duration of natural light. Calculation of the time of use of natural light in the premises

SEI HPE "Surgut State University"

Khanty-Mansiysk Autonomous Okrug - Yugra

Department of Life Safety

Course work

Topic: "Calculation of natural lighting"

Completed by: student 04-42 group 5 course

Faculty of Chemistry and Technology

SemenovaYuliyaOlegovna

Teacher:

PhD, Associate Professor

Andreeva Tatyana Sergeevna

Coursework contains: 15 figures, 9 tables, 2 used sources (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).

The purpose of the work: to determine the area of light openings, that is, the number and geometric dimensions of windows that provide the normalized value of the KEO.

Object of study: office.

Scope of work: 41 pages.

The 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

4.1. Choice of daylight factor values 12

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

4.3. Check 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. Checking 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 permanent residence of people should have natural lighting.

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

Types of natural lighting

There are the following types of natural lighting of premises:

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

Figure 1 - Lateral one-sided natural lighting

lateral - light openings in two opposite outer walls of the room,

Figure 2 - Lateral daylight

upper - when the lanterns and light openings in the coating, as well as light openings in the walls of the building height difference,

· combined - the light openings provided for lateral (top and side) and top illumination.

The principle of rationing 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 favorable 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 arranged light openings of the building: windows - with side lighting, skylights of the upper floors of the building - with overhead lighting. With combined natural lighting, side lighting is added to the top lighting.

Premises with permanent residence of people should have natural lighting. The dimensions of the light openings established by calculation can be changed by +5, -10%.

The unevenness of natural lighting in the premises of industrial and public buildings with overhead or overhead and natural side lighting and the 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 heat engineering.

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

where E in - horizontal illumination indoors in lux;

E n - horizontal illumination outside in lux.

With side lighting, the minimum value of the coefficient of natural illumination is normalized - to eo min, and for overhead and combined lighting - its average value - to eo cf. The method for calculating the coefficient of natural illumination is given in the Sanitary Design Standards for Industrial Enterprises.

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

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

To maintain the necessary illumination of the premises, the norms provide for the 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.

Standards for natural lighting of industrial buildings, reduced to the rationing of K.E.O., are presented in SNiP 23-05-95. To facilitate the rationing of the illumination of workplaces, all visual works are 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 zones, for which the K.E.O. are determined by the formula:

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

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

The coefficient of light climate, which is found according to the tables of SNiP, depending on the type of light openings, their orientation along the sides of the horizon and the group number of the administrative area.

To determine the compliance of natural illumination in the production room with the required standards, the 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 K.E.O. determined by calculation are measured. compared with the norm.

Natural Lighting Design

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

characteristics and category of visual works;

a group of the administrative district in which the construction of the building is supposed;

normalized value of KEO, taking into account the nature of visual works and light and climatic features of the location of buildings;

the required uniformity of natural light;

the duration of the use of natural lighting during the day for different months of the year, taking into account the purpose of the premises, the mode of operation and the light climate of the area;

the need to protect the premises from the blinding action of sunlight.

2. The design of natural lighting of the building should be carried out in the following sequence:

determination of requirements for natural lighting of premises;

choice of lighting systems;

choice of types of light openings and light-transmitting materials;

the choice of means to limit the blinding effect 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);

clarification of the parameters of light openings and rooms;

performing a test calculation of natural lighting of premises;

determination of premises, zones and areas with insufficient natural lighting according to the norms;

determination of requirements for additional artificial lighting of premises, zones and areas with insufficient natural light;

determination of requirements for the operation of light openings;

making the necessary adjustments to the natural lighting project and re-checking the calculation (if necessary).

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

purpose and adopted architectural and planning, volumetric and spatial and constructive solution 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 a large area (covered 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 conditional working surface does not exceed 8.

6. When choosing light openings and light-transmitting materials, the following should be taken into account:

requirements for natural lighting of premises;

purpose, volume-spatial and constructive solution of the building;

orientation of the building on the sides of the horizon;

climatic and light-climatic features of the construction site;

the need to protect the premises from insolation;

degree of air pollution.

7. Consideration should be given to the shading created by opposing buildings when designing side daylight.

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

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

10. The choice of devices for protection against glare from 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 a room with a fixed line of sight (a student at a desk, a draftsman at a 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 on the territory of the Russian Federation.

When choosing means to protect against glare from direct sunlight, one 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 one-shift working (educational) process and during the operation of premises mainly in the first half of the day (for example, lecture halls), when the premises are oriented to the western quarter of the horizon, the use of sunscreen is not necessary.

Calculation of natural light

The purpose of calculating natural lighting is to determine the area of light openings, that is, the number and geometric dimensions of windows that provide a normalized value of KEO.

Selecting KEO values

1. In accordance with SNiP 23-05, the territory of the Russian Federation is zoned into five groups of administrative districts according to light climate resources. The list of administrative districts included in the natural light supply groups is given in Table 1.

2. KEO values in residential and public buildings located in the first group of administrative districts are taken in accordance with SNiP 23-05.

3. KEO values in residential and public buildings located in the second, third, fourth and fifth groups of administrative districts are determined by the formula

e N = e n m N , (1)

where N- number of the group of administrative districts according to table 1;

e n- normalized value of KEO according to Appendix I of SNiP 23-05;

m N- coefficient of light climate, taken according to table 2.

The values obtained by formula (1) should be rounded to tenths.

4. The dimensions and location of the light openings in the room, as well as compliance with the requirements of the norms for natural lighting of the premises, are determined by preliminary and verification calculations.

