Can light reflection from glass curtain walls cause light pollution?

The light reflection of glass curtain walls contributes to light pollution.

Chinese name: light pollution

English name: light pollution

Definition 1: The phenomenon of excessive light radiation causing adverse effects on human life and production environment. Including pollution caused by visible light, infrared rays and ultraviolet rays.

Light pollution in a broad sense includes things that may have adverse effects on people's visual environment and physical health, including the reflections of common books and papers in life, wall paints and even the "glow" of colorful roadside advertisements. It can also be included in this list, which shows the wide range of light pollution. In daily life, common light pollution conditions are mostly the dizziness of pedestrians and drivers caused by the reflection of mirrored buildings, and the discomfort caused by unreasonable lighting at night to the human body.

What is light pollution?

The problem of light pollution was first raised by the international astronomical community in the 1930s. They believed that light pollution was caused by the brightening of the sky caused by outdoor lighting in cities, which negatively affected astronomical observations. influence. At present, there is no clear definition of light pollution at home and abroad. It is generally believed that light pollution generally refers to various types of light that affect the natural environment, adversely affect human normal life, work, rest and entertainment, impair people's ability to observe objects, cause discomfort to the human body and damage human health. Light radiation with wavelengths from ten nanometers to one millimeter, that is, ultraviolet radiation, visible light and infrared radiation, may become sources of light pollution under different conditions.

Classification

Based on different classification principles, light pollution can be divided into different types. Internationally, light pollution is generally divided into three categories, namely daylight pollution, artificial daytime and colored light pollution.

White pollution

When the sunlight is strong, the glass curtain walls, glazed brick walls, polished marble and various paints and other decorations of buildings in the city reflect light, making them bright and dazzling. Eye-catching. Expert studies have found that people who work and live in white light polluted environments for a long time will suffer varying degrees of damage to the retina and iris, and their vision will drop sharply, with the incidence of cataracts as high as 45%. It can also make people dizzy and upset, and may even lead to insomnia, loss of appetite, depression, physical weakness and other symptoms similar to neurasthenia. In summer, the strong reflected light from the glass curtain wall enters nearby residential buildings, increasing the indoor temperature and affecting normal life. Some glass curtain walls are semicircular, and the reflected light can easily cause fires. Drivers driving under the scorching sun will be unexpectedly hit by the light reflected from the glass curtain wall, and their eyes will be strongly stimulated, which can easily cause a car accident. According to research by optical experts, the reflected light from mirrored building glass is more intense than sunlight, with a reflectivity as high as 82% to 90%. Almost all light is reflected, which is far beyond what the human body can bear. People who work and live in a polluted environment with white light for a long time can easily suffer from vision loss, dizziness, insomnia, palpitations, loss of appetite, depression and other symptoms similar to neurasthenia, which can cause changes in people's normal physiology and psychology. In the long run, it can induce certain diseases. In summer, strong reflected light from glass curtain walls enters nearby residential buildings, destroying the original good indoor atmosphere and raising the room temperature by an average of 4°C to 6°C. affect normal life.

Glare pollution

Light pollution

The headlights used for lighting when cars are driving at night and unreasonable lighting arrangements in factories can cause glare. In some workplaces, such as train stations and airports, as well as central control rooms of automation companies, excessive and overly complex signal light systems can also cause a decrease in visual acuity of workers, thus affecting work efficiency. The strong light generated by the welding gun can also damage people's eyes without appropriate protective measures. Workers who work under strong light conditions for a long time (such as smelters, melters, glass blowers, etc.) will also suffer eye damage due to strong light.

Artificial daylight

After night falls, the advertising lights and neon lights on shopping malls and hotels are dazzling and dazzling. Some strong beams of light even reach into the sky, making the night look like daytime, which is the so-called artificial daylight. In such a "city that never sleeps", it is difficult to fall asleep at night, disrupting the body's normal biological clock, resulting in low work efficiency during the day. Artificial daylight can also harm birds and insects, and strong light may disrupt the normal reproduction process of insects at night.

