Natural lighting: types and main aspects of choice. Coursework: Calculation of natural lighting Types of natural lighting

While reading the text, try to visualize everything that is written. This will help you not get confused in the endless colors and shades, and will also help you understand the article more accurately. In general, go ahead and sing! By the way, who plays what? Please write in the comments - it’s interesting to know what people listen to while surfing the Internet.

Dawn

At dawn the lighting changes very quickly. Natural light has a bluish tint just before sunrise. And if the sky is clear at this time, the effect of a red sunset may be observed. In nature, a combination of high stratus or cirrus clouds with low-lying fog is often found. In such conditions there is a transition sunlight from bottom-up to general more diffused light, in which shadows are blurred. At negative temperatures the effect is more pronounced.

At dawn, you get excellent photos of plants, open landscapes, ponds, and east-facing churches. Often the fog spreads in the lowlands, near the water surface. Valley landscapes look very impressive when photographed from a high point in an eastern direction. It is often at dawn that scenes with equipment, metal structures and any other objects that have a glossy shiny surface are filmed. In natural light, such surfaces and the reflections from them look simply magnificent.

Photographer: Slava Stepanov.

The quality of light in the mountains is determined by location. If the terrain hides the sunrise, it is almost impossible to get interesting lighting effects. It should also be mentioned that dawn is most often calm. This helps to get perfect shots of smooth surfaces of bodies of water.

Natural light in the morning

After sunrise the light changes very quickly. In warm months, the sun can dispel fog or haze, in cold periods it can create it (as a result of evaporation of frost). Weak evaporations from ponds, rivers, and wet roads can be effective. If it rained at night, then in the morning the wet streets and plants, dull under normal conditions, will sparkle with many bright sparkles.

As the distance increases, the landscape blurs and brightens. This can be used to convey the 3rd dimension. During this period of the day, the color of the lighting changes from warm, bright yellow with golden notes to a warmish-neutral tone. In pictures taken in the morning, human skin looks very smooth. The fact is that at night our skin tightens, and in the morning the face seems refreshed - the main thing is to wash it properly.

Photographer: Maria Kilina.

An hour later, the sun has risen, creating ideal lighting for photography. Professional photographers often get up long before dawn in order to have time to prepare for the session and “catch” the optimal light. The weather forecast is almost irrelevant because morning weather is difficult to predict.

There are other reasons to wake up early and get to your shooting location in plenty of time. You will be able to independently monitor weather changes and, based on the position of the sun, understand at what time there will be optimal natural lighting for photographing specific scenes. It is advisable to keep appropriate records. Also do not forget that the observation results will only be valid for a specific time of year.

Noon

The time and duration of ideal light depends on the latitude of the area and the season. In northern regions, where the sun does not set but does not rise too high, this light is observed most of the night and all day. In temperate latitudes, suitable light remains for several hours. But do not forget that in this case the position of the luminary changes. In winter it can be low all day (I’ll talk about this in detail).

Maximum brightness occurs for four hours in the very middle of the day. In the hot summer there are also 4 ideal hours for photography. Two of them are in the afternoon, and two more in the morning. There is a dead period between them. At this time, there is a very high probability of getting overexposed in the photo.

Photographer: Elena Ovchinnikova.

In equatorial and tropical regions, natural light at midday is not suitable for photography. The sun is located high above your head and creates an annoying, blinding light that makes the surrounding landscapes expressionless.

People photography can only be done using fill light through direct additional lighting or reflectors. It is recommended to use light with a color temperature of approximately 5.2 thousand Kelvin.

Midday light in such regions can only be used to photograph canyons and gorges that are densely covered with vegetation. At other times of the day, sunlight does not reach such corners. The presence of direct rays helps the photographer get bright, contrasting images.