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

1. Preliminary calculation of the dimensions of light openings with side lighting without taking into account opposing buildings should be carried out using the graphs shown for the premises of residential buildings in Figure 3, for the premises of public buildings - in Figure 4, for school classes - in Figure 5. The calculation should be made in following sequence:

Picture 3 - Graph for determining the relative area of light openings A s.o. /A p with side lighting of residential premises

Picture 4 - Graph for determining the relative area of light openings A s.o. /A p for side lighting of public buildings

Picture 5 - Graph for determining the relative area of light openings A s.o. /A p with side lighting of school classrooms

a) depending on the category of visual work or the purpose of the premises and the group of administrative districts according to the resources of the light climate of the Russian Federation according to SNiP 23-05, determine the normalized value of KEO for the premises in question;

d P h 01 and attitude d P /h 01 ;

c) on the x-axis of the graph (Figures 3, 4 or 5) determine the point corresponding to a certain value d P /h 01 a vertical line is drawn through the found point until it intersects with the curve corresponding to the normalized value of KEO. The ordinate of the intersection point determines the value A s.o. /A p ;

d) dividing the found value A s.o. /A p by 100 and multiplying by the floor area, find the area of light openings in m 2.

2. In the case when the size and location of light openings in the design of buildings were chosen for architectural and construction reasons, a preliminary calculation of the KEO values in the premises should be made according to Figures 3-5 in the following sequence:

a) according to the construction drawings, find the total area of light openings (in the light) A s.o. and illuminated floor area of the room A p and define the relation A s.o. /A p ;

b) determine the depth of the room d P, the height of the upper face of the light openings above the level of the conditional working surface h 01 and attitude d P /h 01 ;

c) taking into account the type of premises, select the appropriate schedule (Figures 3, 4 or 5);

d) by values A s.o. /A p And d P /h 01 on the chart find a point with the corresponding KEO value.

The graphs (Figures 3-5) are developed in relation to the most common in the practice of designing overall schemes of premises and a typical solution of translucent structures - wooden paired opening bindings.

Check calculation of KEO with side lighting

1. Check calculation of KEO Calculation of KEO should be carried out in the following sequence:

a) graph I (Figure 6) is superimposed on the cross section of the room so that its pole (center) 0 is aligned with the calculated point BUT(Figure 8), and the bottom line of the graph - with a trace of the working surface;

b) according to schedule I, the number of rays passing through the cross section of the light opening from the sky is counted n 1 and from the opposing building to the calculated point BUT ;

c) mark the numbers of semicircles on graph I, coinciding with the middle FROM 1 section of the light opening through which the sky is visible from the calculated point, and with the middle FROM 2 sections of the light opening through which the opposing building is visible from the calculated point (Figure 8);

d) schedule II (Figure 7) is superimposed on the plan of the room in such a way that its vertical axis and horizontal, the number of which corresponds to the number of the concentric semicircle (point "c"), pass through the point FROM 1 (Figure 8);

e) count the number of rays P 2 according to schedule II, passing from the sky through the light aperture on the room plan to the design point BUT ;

f) determine the value of the geometric KEO, taking into account direct light from the sky;

g) schedule II is imposed on the plan of the room in such a way that its vertical axis and the horizontal, the number of which corresponds to the number of the concentric semicircle (point "c"), pass through the point FROM 2 ;

h) count the number of rays according to schedule II, passing from the opposing building through the light opening on the floor plan to the calculated point BUT ;

i) determine the value of the geometric coefficient of natural illumination, taking into account the light reflected from the opposing building;

j) determine the value of the angle at which the middle of the sky section is visible from the calculated point on the cross section of the room (Figure 9);

k) by the value of the angle and the given parameters of the room and the surrounding buildings, the values of the coefficients are determined qi , b f , k ZD , r about, And K h, and calculate the value of KEO at the design point of the room.

Picture 6- Chart I for calculating geometric QEO

Picture 7 - Graph II for calculating geometric KEO

Notes

1 Graphs I and II only apply to rectangular skylights.

2 The plan and section of the room are performed (drawn) on the same scale.

BUT- settlement point; 0 - graph pole I; FROM 1 - the middle of the section of the light opening, through which the sky is visible from the calculated point; FROM 2 - the middle of the section of the light opening, through which the opposing building is visible from the calculated point

Picture 8 - An example of using graph I to count the number of rays from the sky and the opposing building

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

1. For a preliminary calculation of the area of light openings for overhead lighting, the following graphs should be used: for rooflights with an opening depth (light shaft) of up to 0.7 m - according to Figure 9; for mine lanterns - according to figures 10, 11; for lanterns of rectangular, trapezoidal, shed with vertical glazing and shed with inclined glazing - according to Figure 12.

Table 1

Fill type	Coefficient values K 1 for graphs in figures
Fill type	1	2, 3
One layer of window glass in steel single blind bindings	-	1,26
The same, in opening bindings	-	1,05
One layer of window glass in wooden single opening bindings	1,13	1,05
Three layers of window glass in separate-paired metal opening covers	-	0,82
The same, in wooden bindings	0,63	0,59
Two layers of window glass in steel double opening sashes	-	0,75
The same, in blind bindings	-	-
Double-glazed windows (two layers of glazing) in steel single opening bindings*	-	1,00
The same, in blind bindings *	-	1,15
Double-glazed windows (three layers of glazing) in steel deaf paired bindings*	-	1,00
Hollow glass blocks	-	0,70
* When using other types of bindings (PVC, wooden, etc.), the coefficient K 1 is taken according to table 3 until the relevant tests are carried out.