At present, the excessive use of lights in big cities makes the sky too bright and makes stars invisible, which affects astronomical observation, aviation, etc., and many observatories are forced to stop working as a result. According to astronomical statistics, when the sky is not polluted by light at night, about 7,000 stars can be seen. However, in big cities with street lights, background lights, and landscape lights, only about 20 to 60 stars can be seen.

Colored light pollution

Dance halls, night light pollution

The black light lamps, rotating lights, fluorescent lamps and flashing colored light sources that are always installed constitute colored light pollution. According to measurements, the intensity of ultraviolet rays produced by black light lamps is much higher than that of ultraviolet rays in sunlight, and its harmful effects on the human body last for a long time. If people are exposed to this kind of radiation for a long time, it can induce nosebleeds, tooth loss, cataracts, and even lead to leukemia and other cancers. Colored light sources dazzle people, which are not only harmful to the eyes, but also interfere with the central nervous system of the brain, making people feel dizzy, causing nausea, vomiting, insomnia and other symptoms. Scientists' latest research shows that colored light pollution not only damages people's physiological functions, but also affects people's psychology. The "Spectral Photochromatic Effect" measurement shows that if the psychological impact of white light is 100, then blue light is 152, purple light is 155, red light is 158, and black light is the highest, 187. If people are exposed to colorful lights for a long time, the psychological accumulation effect will also cause physical and mental illnesses such as fatigue, dizziness, neurasthenia, etc. to varying degrees. In addition, some scholars also divide light pollution into "outdoor visual environmental pollution", "indoor visual environmental pollution" and "local visual environmental pollution" based on the scope of the impact of light pollution. Among them, outdoor visual environmental pollution includes building exterior walls, outdoor lighting, etc.; indoor visual environmental pollution includes indoor decoration, poor indoor light and color environment, etc.; local visual environmental pollution includes books, paper, and certain industrial products.

Laser pollution

Laser light pollution

Pollution is also a special form of light pollution. Because laser has the characteristics of good directionality, concentrated energy, and pure color, and after the laser passes through the focusing effect of the human eye lens, the light intensity when it reaches the fundus can increase hundreds to tens of thousands of times, so the laser has a greater impact on the human eye. harmful effects. Part of the laser spectrum belongs to the ultraviolet and infrared ranges, which can damage the conjunctiva, iris and lens of the eye. High-power lasers can harm the deep tissues and nervous system of the human body. In recent years, lasers have been increasingly used in medicine, biology, environmental monitoring, physics, chemistry, astronomy and industry, and laser pollution has attracted more and more attention.

Infrared pollution

In recent years, infrared rays have been increasingly used in military, artificial satellites, industry, health, scientific research, etc., so the problem of infrared ray pollution has also arisen. Infrared ray is a kind of thermal radiation that can cause high temperature damage to the human body. Strong infrared rays can cause skin damage, which is similar to scalding. It starts with burning pain and then causes burns. There are several different types of damage to the eyes caused by infrared rays. Infrared rays with a wavelength of 7500 to 13000 angstroms have a high transmittance to the cornea and can cause damage to the retina of the fundus. In particular, infrared rays near 11,000 angstroms can protect the front media of the eye (cornea, lens, etc.) from damage and directly cause retinal burns in the fundus of the eye. Infrared rays with wavelengths above 19,000 angstroms are almost completely absorbed by the cornea and can cause corneal burns (turbidity, white spots). Most of the energy of infrared rays with wavelengths greater than 14,000 Angstroms is absorbed by the cornea and intraocular fluid and cannot penetrate the iris. Only infrared rays below 13,000 Angstroms can penetrate the iris and cause iris damage. Cataracts may occur if the human eye is exposed to infrared rays for a long time.