Afternoon and evening

When heated during the day, the air absorbs moisture from water or soil. Therefore, in the 2nd half of the day, changes in the spectral composition (color) are observed. natural light, which are not always present in the morning. Warm air absorbs more moisture. Cooling as the sun moves toward sunset, it loses its ability to retain moisture. The latter condenses into invisible tiny drops, which remain in the form of a suspension. When the temperature drops sharply, it becomes foggy. This is especially true in maritime regions.

Usually the fog is very weak and is visually noticeable by the presence of a slight haze, which can “dim” the light. For this reason, summer afternoons can seem dull and gloomy, even if the sun is shining brightly. In photographs this is expressed by “suppressed” colors and tones. As the evening approaches, the situation improves as the sun's rays begin to break through the haze of dust and water particles to reveal an aerial perspective.

Photographer: Maria Kilina.

In the second half of a summer day, the air in the city may look gray. If you look at the city from an airplane, you will notice a haze of light bluish haze around it. It should be taken into account that dust and moisture scatter the rays of natural light. When the sun is high, red rays are absorbed and blue rays are scattered, raising the color temperature. A cold metallic blue appears in the photographs, looking unattractive.

The above partly explains how afternoon light differs from morning light. There are other factors, such as the characteristic orientation of building and other structures in various locations. The same gardens are located in such a way as to capture sunlight as much as possible. Trees and plants take on their final shape, which depends on how the sun's rays hit them. But in general, morning light is more preferable than afternoon light.

Sunset

At sunset, a specific natural light is created, characteristic of the low position of the luminary, when the atmosphere allows the transmission of red long-wave radiation and reflects short-wave blue radiation. During the day, some of the red rays were absorbed by the haze, and the blue rays were scattered. Now the situation is reversed. Top part the sky remains blue because the angle of its illumination has changed. As a result, cool color combinations and smooth tonal gradients.

A sunset can become both a source of light and the subject of photography itself. IN in this case We will consider only the quality of radiation characteristic of this time of day. At sunset, the sun's rays break through the haze or light clouds. Their color gradually warms up (the color temperature decreases).

Many photographers consider this state of the atmosphere to be the most favorable for conveying natural light in the evening and interesting in context color range. If there is a need to make adjustments, this can be done by using blue filters.

Premises with constant occupancy should, as a rule, have natural lighting - illumination of the premises with sky light (direct or reflected). Natural lighting is divided into side, top and combined (top and side).

ЎNatural lighting of premises depends on:

• 1. Light climate - a set of natural lighting conditions in a particular area, which consist of general climatic conditions, the degree of transparency of the atmosphere, as well as reflectivity environment(albedo of the underlying surface).
• 2. Insolation mode - the duration and intensity of room illumination by direct sunlight, depending on geographical latitude location, orientation of buildings to cardinal directions, shading of windows by trees or houses, size of light openings, etc.

Insolation is an important healing, psycho-physiological factor and should be used in all residential and public buildings with permanent occupancy, with the exception of certain premises of public buildings, where insolation is not allowed due to technological and medical requirements. According to SanPiN No. RB, such premises include:

• § operating rooms;
• § hospital intensive care rooms;
• § exhibition halls of museums;
• § chemical laboratories of universities and research institutes;
• § book depositories;
• § archives.

The insolation regime is assessed by the duration of insolation during the day, the percentage of the insolated area of ​​the room and the amount of radiation heat entering the room through the openings. Optimal insolation efficiency is achieved by daily continuous irradiation of premises with direct sunlight for 2.5 - 3 hours. natural lighting insolation

ЎDepending on the orientation of building windows to the cardinal points, three types of insolation regime are distinguished: maximum, moderate, minimum. (Appendix, Table 1).

With a western orientation, a mixed insolation regime is created. In terms of duration it corresponds to a moderate insolation regime, and in terms of air heating - to a maximum insolation regime. Therefore, according to SNiP 2.08.02-89, windows of intensive care wards, children's wards (up to 3 years old), and playrooms in children's departments are not allowed to be oriented to the west.