The area of light openings of lanterns A s.f determined according to the graphs in Figures 9-12 in the following sequence:

a) depending on the category of visual work or the purpose of the premises and the group of administrative districts according to the light climate resources of the Russian Federation according to SNiP 23-05;

b) on the ordinate of the graph, a point is determined corresponding to the normalized value of KEO, a horizontal line is drawn through the found point until it intersects with the corresponding curve of the graph (Figures 9-12), the value is determined from the abscissa of the intersection point A s.f /A p ;

c) dividing the value A s.f /A p by 100 and multiplying by the floor area, find the area of the light openings of the lanterns in m 2.

Preliminary calculation of KEO values in the premises should be carried out using the graphs in Figures 9-12 in the following sequence:

a) according to the construction drawings, find the total area of the light openings of the lanterns A s.f, illuminated floor area of the room A p and define the relation A s.f /A p ;

b) taking into account the type of lantern, select the appropriate pattern (8, 10, 11 or 12);

c) in the selected figure through a point with an abscissa A s.f /A p draw a vertical line to the intersection with the corresponding graph; the ordinate of the intersection point will be equal to the calculated average value of the daylight factor e cf .

Picture 9 - Graph for determining the average value of KEO e cf in rooms with skylights with an opening depth of up to 0.7 m and plan dimensions, m:

1 - 2.9x5.9; 2 3 - 1.5x1.7

Picture 10 - Graph for determining the average value of KEO e cf in public premises with shaft lanterns with a light shaft depth of 3.50 m and plan dimensions, m:

1 - 2.9x5.9; 2 - 2.7x2.7; 2.9x2.9; 1.5x5.9; 3 - 1.5x1.7

Picture 11 - Graph to determine the average value of KEO e cf in public premises with shaft lamps of diffuse light with a light shaft depth of 3.50 m and plan dimensions, m:

1 - 2.9x5.9; 2 - 2.7x 2.7; 2.9x2.9; 1.5x5.9; 3 - 1.5x1.7

1 - trapezoidal lantern; 2 - shed with inclined glazing;

3 - rectangular lantern; 4 - shed with vertical glazing

Picture 12- Graph for determining the average value of KEO e cp in public places with lanterns

Checking calculation of KEO under overhead lighting

The calculation of KEO is carried out in the following sequence:

a) graph I (Figure 6) is superimposed on the cross section of the room in such a way that the pole (center) 0 of the graph is aligned with the calculated point, and the lower line of the graph is with the trace of the working surface. The number of radially directed beams of graph I passing through the cross section of the first opening is counted ( n 1) 1 , second opening - ( n 1) 2, the third opening - ( n 1) 3, etc.; while marking the numbers of semicircles that pass through the middle of the first, second, third openings, etc.;

b) determine the angles , , etc. between the bottom line of graph I and the line connecting the pole (center) of graph I with the middle of the first, second, third openings, etc .;

c) schedule II (Figure 7) is superimposed on a longitudinal section of the room; at the same time, the graph is positioned so that its vertical axis and the horizontal, the number of which must correspond to the number of the semicircle on graph I, pass through the middle of the opening (point C).

The number of beams is counted according to schedule II, passing through the longitudinal section of the first opening ( n 2) 1 , second opening - ( P 2) 2, the third opening - ( n 2) 3, etc.;

d) calculate the value of the geometric KEO, at the first point of the characteristic section of the room according to the formula

where R- number of light openings;

q- a coefficient that takes into account the uneven brightness of a portion of the sky, visible from the first point, respectively, at angles ,, etc.;

e) repeat the calculations in accordance with paragraphs "a", "b", "c", "d" for all points of the characteristic section of the room up to N inclusive (where N- the number of points at which the calculation of KEO is carried out);

f) determine the average value of the geometric KEO;

g) according to the given parameters of the room and light openings, the values are determined r 2 , k f , ;

The verification calculation of the KEO values at the points of the characteristic section of the room with overhead lighting from rooflights and shaft lights should be performed according to the formula:

where A f.v- area of the upper inlet of the lantern;

N f- number of lights;

q() - coefficient that takes into account the uneven brightness of the CCM cloudy sky;

The angle between the straight line connecting the calculated point with the center of the lower hole of the lantern, and the normal to this hole;

Mean value of the geometric KEO;

K from- light transmission coefficient of the lantern, determined for lanterns with diffuse reflection of the walls, and for lanterns with directional reflection of the walls - by the value of the index of the light opening of the mine lantern i f ;

Picture 13 - Graph to determine the coefficient q() depending on the angle

Picture 14 K from lanterns with diffuse reflection of the shaft walls

Picture 15 - Graph for determining the light transmission coefficient Kc lanterns with directional reflection of the walls of the shaft at different values of the coefficient of diffuse reflection of the walls of the shaft

K h- calculation coefficient taking into account the decrease in EC and illumination during operation due to contamination and aging of translucent fillings in the light openings, as well as a decrease in the reflective properties of the surfaces of the room (factor of safety).

Light opening index of a lantern with holes in the shape of a rectangle i f determined by the formula

where A f.n.- the area of the lower opening of the lantern, m 2;

A f.v- area of the upper opening of the lantern, m 2;

h s.f- height of the light guide shaft of the lantern, m.

R f.v , R f.n- the perimeter of the upper and lower openings of the lantern, respectively, m.

The same, with holes in the shape of a circle - according to the formula

i f = (r f.v + r f.n.) / 2h s.f , (5)

where r f.v , r f.n.- the radius of the upper and lower holes of the lantern, respectively.

Calculate the value of the geometric KEO at the first point of the characteristic section of the room according to the formula

Repeat calculations for all points of the characteristic section of the room until Nj inclusive (where N j- the number of points at which the calculation of KEO is performed).