Ultraviolet pollution

Ultraviolet rays were first used in disinfection and certain processes. In recent years, its scope of use has been continuously expanded, such as for the detection of the ground by artificial satellites. The effects of ultraviolet light vary according to its wavelength. The vacuum ultraviolet part with a wavelength of 1000 to 1900 angstroms can be absorbed by air and water; the far ultraviolet part with a wavelength of 1900 to 3000 angstroms can mostly be strongly absorbed by biological molecules; the wavelength is The near-ultraviolet part between 3000 and 3300 angstroms can be absorbed by certain biomolecules. Ultraviolet rays mainly damage the cornea and skin of the human body. The ultraviolet rays that cause corneal damage are mainly in the range of 2500 to 3050 angstroms, and the wavelength of 2880 angstroms has the strongest effect. Repeated exposure of the cornea to UV rays does not increase its tolerance to UV rays.

The damaging effects of UV rays on the cornea manifest as an extremely painful white spot injury called photophobic ophthalmia. In addition to severe pain, it causes tearing, blepharospasm, conjunctival hyperemia, and ciliary muscle twitching. The main damage caused by ultraviolet rays to the skin is erythema and small blisters. In severe cases, it can cause epidermal necrosis and peeling. The skin on the chest, abdomen and back of the human body is the most sensitive to ultraviolet rays, followed by the forehead, shoulders and buttocks, and then the soles of the feet and the back of the hands. Different wavelengths of ultraviolet rays have different effects on the skin. Ultraviolet rays with wavelengths of 2800 to 3200 angstroms and 2500 to 2600 angstroms have the strongest effects on the skin.

Light pollution in a broad sense also includes

Visual pollution refers to the cluttered visual environment in urban environments. For example, there are messy electrical wires, phone lines, messy garbage, messy stalls and colorful advertising posters on both sides of the city streets. There are many other ways to classify light pollution. For example: In Wikipedia, we see that light pollution is divided into the following categories: Light trespass (light intrusion). This kind of "pollution" mainly refers to excessive light sources that affect other people's daily rest. . For example, lights at night make it difficult to sleep, etc. At present, various countries already have relevant laws to protect their people from infringement. Over-illumination (over-illumination) Over-illumination is mainly a waste caused by the meaningless use of energy. The energy wasted in the United States due to "excessive lighting" every day is equivalent to 2 million barrels of oil! Clutter (mixed light) Different types of light sources are mixed together, which will seriously affect the passive recipient. and may cause a car accident. What’s even more frightening is that pilots flying at night need to spend energy finding and identifying aviation signals among these various lights. Glare A bright light in the dark. It will cause temporary "visual loss" to pedestrians or drivers, leading to traffic accidents. Moreover, if not properly protected, this glare can also damage people's vision. Sky glow (artificial daytime phenomenon) Artificial daylight will seriously affect the work of astronomers and cause damage to the ecological environment. In short, light pollution can lead to a waste of energy and damage people's physical and mental health. In addition, excessive light pollution will seriously damage the ecological environment and have a negative impact on traffic safety and aerospace scientific research. Before the government makes effective adjustments to light sources, we must pay attention to staying away from similar sources of pollution. Ma Jianze, a professor at Tianjin University in my country, uses the occurrence and impact time of light pollution as the classification standard. He divides light pollution into "daylight light pollution" and "nightlight light pollution". The white light pollution mentioned above belongs to daylight light pollution, artificial daytime and colored light pollution. It belongs to luminous light pollution. No more details will be said here about this classification method.

Hazards

Light pollution prevents one-fifth of the world’s people from seeing the Milky Way

According to a latest survey in the United States, light pollution caused by bright lights at night has blinded one-fifth of the world's population to the Milky Way. Elwich, one of the authors of the survey report, said: "Many people have lost the night sky, and it is our lights that eclipse the night sky." He believes that about two-thirds of the world's people now live in light pollution. In the night sky in the suburbs far away from the city, you can see more than 2,000 stars, but in big cities you can only see a few dozen. In Europe, America and Japan, the problem of light pollution has long attracted people's attention. The United States has also established the International Dark Sky Association to combat light pollution.