In mid-latitudes (territory of the Republic of Belarus) for hospital wards, day care rooms for patients, classrooms, group rooms of children's institutions, the best orientation, providing sufficient illumination and insolation of rooms without overheating, is the southern and southeastern (acceptable - SW, E).

The windows of operating rooms, resuscitation rooms, dressing rooms, treatment rooms, delivery rooms, therapeutic and surgical dentistry rooms are oriented to the north, northwest, northeast, which ensures uniform natural illumination of these rooms with diffused light, eliminates overheating of the rooms and the blinding effect of sunlight, and also the appearance of shine from a medical instrument.

Standardization and assessment of natural lighting in premises

Standardization and hygienic assessment of natural lighting of existing and designed buildings and premises is carried out in accordance with SNiP II-4-79 using lighting engineering (instrumental) and geometric (calculation) methods.

The main lighting indicator of natural lighting of premises is the natural illumination coefficient (KEO) - the ratio of natural illumination created at some point on a given plane inside a room by sky light to the simultaneous value of external horizontal illumination created by the light of a completely open sky (excluding direct sunlight), expressed in percent:

KEO = E1/E2 100%,

where E1 is indoor illumination, lux;

E2 - outdoor illumination, lux.

This coefficient is an integral indicator that determines the level of natural light, taking into account all factors influencing the conditions for the distribution of natural light in the room. Measuring illumination on the working surface and below open air produced by a lux meter (Yu116, Yu117), the operating principle of which is based on converting the energy of the light flux into electricity. The receiving part is a selenium photocell having light-absorbing filters with coefficients of 10, 100 and 1000. The photocell of the device is connected to a galvanometer, the scale of which is calibrated in lux.

ЎWhen working with a lux meter, the following requirements must be observed (MU RB 11.11.12-2002):

• · the receiving plate of the photocell must be placed on the working surface in the plane of its location (horizontal, vertical, inclined);
• · random shadows or shadows from people and equipment should not fall on the photocell; If workplace is shaded during operation by the operator himself or by protruding parts of the equipment, then the illumination should be measured under these actual conditions;
• · measuring device should not be located near sources of strong magnetic fields; Installation of the meter on metal surfaces is not allowed.

The natural light factor (according to SNB 2.04.05-98) is normalized for various rooms taking into account their purpose, the nature and accuracy of the visual work performed. In total, 8 categories of visual accuracy are provided (depending on smallest size object of discrimination, mm) and four subcategories in each category (depending on the contrast of the object of observation with the background and the characteristics of the background itself - light, medium, dark). (Appendix, Table 2).

With side one-sided lighting, the minimum value of KEO is standardized at the point of the conventional working surface (at the level of the workplace) at a distance of 1 m from the wall farthest from the light opening. (Appendix, Table 3).

ЎGeometric method for assessing natural light:

• 1) Light coefficient (LC) - the ratio of the glazed area of ​​windows to the floor area of ​​a given room (the numerator and denominator of the fraction are divided by the value of the numerator). The disadvantage of this indicator is that it does not take into account the configuration and placement of windows, and the depth of the room.
• 2) Laying depth (depth) coefficient (CD) - the ratio of the distance from the light-carrying wall to the opposite wall to the distance from the floor to the upper edge of the window. The short circuit should not exceed 2.5, which is ensured by the width of the ceiling (20-30 cm) and the depth of the room (6 m). However, neither SK nor KZ do not take into account the darkening of windows by opposing buildings, so they additionally determine the angle of incidence of light and the angle of the opening.
• 3) The angle of incidence shows at what angle the rays of light fall on a horizontal working surface. The angle of incidence is formed by two lines emanating from the point of assessment of lighting conditions (workplace), one of which is directed towards the window along the horizontal working surface, the other - towards the upper edge of the window. It must be at least 270.
• 4) The angle of the hole gives an idea of ​​the size of the visible part of the sky illuminating the workplace. The opening angle is formed by two lines emanating from the measuring point, one of which is directed to the upper edge of the window, the other to the upper edge of the opposing building. It must be at least 50.