Determined by the formula

Sequentially, for all points, the direct component of the KEO is calculated by the formula

The reflected component of KEO is determined, the value of which is the same for all points, according to the formula

. (9)

Calculation of natural lighting in the office

Theoretical part

Lighting of workrooms, offices should be designed based on the following requirements:

a) creating the necessary lighting conditions on desktops located in the back of the room when performing a variety of visual work (reading typographical and typewritten texts, handwritten materials, distinguishing details of graphic materials, etc.);

b) providing visual communication with the outer space;

c) protection of premises from blinding and thermal effects of insolation;

d) favorable distribution of brightness in the field of view.

Lateral lighting of workrooms should be carried out, as a rule, by separate light openings (one window for each office). In order to reduce the required area of light openings, the height of the window sill above the floor level is recommended to be taken at least 0.9 m.

When the building is located in the administrative districts of the Russian Federation, groups according to light climate resources, the normalized value of KEO should be taken: with a depth of study rooms (offices) of 5 m or more - according to table 3 in relation to a combined lighting system; less than 5 m - according to table 4 in relation to the natural lighting system.

To ensure visual contact with the outside space, the filling of light openings should, as a rule, be carried out with translucent window glass.

To limit the blinding effect of solar radiation in workrooms and offices, it is necessary to provide curtains and light adjustable blinds. When designing management buildings and buildings for offices for III and IV climatic regions of the Russian Federation, provision should be made for equipping light openings oriented to the horizon sector within 200°-290° with sun protection devices.

In rooms, the values of the reflection coefficient of surfaces should be at least:

ceiling and top of walls.. 0.70

the bottom of the walls .................... 0.50

gender .................................. 0.30.

Practical part

It is required to determine the required window area in the offices of the control building located in the city of Surgut (sheet 1).

Initial data. Room depth d P= 5.5 m, height h= 3.0 m, width b P= 3.0 m, floor area A p\u003d 16.5 m 2, the height of the upper face of the light opening above the conditional working surface h 01 = 1.9 Filling of skylights with transparent glazing on metal single bindings; the thickness of the outer walls is 0.35 m. There is no shading by the opposing buildings.

Solution

1. Given that the depth of the room d P over 5 m, according to table 3 we find that the normalized value of KEO is 0.5%.

2. We make a preliminary calculation of natural light according to the initial depth of the room d P= 5.5 m and the height of the upper edge of the light opening above the conditional working surface h 01 = 1.9 m; determine that d P /h 01 = 5,5/1,9=2,9.

3. Figure 4 on the corresponding curve e= 0.5% find a point with an abscissa d P /h 01 = 2.9. By the ordinate of this point, we determine that the required relative area of the light opening A about / A P = 16,6%.

4. Determine the area of the light opening Oh oh according to the formula:

0,166 A p\u003d 0.166 16.5 \u003d 2.7 m 2.

Therefore, the width of the light opening b o= 2.7 / 1.8 = 1.5 m.

We accept a window block measuring 1.5 x 1.8 m.

5. We make a check calculation of KEO at the point BUT(sheet 1) according to the formula:

6. Overlay graph I for calculating the KEO by the method of A.M. Danilyuk on the cross section of the room (sheet 2), combining the graph pole I - 0 with the point BUT, and the bottom line - with a conditional working surface; count the number of rays according to graph I, passing through the cross section of the light opening: n 1 = 2.

7. We note that through the point FROM on the section of the room (sheet 2) there is a concentric semicircle 26 of graph I.

8. We superimpose schedule II for calculating KEO on the floor plan (sheet 1) in such a way that its vertical axis and horizontal 26 pass through the point FROM; we calculate according to graph II the number of rays passing from the sky through the light aperture: P 2 = 16.

9. Determine the value of the geometric KEO by the formula:

10. On the cross section of the room on a scale of 1:50 (sheet 2), we determine that the middle of the sky area visible from the calculated point A through the light opening is at an angle; according to the value of this angle in table 5 we find the coefficient that takes into account the uneven brightness of the CCM cloudy sky: qi =0,64.

11. According to the size of the room and the light opening, they find that d P /h 01 = 2,9;

l T /d P = 0,82; b P /d P = 0,55.

12. Weighted average reflectance .

13. By found values d P /h 01 ; l T /d P ; b P /d P according to table 6 we find that r o = 4,25.

14. For transparent glazing with metal single binding, we find the total light transmittance.

15 According to SNiP 23-05, we find that the safety factor for windows of public buildings K h = 1,2.

16 We determine the geometric KEO at point A, substituting the values of all found coefficients into the formula:

Consequently, the selected dimensions of the light opening provide the requirements of the standards for combined lighting of the office.

Table 1

Groups of administrative regions

	Administrative region
1	Moscow, Smolensk, Vladimir, Kaluga, Tula, Ryazan, Nizhny Novgorod, Sverdlovsk, Perm, Chelyabinsk, Kurgan, Novosibirsk, Kemerovo regions, the Republic of Mordovia, the Chuvash Republic, the Udmurt Republic, the Republic of Bashkortostan, the Republic of Tatarstan, the Krasnoyarsk Territory (north of 63 ° N. sh.). The Republic of Sakha (Yakutia) (to the north of 63° N), Chukotka Autonom. District, Khabarovsk Territory (north of 55° N)
2	Bryansk, Kursk, Orel, Belgorod, Voronezh, Lipetsk, Tambov, Penza, Samara, Ulyanovsk, Orenburg, Saratov, Volgograd regions, Komi Republic, Kabardino-Balkarian Republic, Republic of North Ossetia-Alania, Chechen Republic, Republic of Ingushetia, Khanty-Mansiysk Autonomous Okrug, Republic of Altai, Krasnoyarsk Territory (south of 63°N), Republic of Sakha (Yakutia) (south of 63°N), Republic of Tyva, Republic of Buryatia, Chita Region, Khabarovsk Territory (south of 55°N) sh.), Magadan, Sakhalin regions
3	Kaliningrad, Pskov, Novgorod, Tver, Yaroslavl, Ivanovo, Leningrad, Vologda, Kostroma, Kirov regions, Republic of Karelia, Yamalo-Nenets Autonomous Okrug, Nenets Autonomous Okrug
4	Arkhangelsk, Murmansk regions
5	Republic of Kalmykia, Rostov, Astrakhan regions, Stavropol Territory, Krasnodar Territory, Republic of Dagestan, Amur Region, Primorsky Territory

