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Natural side lighting. Calculation of time for using natural light indoors. Afternoon and evening

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 effect on the skin. 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.

For people who work for a long time in the North, in mines, metro or simply in cities in central Russia, for those who during the daytime for the most part are indoors, and move along the streets by transport, solar starvation develops. 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. She is poorly supplied 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 the physical state. First of all, disturbances in the activity of the nervous system appear: memory and sleep deteriorate, excitability increases in some and indifference and 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, and 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 window openings, but such a solution 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 multi-storey buildings. But here's the cost window systems is an important 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 uncovering 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 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 lanterns there is practically no reliable systems 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. Found wide application 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 constructed 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 the norms KEO illumination sufficient, but 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 at open area equal to the normalized 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 install 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 what is more profitable for the building to create quality lighting natural or limited to combined, and maybe 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 making the right choice lighting for home or business.

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Surface illuminance represents the ratio of the incident luminous flux to the area of the illuminated surface.

In building lighting technology, the sky is considered as a source of natural light for building premises. Since the brightness of individual points in the sky varies significantly and depends on the position of the sun, the degree and nature of cloudiness, the degree of transparency of the atmosphere and other reasons, it is impossible to establish the value of natural illumination in a room in absolute units (lx).

Therefore, to assess the natural light regime of rooms, a relative value is used, which allows taking into account the uneven brightness of the sky - the so-called daylight factor (KEO)

Natural light factor e m at any point in the room M represents the illuminance ratio at that point E to m to simultaneous external illumination horizontal plane E n located on open place and illuminated by diffuse light from the entire sky. KEO is measured in relative units and shows what percentage at a given point in the room is the illumination of the simultaneous horizontal illumination under open air, i.e.:

e m = (E in m / E n) × 100%

The coefficient of natural illumination is a value standardized by sanitary and hygienic requirements for natural lighting of premises.

According to SNiP 23-05-95 "Natural and artificial lighting", natural lighting is divided into

lateral,
top,
combined (top and side)

The main document regulating the requirements for natural lighting in residential and public buildings is SanPiN 2.2.1/2.1.1.1278-03 " Hygienic requirements to natural, artificial and combined lighting of residential and public buildings."

In accordance with SanPiN 2.1.2.1002-00 “Sanitary and epidemiological requirements for residential buildings and premises,” living rooms and kitchens in residential buildings must have direct natural light. According to these requirements of KEO in living rooms and kitchens there should be at least 0.5% in the middle of the room.

According to SNiP 31-01-2003 "Residential multi-apartment buildings" the ratio of the area of light openings to the floor area of residential premises and kitchens should be taken no more than 1:5.5 and no less than 1:8 for upper floors with light openings in the plane of inclined enclosing structures - at least 1:10, taking into account the lighting characteristics of windows and shading by opposing buildings.

In accordance with SNiP 23-05-95, the normalized values of KEO - e N for buildings located in different light-climatic areas should be determined by the formula:

e N = e N × m N Where N- number of natural light supply group according to the table

Light openings	Orientation of light openings to cardinal directions	Light climate coefficient, m
		Administrative district group number
		1	2	3	4	5
in the external walls of buildings	northern	1	0,9	1,1	1,2	0,8
	northeast, northwest	1	0,9	1,1	1,2	0,8
	western, eastern	1	0,9	1,1	1,1	0,8
	southeast, southwest	1	0,9	1	1,1	0,8
	southern	1	0,9	1	1,1	0,8

Illumination in the room is achieved due to direct diffuse light from the sky and reflected diffuse light from the internal surfaces of the room, opposing buildings and the surface of the ground adjacent to the building. Accordingly, KEO at the point of placement M is defined as the sum:

e m = e n + e O + e Z + e π Where e n- KEO created by direct diffuse light from a section of the sky visible from a given point through openings, taking into account light losses during
the passage of light flux through a glazed opening; e o - KEO, created by reflected light from the internal surfaces of the room (ceiling, walls, floor); e Z - KEO, created by reflected light from opposing buildings; eπ - KEO, created by reflected light from the surface of the earth adjacent to the building (soil, asphalt, grass, etc.)

Direct light from the sky has the greatest influence on the KEO value.

Component from direct light the firmament is determined by the formula:

e n = e n 0 × τ 0×q Where e n 0- geometric KEO (sky coefficient); τ 0 - the overall light transmittance of the opening; q- coefficient taking into account the uneven brightness of the sky;

The overall light transmission coefficient of the opening τ 0 with side lighting is determined as the product of two components:

τ 0 = τ 1 × τ 2 Where τ 1- transmittance of uncontaminated glass or other translucent filling (in modern regulatory documentation
- coefficient of directional transmittance of visible light of window glass or double glazing) τ 2- transmittance of a window block without glazing, taking into account the shading created by the sashes.