The assessment of the angles of incidence and opening should be carried out in relation to the workstations furthest from the window. (Appendix, Fig. 1).

Natural lighting is used for general lighting of production and utility rooms. It is created by the radiant energy of the sun and has the most beneficial effect on the human body. When using this type of lighting, meteorological conditions and their changes during the day and periods of the year in a given area should be taken into account. This is necessary in order to know how much natural light will enter the room through the building's light openings: windows - with side lighting, skylights on the upper floors of the building - with overhead lighting. With combined natural lighting, side lighting is added to the overhead lighting.

Premises with constant occupancy should have natural light. The dimensions of light openings established by calculation can be changed by +5, -10%.

Sun protection devices in public and residential buildings should be provided in accordance with the chapters of SNiP on the design of these buildings, as well as with the chapters on building heating engineering.

The following types of natural indoor lighting are distinguished:

• lateral one-sided - when the light openings are located in one of the external walls of the room,

Figure 1. Lateral one-way natural lighting

• side - light openings in two opposite external walls of the room,

Figure 2. Lateral natural lighting

• upper - when lanterns and light openings in the covering, as well as light openings in the walls of the height difference of the building,
• combined - light openings provided for side (top and side) and overhead lighting.

The principle of normalizing natural light

The quality of lighting with natural light is characterized by the coefficient of natural light to eo, which is the ratio of illumination on a horizontal surface indoors to the simultaneous horizontal illumination outside,

,

WhereE V- horizontal illumination indoors in lux;

E n- horizontal illumination outside in lux.

With side lighting, the minimum value of the natural illumination coefficient is normalized - k eo min, and with overhead and combined lighting - its average value - k eo sr. The method for calculating the natural light factor is given in Sanitary standards design of industrial enterprises.

In order to create the most favorable conditions labor standards for natural light have been established. In cases where natural light is insufficient, work surfaces should be additionally illuminated with artificial light. Mixed lighting is allowed provided additional lighting of only working surfaces with general natural lighting.

Building codes and regulations (SNiP 23-05-95) set the coefficients of natural illumination of industrial premises depending on the nature of the work and the degree of accuracy.

To maintain the necessary illumination of the premises, the standards provide for mandatory cleaning of windows and skylights from 3 times a year to 4 times a month. In addition, walls and equipment should be systematically cleaned and painted in light colors.

The standards for natural lighting of industrial buildings, reduced to the K.E.O. standardization, are presented in SNiP 23-05-95. To facilitate the regulation of workplace illumination, all visual work is divided into eight categories according to the degree of accuracy.

SNiP 23-05-95 establish the required value of K.E.O. depending on the accuracy of the work, the type of lighting and the geographical location of the production. The territory of Russia is divided into five light belts, for which the values ​​of K.E.O. are determined by the formula:

WhereN– number of the administrative-territorial district group for the provision of natural light;

e n- the value of the natural illumination coefficient, selected according to SNiP 23-05-95, depending on the characteristics of visual work in a given room and the natural lighting system.

m N— light climate coefficient, which is found according to SNiP tables depending on the type of light openings, their orientation along the horizon and the group number of the administrative region.

To determine whether natural illumination in a production room corresponds to the required standards, illumination is measured with overhead and combined lighting at various points in the room, followed by averaging; at the side - at the least illuminated workplaces. At the same time, the external illumination and the calculated K.E.O. are measured. compared with the norm.

Natural Light Design

1. The design of natural lighting in buildings should be based on the study of labor processes performed indoors, as well as on the light-climatic features of the building construction site. In this case, the following parameters must be defined:

• characteristics and category of visual work;
• group of the administrative district in which the construction of the building is proposed;
• the normalized value of KEO, taking into account the nature of visual work and the light-climatic features of the location of the buildings;
• required uniformity of natural light;
• the duration of use of natural light during the day for different months of the year, taking into account the purpose of the room, operating mode and light climate of the area;
• the need to protect the premises from the glare of sunlight.