table 2

Light climate coefficient

Light openings	Orientation of light openings on the sides of the horizon	Light climate coefficient m N
		Number of the group of administrative regions
		1	2	3	4	5
In the outer walls of the building	FROM	1	0,9	1,1	1,2	0,8
	NE, NW	1	0,9	1,1	1,2	0,8
	Z, V	1	0,9	1,1	1,1	0,8
	SE, SW	1	0,85	1	1,1	0,8
	YU	1	0,85	1	1,1	0,75
In skylights	-	1	0,9	1,2	1,2	0,75
Note - C - northern; NE - northeast; NW - northwestern; B - eastern; Z - western; Yu - southern; SE - southeast; SW - southwest orientation.

Table 3

Normalized KEO values for lateral combined lighting in the main premises of residential and public buildings in administrative districts of various groups according to light climate resources

Groups of administrative regions by light climate resources		KEO, %
Groups of administrative regions by light climate resources			in school classes	in showrooms	in the reading rooms	in the design rooms
1		0,60	1,30	0,40	0,70
		0,60	1,30	0,40	0,70
	159-203	0,60	1,30	0,40	0,70
	294-68	0,60	-	0,40	0,70
2		0,50	1,20	0,40	0,60
		0,50	1,10	0,40	0,60
	159-203	0,50	1,10	0,40	0,60
	294-68	0,50	-	0,40	0,60
3		0,70	1,40	0,50	0,80
		0,60	1,30	0,40	0,70
	159-203	0,60	1,30	0,40	0,70
	294-68	0,70	-	0,50	0,90
4		0,70	1,40	0,50	0,80
		0,70	1,40	0,50	0,80
	159-203	0,70	1,40	0,50	0,80
	294-68	0,70	-	0,50	0,80
5		0,50	1,00	0,30	0,60
		0,50	1,00	0,30	0,60
	159-203	0,50	1,00	0,30	0,50
	294-68	0,50	-	0,30	0,60

Table 4

Normalized KEO values for lateral natural lighting in the main premises of residential and public buildings in various groups of administrative districts according to light climate resources

Admin groups rational areas according to light climate resources	Orientation of light openings on the sides of the horizon, deg.	Normalized values of KEO, %
		in working rooms of management buildings, offices	in school classes	in living quarters	halls	in the reading rooms	in design rooms, drawing and design trade bureaus
1		1,00	1,50	0,50	0,70	1,20	1,50
		1,00	1,50	0,50	0,70	1,20	1,50
	159-203	1,00	1,50	0,50	0,70	1,20	1,50
	294-68	1,00	-	0,50	0,70	1,20	1,50
2		0,90	1,40	0,50	0,60	1,10	1,40
		0,90	1,30	0,40	0,60	1,10	1,30
	159-203	0,90	1,30	0,40	0,60	1,10	1,30
	294-68	0,90	-	0,50	0,60	1,10	1,40
3		1,10	1,70	0,60	0,80	1,30	1,70
		1,00	1,50	0,50	0,70	1,20	1,50
	159-203	1,00	1,50	0,50	0,70	1,20	1,50
	294-68	1,10	-	0,60	0,80	1,30	1,70
4		1,10	1,70	0,60	0,80	1,30	1,70
		1,10	1,70	0,60	0,80	1,30	1,70
	159-203	1,10	1,70	0,60	0,80	1,30	1,70
	294-68	1,20	-	0,60	0,80	1,40	1,80
5		0,80	1,20	0,40	0,60	1,00	1,20
		0,80	1,20	0,40	0,60	1,00	1,20
	159-203	0,80	1,10	0,40	0,50	0,90	1,10
	294-68	0,80	-	0,40	0,60	0,90	1,20

Table 5

Coefficient values qi

The angular height of the middle ray of the sky section, visible from the calculated point through the light opening in the section of the room, deg.	Coefficient values qi
2	0,46
6	0,52
10	0,58
14	0,64
18	0,69
22	0,75
26	0,80
30	0,86
34	0,91
38	0,96
42	1,00
46	1,04
50	1,08
54	1,12
58	1,16
62	1,18
66	1,21
70	1,23
74	1,25
78	1,27
82	1,28
86	1,28
90	1,29
Notes 1 For values of the angular heights of the middle beam, different from those given in the table, the values of the coefficient qi determined by interpolation. 2 In practical calculations, the angular height of the middle beam of the sky section, visible from the calculated point through the light opening in the section of the room, should be replaced by the angular height of the middle of the sky section, visible from the calculated point through the light opening.