The values of the coefficients τ 1 can be taken according to

Introduction

Premises with constant occupancy should have natural light.

Natural lighting is the illumination of premises by direct or reflected light penetrating through light openings in external enclosing structures. Natural lighting should be provided, as a rule, in rooms with constant occupancy. Without natural lighting, it is allowed to design certain types of industrial premises in accordance with the Sanitary Standards for the Design of Industrial Enterprises.

Types of natural lighting

Distinguish the following types natural lighting of premises:

· 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

· lateral - 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

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. Using this type of lighting, one should take into account meteorological conditions and their changes during the day and periods of the year in a given area. This is necessary in order to know how much natural light will enter the room through the light openings of the building: 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%.

The unevenness of natural lighting in industrial and public buildings with overhead or overhead and natural side lighting and main rooms for children and adolescents with side lighting should not exceed 3:1.

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

where E in is the 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 - to eo min, and with overhead and combined lighting - its average value - to eo avg. 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 is provided only for working surfaces in general natural light.

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

Natural light standards industrial buildings, reduced to the standardization of K.E.O., are presented in SNiP 05/23/95. To facilitate the regulation of workplace illumination, all visual work is divided into eight ranks 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 production. The territory of Russia is divided into five light belts, for which the values of K.E.O. are determined by the formula:

where N is the group number of the administrative-territorial region according to the provision of natural light;

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.

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 the suitability of natural light in production premises Illumination to the required standards is measured with overhead and combined lighting - at various points in the room, followed by averaging; with side-by-side lighting - in 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 of 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 room from the glare of sunlight.

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

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;

performance preliminary calculation natural lighting of premises (determining the required area of light openings);

clarification of the parameters of light openings and rooms;

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;

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 primarily in one-story public buildings 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 against 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;

the difference between solar time, according to which solar maps are built, and maternity time adopted in the territory Russian Federation.

When choosing products to protect against the glare of direct sunlight, you should be guided by the requirements building codes and rules 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.

State Educational Institution of Higher Professional Education "Surgut State University"

Khanty-Mansiysk Autonomous Okrug - Ugra

Department of Life Safety

Course work

Topic: “Calculation of natural lighting”

Completed by: student 04-42 group 5th year

Faculty of Chemical Technology

Semenova Yulia Olegovna

Teacher:

Candidate of Chemical Sciences, Associate Professor

Andreeva Tatyana Sergeevna

The course work contains: 15 drawings, 9 tables, 2 sources used (including SP 23-102-2003 and SNiP 23-05-95), calculation formulas, calculations, plan and section of the room (sheet 1, sheet 2, format A 3).

Purpose of the work: determining the area of light openings, that is, the number and geometric dimensions of windows that provide the normalized value of KEO.

Object of study: office.

Volume of work: 41 pages.

Result of the work: the selected dimensions of the light opening meet the requirements of the standards for combined lighting of the office.

Introduction 4

Chapter 1. Types of natural lighting 5

Chapter 2. The principle of rationing natural light 6

Chapter 3. Designing natural lighting 9

Chapter 4. Calculation of natural lighting

4.1. Selecting daylight factor values 12

4.2. Preliminary calculation of the area of light openings and KEO with side lighting 13

4.3. Test calculation of KEO with side lighting 16

4.4. Preliminary calculation of the area of light openings and KEO with overhead lighting 19

4.5. Test calculation of KEO with overhead lighting 23

Chapter 5. Calculation of natural lighting in the office 29

Tables 32

Conclusion 39

References 40

Introduction

Premises with constant occupancy should have natural light.

Natural lighting - lighting of premises with direct or reflected light penetrating through light openings in external enclosing structures. Natural lighting should be provided, as a rule, in rooms with constant occupancy. Without natural lighting, it is allowed to design certain types of industrial premises in accordance with the Sanitary Standards for the Design of Industrial Enterprises.

Types of natural lighting

The following types of natural indoor lighting are distinguished:

side 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 top lighting.

The principle of normalizing natural light

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%.

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,

where E in is the 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 - to eo min, and with overhead and combined lighting - its average value - to eo avg. The method for calculating the natural light factor is given in the Sanitary Standards for the Design of Industrial Enterprises.

In order to create the most favorable working conditions, natural light standards 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.

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:

where N is the group number of the administrative-territorial district according to the provision of natural light;

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.

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 room from the glare of sunlight.

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

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;

performing a preliminary calculation of the natural lighting of the premises (determining the required area of light openings);