2. Design of natural lighting of a building should be carried out in the following sequence:

• 1st stage:
  • determination of requirements for natural lighting of premises;
  • choice of lighting systems;
  • selection of types of light openings and light-transmitting materials;
  • choosing means to limit the glare of direct sunlight;
  • taking into account the orientation of the building and light openings on the sides of the horizon;
• 2nd stage:
  • performing a preliminary calculation of the natural lighting of the premises (determining the required area of ​​light openings);
  • clarification of the parameters of light openings and rooms;
• 3rd stage:
  • performing a verification calculation of the natural lighting of the premises;
  • identification of rooms, zones and areas that have insufficient natural lighting according to standards;
  • determination of requirements for additional artificial lighting of rooms, zones and areas with insufficient natural light;
  • determination of requirements for the operation of light openings;
• 4th stage: making the necessary adjustments to the natural lighting design and repeating the verification calculation (if necessary).

3. The natural lighting system of the building (side, top or combined) should be selected taking into account the following factors:

• the purpose and adopted architectural, planning, volumetric and structural design of the building;
• requirements for natural lighting of premises arising from the peculiarities of production technology and visual work;
• climatic and light-climatic features of the construction site;
• efficiency of natural lighting (in terms of energy costs).

4. Overhead and combined natural lighting should be used mainly in one-story public buildings of large area (indoor markets, stadiums, exhibition pavilions, etc.).

5. Lateral natural lighting should be used in multi-story public and residential buildings, one-story residential buildings, as well as in one-story public buildings in which the ratio of the depth of the premises to the height of the upper edge of the light opening above the conventional working surface does not exceed 8.

6. When choosing light openings and light-transmitting materials, you should consider:

• requirements for natural lighting of premises;
• purpose, volumetric-spatial and constructive solution building;
• orientation of the building along the horizon;
• climatic and light climatic features of the construction site;
• the need to protect premises from insolation;
• degree of air pollution.

7. When designing side natural lighting, shading created by opposing buildings should be taken into account.

8. Translucent fillings of light openings in residential and public buildings are selected taking into account the requirements of SNiP 23-02.

9. For side natural lighting of public buildings with increased requirements for constant natural lighting and sun protection (for example, art galleries), light openings should be oriented towards the northern quarter of the horizon (N-NW-N-NE).

10. The selection of devices for protection from the glare of direct sunlight should be made taking into account:

• orientation of light openings on the sides of the horizon;
• the direction of the sun's rays relative to a person in the room who has a fixed line of sight (student at his desk, draftsman at the drawing board, etc.);
• working hours of the day and year, depending on the purpose of the premises;
• differences between the solar time according to which the solar cards, and maternity time adopted on the territory of the Russian Federation.

When choosing means to protect against the glare of direct sunlight, you should be guided by the requirements of building codes and regulations for the design of residential and public buildings (SNiP 31-01, SNiP 2.08.02).

11. During a single-shift work (educational) process and when operating premises mainly in the first half of the day (for example, lecture halls), when the premises are oriented towards the western quarter of the horizon, the use of sunscreen is not necessary.

The source of natural light is the radiant energy of the sun. The natural average outdoor illumination throughout the year fluctuates sharply by month and hour, reaching middle lane our country's maximum is in June and minimum in December. In addition, during the day, illumination first increases - up to 12 hours, then decreases - in the period from 12 to 14 hours and gradually decreases - until 20 hours.

Natural light has both positive and negative sides.

Solar radiation greatly affects the skin, internal organs and tissues and, above all, the central nervous system. Interestingly, this effect is not limited to the time a person is in the sun, but continues after he goes indoors or night falls. Doctors call it reflex.