Table 6

Values r o for a conditional work surface

Room depth ratio d P to the height from the level of the conditional work surface to the top of the window h 01	The ratio of the distance of the calculated point from the inner surface of the outer wall l T to the depth of the room d P	Weighted average reflectance of floor, walls and ceiling
		0,60			0,50			0,45			0,35
		Room length ratio a p to its depth d P
		0,5	1,0	2,0	0,5	1,0	2,0	0,5	1,0	2,0	0,5	1,0	2,0
1,00	0,10	1,03	1,03	1,02	1,02	1,02	1,02	1,02	1,02	1,01	1,01	1,01	1,01
1,00	0,50	1,66	1,59	1,46	1,47	1,42	1,33	1,37	1,34	1,26	1,19	1,17	1,13
1,00	0,90	2,86	2,67	2,30	2,33	2,19	1,93	2,06	1,95	1,74	1,53	1,48	1,37
3,00	0,10	1,10	1,09	1,07	1,07	1,06	1,05	1,06	1,05	1,04	1,03	1,03	1,02
3,00	0,20	1,32	1,29	1,22	1,23	1,20	1,16	1,18	1,16	1,13	1,09	1,08	1,06
3,00	0,30	1,72	1,64	1,50	1,51	1,46	1,36	1,41	1,37	1,29	1,20	1,18	1,14
3,00	0,40	2,28	2,15	1,90	1,91	1,82	1,64	1,73	1,66	1,51	1,37	1,33	1,26
3,00	0,50	2,97	2,77	2,38	2,40	2,26	1,98	2,12	2,01	1,79	1,56	1,51	1,39
3,00	0,60	3,75	3,47	2,92	2,96	2,76	2,37	2,57	2,41	2,10	1,78	1,71	1,55
3,00	0,70	4,61	4,25	3,52	3,58	3,32	2,80	3,06	2,86	2,44	2,03	1,93	1,72
3,00	0,80	5,55	5,09	4,18	4,25	3,92	3,27	3,60	3,34	2,82	2,30	2,17	1,91
3,00	0,90	6,57	6,01	4,90	4,98	4,58	3,78	4,18	3,86	3,23	2,59	2,43	2,11
5,00	0,10	1,16	1,15	1,11	1,12	1,11	1,08	1,09	1,08	1,07	1,05	1,04	1,03
5,00	0,20	1,53	1,48	1,37	1,38	1,34	1,27	1,30	1,27	1,21	1,15	1,14	1,11
5,00	0,30	2,19	2,07	1,84	1,85	1,77	1,60	1,68	1,61	1,48	1,34	1,31	1,24
5,00	0,40	3,13	2,92	2,49	2,52	2,37	2,07	2,22	2,10	1,85	1,61	1,55	1,43
5,00	0,50	4,28	3,95	3,29	3,34	3,11	2,64	2,87	2,68	2,31	1,94	1,84	1,66
5,00	0,60	5,58	5,12	4,20	4,27	3,94	3,29	3,61	3,35	2,83	2,31	2,18	1,92
5,00	0,70	7,01	6,41	5,21	5,29	4,86	4,01	4,44	4,09	3,40	2,72	2,55	2,20
5,00	0,80	8,58	7,82	6,31	6,41	5,87	4,79	5,33	4,90	4,03	3,17	2,95	2,52
5,00	0,90	10,28	9,35	7,49	7,63	6,96	5,64	6,30	5,77	4,71	3,65	3,39	2,86

If the surface finish of the room is unknown, then for the premises of residential and public buildings, the weighted average reflection coefficient should be taken equal to 0.50.

Table 7

Coefficients 1 and

Type of light-transmitting material	Values	Type of binding	Values
Sheet window glass:	Bindings for windows and lanterns of industrial buildings:
single	Bindings for windows and lanterns of industrial buildings:	0,9
double	0,8	wooden:
triple	0,75	single	0,75
Display glass 6-8 mm thick	0,8	paired	0,7
Reinforced sheet glass	0,6	double separate	0,6
Patterned sheet glass	0,65	steel:
Sheet glass with special properties:	single opening	0,75
Sheet glass with special properties:	single voiceless	0,9
sunscreen	0,65	double opening	0,6
contrast	0,75	double deaf	0,8
Organic glass:	Bindings for windows of residential, public and auxiliary buildings:
transparent		0,9
dairy		0,6
Hollow glass blocks:	wooden:
light-scattering	0,5	single	0,8
translucent	0,55	paired	0,75
Double-glazed windows	0,8	double separate	0,65
with triple glazing	0,5
metal:
single	0,9
paired	0,85
double separate	0,8
with triple glazing	0,7
Glass-reinforced concrete panels with hollow glass blocks with a joint thickness of:
20 mm or less	0,9
over 20 mm	0,85

Table 8

The values of the coefficients and

Supporting structures of coatings	Coefficient taking into account light losses in load-bearing structures,	Sun protection devices, products and materials	Factor taking into account light loss in sun protection devices,
steel trusses	0,9	Retractable adjustable blinds and curtains (inter-pane, internal, external)	1,0
Reinforced concrete and wooden trusses and arches	0,8	Stationary blinds and screens with a protective angle of not more than 45° when the blinds or screens are located at an angle of 90° to the plane of the window:
horizontal	0,65
vertical	0,75
Solid beams and frames with section height:	Horizontal visors:
Solid beams and frames with section height:	with a protective angle not more than 30°	0,8
50 cm or more	0,8	with a protective angle from 15° to 45°	0,9-0,6
less than 50 cm	0,9	(multi-stage)
Balconies depth:
up to 1.20 m	0,90
1.50 m	0,85
2.00 m	0,78
3.00 m	0,62
Loggia depth:
up to 1.20 m	0,80
1.50 m	0,70
2.00 m	0,55
3.00 m	0,22

Conclusion

In the course of the course work, I studied such a parameter as natural lighting. The principle of rationing natural lighting, as well as the design of natural lighting, was considered. In this work, I made a calculation of natural lighting in the office. The normalized value of the daylight factor is 0.5% for the selected county. Having done a preliminary calculation, I found out the dimensions of the window block for sufficient illumination: 1.5 * 1.8. In the verification calculation, I confirmed the correctness of the chosen dimensions of the light opening, as they provide the requirements of the standards for combined lighting of the office. The coefficient of natural light in the test calculation is 0.53%.

