hormone”) play an important role in governing alertness and sleep. Cortisol, amongst others, increases blood sugar to give the body energy and enhances the immune system. The level of the sleep hormone melatonin drops in the morning, reducing sleepiness. For good health, it is of importance that these rhythms are not disrupted too much. In case of a disruption of the rhythm, bright light in the morning helps restoring the normal rhythm. Light is essential to enable vision. Photoreceptors in the human eye pick up the contrast and colour of light emanating from the objects around us, and this is translated into images in the visual cortex of the brain. Windows are highly valued for their views of the natural environment and for their connection to the outdoors. Movement and changes in light levels throughout the day can be mentally restful or stimulating. Views of landmarks or scenes can give a sense of place. Time of day, weather conditions, and personal safety conditions can be determined by a glance out the window. Interiors without sufficiently large side windows and without clear or lightly tinted glass can cause claustrophobia. Lack of daylight has been linked to ‘sick building’ syndrome, with some research showing a direct link between a worker’s distance from the window and symptoms of illness. A 1998 World Health Organization report noted that up to 30% of new and remodeled buildings worldwide may be linked to health problems. ‘Sick Building Syndrome ’ (SBS) is a term used to describe situations in which building occupants experience discomfort and even acute health problems that appear to be related to time spent in the building, even when no specific illness or cause can be identified. The incidence of illness is significantly higher in some buildings than in others. The symptoms that characterize ‘sick building syndrome’ are sore eyes, running nose, headaches, mucous membrane irritation, dry skin, dizziness and nausea. No single, specific cause has been found. It is believed that the syndrome is caused by a combination of poorly adjusted ventilation, air conditioning, temperature, humidity and lighting and psychological factors such as stress, management style and tedious work schedules. In some climates, daylight systems that provide more illuminance during the winter and less during the summer (in inverse proportion to daylight availability) are considered more desirable, to counter the effects of seasonal affective disorder. Our chronobiological rhythms are also influenced by summer and winter. In the dark months of the year, we tend to be less fit, we have difficulties concentrating and our responses are slower. We also eat more, so our body weight increases and blood sugar levels rise. The seasonal depression often found among people living in northern latitudes and typically referred to as Seasonal Affective Disorder (SAD) is a commonly known effect of light that is related to our endocrinal system. The term was first used by Dr Norman E. Rosenthal in 1981 to describe the depression brought about by lack of daylight. SAD is an emotional disorder characterized by drastic mood swings, lowered energy, and depression. Studies have also found that the colour of lighting can have an effect on a persons’ mood and work performance. The productivity of an individual or an organization can be defined as the ability to enhance work output through increases in either quantity and / or quality of the product or service to be delivered. There are three routes by which lighting conditions can influence the performance of individuals: through the visual system, through the perceptual system and through the circadian system. The capabilities of the determined by the lighting conditions are visual system. The state of the circadian system is influenced primarily by the light - dark cycle. The message delivered by the perceptual system is influenced by many factors, lighting being just one of them. In the chapter 4.2 provide information about The Ergonomic Lighting Indicator (ELI) which has been developed to consider both physiological and psychological effects of lighting and introduction using of program for office buildings. Zumtobel, encouraged and supported by intensive research activities, has made lighting quality measurable for the first time ever. The Ergonomic Lighting Indicator (ELI) now makes it possible to express lighting quality, in all its diversity, in figures, showing a total of five aspects of quality: visual performance, vista, visual comfort, vitality and empowerment are shown in a spider chart which comprises five axes. This assessment system makes it possible to make even complex design parameters apparent at a glance. Quality criteria and assessment methods were developed in close cooperation with Professor Christoph Schierz (Swiss Federal Institute Of Technology Zurich). These were used to produce simplified questionnaires regarding practical day-to-day work. Light for visual functions; people need a minimum level of light in order to perform visual tasks and identify objects. This level varies greatly depending on the particular application area. The visual demands made by an office are different to those of a retail area, and discussions require different lighting qualities than working at a PC. For many areas and activities, these basic visual requirements are summarized in standards and recommendations concerning brightness, uniformity, glare limitation, colour and contrast rendition. Light which has an emotional effect; relaxing or working, stimulating or calming: the various ways in which light can be used to evoke emotions matches the whole gamut of human emotions. For instance, a room is much more inviting if light is used to attractively illuminate the vertical surfaces and objects in the room. Colors also produce significant effects. Light which has a biological effect; nature provides the perfect model for using light to achieve biological changes. Daylight has left its imprint on humans. The succession of light and darkness is reflected in our waking and sleeping patterns and hence our circadian rhythms. A light spectrum with sufficient blue components inhibits the production of melatonin, and has a favourable effect on alertness and readiness for action in the morning and early afternoon. Warm colors in the evening interfere with melatonin production and favour relaxation. The relation between ELI criteria, which evaluate lighting design as ergonomic and headlines in the previous chapters are interpreted and made suggestion. In the conclusion, the relation of light and health again are mentioned, the condition s sense of the lighting design in Turkey and the importance of lighting systems are designed not only physiological requirements but also accordingly psychological effects are examined.