The effect of sunlight begins with its influence on skin covering. Human skin unprotected by clothing reflects from 20 to 40% of the visible and closest in wavelength invisible infrared rays that fall on it (20% is reflected by the skin of a tanned person, and 40% is reflected by the most untanned, white skin). The absorbed part (60...65%) of radiant energy penetrates the outer skin and affects the deeper layers of the body.

Ultraviolet and some infrared rays are reflected by the skin to a lesser extent and are more strongly absorbed by the horny, rougher layer of the skin.

In people, long time working in the North, in mines, metro or simply in cities in central Russia, those who are mostly indoors during the daytime and travel along the streets by transport develop solar starvation. The fact is that ordinary window glass in buildings transmits physiologically active ultraviolet rays to an insignificant extent, and in cities already little of them reaches the surface of the Earth as a result of air pollution with dust, smoke, and exhaust gases.

During sun starvation, the skin becomes pale, cold, and loses its freshness. It is poorly supplied with nutrients and oxygen. Blood and lymph circulate weaker in it, waste products are poorly removed from it, and poisoning of the body with waste substances begins. In addition, the capillaries become more fragile, and therefore the tendency to hemorrhage increases.

Those who experience solar starvation experience painful, unpleasant metamorphoses that affect both the psyche and physical state. First of all, activity disturbances appear nervous system: memory and sleep deteriorate, excitability increases in some and indifference, lethargy in others. With the deterioration of calcium metabolism (the appearance of difficulties in the absorption of dietary calcium and phosphorus, which continue to be excreted from the body, and consequently, the tissues become depleted of these necessary substances), teeth begin to rapidly deteriorate, and bone fragility increases. Thus, with prolonged solar fasting, mental abilities and performance decrease, fatigue and irritation set in very quickly, mobility decreases, and the ability to fight microbes entering the body deteriorates (immunity decreases). Undoubtedly, a person experiencing sun starvation is more likely to get colds and other infectious diseases, and the disease is protracted. In these cases, fractures, cuts and any wounds heal slowly and poorly. There is a tendency to pustular diseases in those who have not previously suffered from this, and the course of chronic diseases in those who already have them worsens, inflammatory processes are more severe, which is associated with an increase in the permeability of the vascular walls, and the tendency to edema increases.

Given the degree of beneficial effects of natural light on the human body, occupational health requires maximum use of natural light. It is not arranged only where it is contraindicated by the technological conditions of production, for example, when storing photosensitive chemicals and products.

Thus, solar lighting increases labor productivity up to 10%, and the creation of rational artificial lighting - up to 13%, while in a number of industries defects are reduced to 20...25%. Rational lighting provides psychological comfort, helps reduce visual and general fatigue, reduces the risk of occupational injuries.

According to their design, natural lighting is divided into:

Lateral, carried out through window openings, one- or two-sided (Fig. 4.3 A, b);

Upper, when light enters the room through aeration or skylights, openings in the ceilings (Fig. 4.3 V);

Combined, when side lighting is added to the top lighting (Fig. 4.3 G).

Natural lighting systems are ideal option for almost any building and structure. After all, unlike artificial light, natural light has no flicker, provides full light transmission, is comfortable for the eyes and, of course, is completely free.

And in general, a pleasant, warming ray of light always fills the room with a special atmosphere. Therefore, it is not surprising that since ancient times people have been trying to provide maximum natural light in their buildings.

During its development, humanity has come up with many ways to provide its home with sunlight. But all these methods can be divided into three methods.

So:

• The most commonly used is side lighting. In this case, the light streams through the opening in the wall and falls on the person from the side. Where did the name come from?

Side lighting is quite easy to implement and provides high-quality illumination inside the house. At the same time, in wide halls, when the walls opposite the window are located far away, sunlight does not always reach all corners of the room. To do this, increase the height of the window openings, but such an exit is not always possible.