Natural lighting is the most favorable for vision, since sunlight is necessary for normal human life. Visible rays of the solar spectrum (400-760 microns) provide the function of vision, determine the natural biorhythm of the body, positively affect emotions, the intensity of metabolic processes; ultraviolet spectrum (290-400 microns) - stimulates the processes of metabolism, hematopoiesis, tissue regeneration and has anti-rachitic (vitamin D synthesis) and bactericidal action.

All premises with a permanent stay of people should, as a rule, have natural lighting.

Natural lighting of premises is created by direct, diffused and reflected sunlight. It can be side, top, combined. Lateral lighting - through light openings in the outer walls, upper - through light openings in the coating and lanterns, and combined - in the outer walls and coatings.

The most hygienic side lighting, penetrating through the windows, since the overhead light with the same glazing area creates less illumination of the room; in addition, skylights and lights located in the ceiling are less convenient for cleaning and require special tools for this purpose. It is possible to use secondary lighting, i.e. lighting through glazed partitions from an adjacent room equipped with windows. However, it does not meet hygienic requirements and is allowed only in such premises as corridors, wardrobes, bathrooms, showers, utility rooms, washing departments.

The design of natural lighting for buildings should be based on a detailed study of technological or other processes performed indoors, as well as on the light and climatic features of the territory. This takes into account:

Characteristics of visual work; location of the building on the light climate map;

The required uniformity of natural lighting;

Equipment location;

The desired direction of incidence of the light flux on the work surface;

The duration of the use of natural light during the day;

The need for protection from the glare of direct sunlight.

As hygienic indicators of natural illumination of premises, the following are used:

Coefficient of natural illumination (KEO) - the ratio of natural illumination inside the premises at control measurement points (at least 5) to the illumination outside the building (%). There are two groups of methods for determining KEO - instrumental and calculation.

In rooms with side lighting, the minimum value of the coefficient is normalized, and in rooms with overhead and combined lighting - the average. For example, KEO in sales areas with side lighting should be 0.4-0.5%, with top lighting - 2%.

For public catering enterprises, when designing side natural lighting, KEO should be: for halls, buffets - 0.4-0.5%; hot, cold, confectionery, pre-preparation and procurement shops - 0.8-1%; washing kitchen and tableware - 0.4-0.5%.

Light coefficient - the ratio of the area of the glazed surface of windows to the area of the floor. In industrial, commercial and administrative premises, it should be at least -1:8, in household - 1:10.

However, this coefficient does not take into account climatic conditions, architectural features of the building and other factors affecting the intensity of lighting. So, the intensity of natural lighting largely depends on the arrangement and location of windows, their orientation to the cardinal points, the shading of windows by nearby buildings, green spaces.

Incident angle - the angle formed by two lines, one of which runs from the workplace to the upper edge of the glazed part of the window opening, the other - horizontally from the workplace to the window. The angle of incidence decreases with distance from the window. It is believed that for normal illumination with natural light, the angle of incidence must be at least 27 °. The higher the window, the greater the angle of incidence.

Opening angle - the angle formed by two lines, one of which connects the workplace with the upper edge of the window, the other - with the highest point of the obscuring object located in front of the window (opposing building, tree, etc.). With such dimming, the illumination in the room may turn out to be unsatisfactory, although the angle of incidence and light coefficient are quite sufficient. The hole angle must be at least 5o.

The illumination of the premises is directly dependent on the number, shape and size of windows, as well as on the quality and cleanliness of the glass.

Dirty glass with double glazing reduces natural light to 50-70%, smooth glass retains 6-10% of light, frosted - 60, frozen - up to 80%.

The color of the walls affects the illumination of the premises: white reflects up to 80% of the sun's rays, gray and yellow - 40%, and blue and green - 10-17%.

To make better use of the light flux entering the room, walls, ceilings, and equipment should be painted in light colors. Particularly important is the light coloring of window frames, ceilings, and upper parts of walls, which provide maximum reflected light rays.

Dramatically reduces the natural illumination of the premises by cluttering up the light openings. Therefore, enterprises are prohibited from filling windows with equipment, products, containers both inside and outside the building, as well as replacing glass with plywood, cardboard, etc.

In warehouses, lighting is usually not provided, and in some cases it is undesirable (for example, in pantries for storing vegetables), and is not allowed (in refrigerators). However, for the storage of flour, cereals, pasta, food concentrates, dried fruits, natural lighting is advisable.

In case of insufficient natural light, combined lighting is allowed, in which both natural and artificial light are used.

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 the right lighting at home? To answer it, let's take a step-by-step look at the main stages of planning.

Standards for natural lighting in buildings

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

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

From the lessons of the Belarusian Railways and geography, you must remember that the further south, the higher the intensity of the solar flow. 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, the smaller the KEO.
Again, this has to do with geography. After all, the further south, the higher the illumination outdoors. 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 paragraph 5.4 - 5.6 of SNiP 23 - 05 -95.
According to them, with two-sided side lighting of residential premises, the normalized point is the center of the room. With one-sided side lighting, the normalized point is the 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, such a calculation is made for one living room. In a four-room apartment, such a calculation is made for two rooms.

For overhead and combined lighting, the normalized point is a plane a meter from the darkest walls. This rule also applies to industrial premises.
But all that we have given above, the instruction prescribes to be applied to residential and public buildings. With production, everything is a little more complicated. The thing is, production is different. On some I process meter blanks, while on others I deal with microcircuits.
Based on this, all types of work were divided into eight classes depending on the category of visual work. Where products less 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 category of visual work.

The choice of window systems for the building

Natural light will enter our building through the windows. Therefore, knowing the norms that we need to comply with, we can proceed to the choice of windows.