• More interesting for such rooms is overhead lighting.. In this case, the light falls from the openings in the roof and streams onto the person above.

This type of lighting is almost ideal. After all, with proper planning, you can provide illumination to any corner of the house.

But as you understand, it is only possible with a one-story plan. And heat loss from this type of natural lighting is an order of magnitude higher. After all warm air It always goes up, and there are cold windows.

• That is why there is natural combined lighting. It allows you to take the best of the first two types. After all, combined lighting is called lighting in which the light falls on a person from both above and below.

But as you understand, this type of lighting is also possible only in a one-story building or on the upper floors of multi-story buildings. But the cost of such window systems is not an unimportant limiting factor in their use.

Methods for proper planning of natural lighting

But knowing the types of natural lighting, we are not one step closer to solving the question of how to organize proper lighting at home? To answer this, let us look at the main stages of planning step by step.

Standards for natural lighting of buildings

In order to properly plan lighting, we first of all must answer the question, what should it be? The answer to this question is given to us by SNiP 23 – 05 – 95, which sets KEO standards for industrial, residential and public buildings.

• KEO is the natural light coefficient. It is the ratio between the level of natural light at a certain point in the house and the illumination outside the room.
• The optimality of this parameter was calculated by research institutes and summarized in a table, which has become the norm in design. But in order to use this table we need to know our latitude.

• From the lessons of BZD and geography, you must remember that the further south you go, the higher the intensity of the solar flux. Therefore, the entire territory of our country was divided into five light climate zones, each of which has two subspecies.
• Knowing our light climate zone, we can finally determine the KEO we need. For residential buildings it ranges from 0.2 to 0.5. Moreover, the further south you go, the smaller the KEO.
• This is again due to geography. After all, the further south you go, the higher the outdoor illumination. And KEO is the ratio of illumination outside the room and inside it. Accordingly, to create the same level of illumination for houses in the south and north, the latter will have to make more efforts.

• To move on, we need to find out where is this point in the house for which we will determine the level of illumination? The answer to this question is given to us by clauses 5.4 - 5.6 SNiP 23 - 05 -95.
• According to them, with two-way side lighting of residential premises, the normalized point is the center of the room. With one-way side lighting, the normalized point is a plane one meter from the wall opposite the window. In other rooms, the normalized point is the center of the room.

Note! For one-, two- and three-room apartments This calculation is made for one living room. In a four-room apartment, this calculation is made for two rooms.

• For overhead and combined lighting, the normalized point is a plane one meter from the darkest walls. This standard also applies to industrial premises.
• But everything that we have given above is prescribed for use in residential and public buildings. With production, everything is a little more complicated. The fact is that production is different. On some I process meter-long workpieces, while on others I deal with microcircuits.
• Based on this, all types of work were divided into eight classes depending on the level of visual work. Where products smaller than 0.15 mm are processed, they were assigned to the first group, and where accuracy is not particularly needed, they were assigned to the eighth. And for industrial enterprises, KEO is chosen based on the level of visual work.

Selecting window systems for a building

Natural light will enter our building through the windows. Therefore, knowing the standards that we need to comply with, we can move on to choosing windows.

• The very first task is choosing window systems. That is, we must decide what kind of lighting we will have - top, side or combined in each room. To answer this question, you need to take into account the architectural structure of the building, its geographical location, the materials used, the thermal efficiency of the house, and of course the price will play an important role.
• If you opt for overhead lighting, then you can use so-called skylights or skylights. These are special structures that often, in addition to light, also provide ventilation for buildings.
• Light aeration lanterns in most cases have a rectangular shape. This is due to ease of installation. At the same time, the triangular shape is considered the most successful in terms of lighting. But for triangular skylights there are practically no reliable systems for raising windows for ventilation.
• Light aeration lamps are usually installed above industrial buildings with high internal heat generation, or on buildings located in southern latitudes, as in the video. This is due to the large heat losses of such window systems.

	Rectangular aeration lanterns are recommended for use in climate zones II-IV. Moreover, if the installation is carried out in areas south of 55° latitude, then the orientation of the lantern should be south and north. Such lamps should be used in buildings with excess sensible heat above 23 W/m 2, and with a level of visual performance of IV-VII category.
	Trapezoidal aeration lanterns are designed for the first climate zone. They are used for buildings in which class II-IV visual work is performed and with excess sensible heat above 23 W/m2.
	It is recommended to install skylights in climate zones I-IV. In this case, when buildings are located south of 55 0, diffuse or heat-protected glass should be used as light transmitting materials. It is used for buildings with excess sensible heat less than 23 W/m2 and for all classes of visual work. It is important to note that the lights must be evenly spaced across the entire roof area.
	A skylight with a light-conducting shaft can be used for all climatic zones. It is usually used for buildings with air-conditioned air and a small range of temperature differences (for example, it is quite possible to install it yourself in residential buildings), as well as for areas where class II-VI work is performed. They are widely used in buildings with suspended ceilings.

• Rooflights in Lately are becoming increasingly widespread both in production and in housing construction. This is due to the ease of installation of such systems and a fairly comfortable cost. The heat losses of such window systems are not so great, which allows them to be successfully used in northern latitudes.

Note! To eliminate the possibility of injury to a person, all horizontal and inclined surfaces of vertical lighting must have special grids. They are necessary to prevent falling glass fragments.

• If you decide to use natural side-type room lighting, then SNiP II-4-79 recommends giving preference to standard-type window systems. For such systems, all the necessary calculations have already been made and there are even recommendations. You can see these recommendations in the table below.

• For side natural lighting, an important aspect is the shading of window systems from adjacent buildings. This must be taken into account when making calculations.

• For buildings in which the wall opposite the window is located at a considerable distance, multi-tiered window systems are often installed. But it should be remembered that the height of one tier should not exceed 7.2 meters.
• A very important aspect when choosing window systems is their correct orientation to the cardinal points. After all, it’s no secret that windows facing south provide significantly more light. This should be used to the maximum in buildings constructed in northern latitudes. At the same time, for buildings built in southern latitudes, it is recommended to orient windows to the north and west.

• This will not only make it possible to use daylight more efficiently, but also reduce costs. Indeed, for buildings in southern latitudes, special light-blocking devices are installed to limit the glare of the sun, and with the correct orientation of the windows this can be avoided.

Combination of KEO standards and illumination standards

But KEO standards are not designed for every type of building. Sometimes it may happen that, according to KEO standards, the illumination is sufficient, but the workplace illumination standards are not met.

This lack of natural light can be compensated by creating combined lighting, or linked through critical outdoor lighting.

• Critical outdoor illumination is the natural illumination in an open area equal to the standardized value of artificial lighting. This value allows you to bring the KEO in accordance with the requirements for artificial lighting.
• For this, the formula E n =0.01eE cr is used, where E n is the standardized value of illumination, e is the selected KEO standard, and E cr is our critical external illumination.

• But even this method does not always allow achieving the required standards. After all, natural light indicators do not always make it possible to achieve standardized values ​​of workplace illumination. First of all, this applies to buildings located in northern latitudes, where the intensity of the light flux is lower and heat losses do not make it possible to establish a large number of windows

• Especially for finding the golden mean, there is a so-called calculation of reduced costs for natural lighting. It allows you to determine whether it is more profitable for a building to create high-quality natural lighting or to limit it to combined, or perhaps even artificial, lighting.

Conclusion

Rooms without natural light are not nearly as comfortable as buildings with direct sunlight. Therefore, if such a possibility exists, natural light should definitely be created for any buildings and structures.

Of course, the issue of natural lighting is much more voluminous and multifaceted, but we have fully covered the main aspects of natural lighting in buildings, and we really hope that this will help you in choosing the right lighting for your home or business.