The first task is the choice of 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, it is necessary 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 the so-called light-aeration or skylights. These are special structures, which often, in addition to light, also provide ventilation for buildings.
Light-aeration lamps in most cases have a rectangular shape. This is due to the ease of installation. At the same time, the triangular shape is considered the most successful in terms of lighting. But for triangular lanterns, there are practically no reliable systems for raising windows for ventilation.
Light-aeration lanterns are usually installed above industrial buildings with a large internal heat release, or on buildings located in southern latitudes, as in the video. This is due to the large heat losses of such window systems.

	Rectangular light-aeration lanterns are recommended for use in II-IV climatic zones. At the same time, if the installation is carried out in the territories south of 55 ° latitude, then the orientation of the lamp should be made to the south and north. Such lanterns should be used in buildings with an excess of sensible heat above 23 W / m 2, and with a level of visual work of the IV-VII category.
	Trapezoidal light-aeration lamps are designed for the first climatic zone. They are used for buildings in which class II-IV visual work is performed and having an excess of sensible heat above 23 W / m 2.
	Antiaircraft lamps are recommended to be installed in I-IV climatic zones. At the same time, when buildings are located south of 55 0, diffusing or heat-protective glasses should be used as light-transmitting materials. It is used for buildings with an excess of sensible heat less than 23 W / m 2 and for all classes of visual work. It is important to note that the lights should be evenly spaced over the entire roof area.
	Anti-aircraft lamp with a light guide shaft can be used for all climatic zones. It is usually used for buildings with air conditioning and a small range of temperature differences (for example, it is quite possible to mount it yourself in residential buildings), as well as for areas where class II-VI work is performed. Found wide application in buildings with false ceilings.

Skylights have recently become more and more 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 the fall of glass fragments.

If you decide to use natural side-type lighting in rooms, 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 lateral natural lighting, an important aspect is the shading of window systems from adjacent buildings. This must be taken into account in the calculations.

For buildings in which the wall opposite the window is at a considerable distance, multi-tiered window systems are often mounted. 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 not a secret for anyone that south-facing windows give much more light. This should be used to the maximum in buildings under construction in northern latitudes. At the same time, for buildings under construction in southern latitudes, it is recommended to orient windows to the north and west.

This will allow not only more rational use of daylight hours, but also reduce costs. Indeed, for buildings in the southern latitudes, special light-blocking devices are mounted 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 calculated for every type of building. Sometimes it may happen that, according to the KEO standards, the illumination is sufficient, but the workplace illumination standards are not met.

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

Critical outdoor illumination is called natural illumination in an open area equal to the normalized value of artificial lighting. This value allows you to bring KEO in accordance with the requirements for artificial lighting.
For this, the formula E n \u003d 0.01eE cr is used, where E n is the normalized value of illumination, e is the selected KEO standard, and E cr is our critical outdoor illumination.

But even this method does not always achieve the required standards. After all, indicators of natural lighting do not always allow achieving the normalized values of illumination of the workplace. First of all, this applies to buildings located in northern latitudes, where both 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 the reduced costs for natural lighting. It allows you to determine what is more profitable for the building to create high-quality natural lighting or limit it to combined, or maybe even artificial lighting.

Output

Rooms without natural light are nowhere near as comfortable as buildings with direct sunlight. Therefore, if possible, natural light must be created for any buildings and structures.

Of course, the issue of natural lighting is much more voluminous and multifaceted, but we have fully disclosed 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.

Premises with a permanent stay of people should, as a rule, have natural lighting - lighting the premises with skylight (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 are made up of general climatic conditions, the degree of transparency of the atmosphere, as well as the reflective abilities of the environment (albedo of the underlying surface).
2. Insolation regime - the duration and intensity of illumination of the room by direct sunlight, depending on the geographical latitude of the place, the orientation of buildings to the cardinal points, the shading of windows by trees or houses, the size of the light openings, etc.

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

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

The insolation regime is estimated 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 openings. The optimal efficiency of insolation is achieved by daily continuous exposure to direct sunlight of the premises for 2.5 - 3 hours. natural lighting insolation

ЎDepending on the orientation of the windows of buildings to the cardinal points, there are three types of insolation regime: 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, in terms of air heating - to the maximum insolation regime. Therefore, according to SNiP 2.08.02-89, the windows of intensive care units, 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 rooms for patients, classes, group rooms of children's institutions, the best orientation that provides sufficient illumination and insolation of the premises without overheating is south and southeast (permissible - SW, E).

The windows of operating rooms, resuscitation rooms, dressing rooms, treatment rooms, delivery rooms, offices of therapeutic and surgical dentistry 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 luster from a medical instrument.

Rationing and assessment of natural lighting of premises

Rationing and hygienic assessment of natural lighting of existing and planned buildings and premises is carried out in accordance with SNiP II-4-79 by lighting (instrumental) and geometric (calculation) methods.

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

KEO \u003d E1 / E2 100%,

where E1 - indoor illumination, lx;

E2 - outdoor illumination, lx.

This coefficient is an integral indicator that determines the level of natural light, taking into account all the factors that affect the conditions for the distribution of natural light in the room. Measurement of illumination on the working surface and in the open air is carried out with a luxmeter (Yu116, YU117), the principle of operation of which is based on the conversion of the energy of the luminous flux into electric current. The receiving part is a selenium photocell with light-absorbing filters with coefficients of 10, 100 and 1000. The device's photocell is connected to a galvanometer, the scale of which is calibrated in lux.

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

· the receiving plate of the photocell should be placed on the working surface in the plane of its location (horizontal, vertical, inclined);
· the photocell must not be subject to accidental shadows or shadows from a person and equipment; if the workplace is shaded during work by the working or protruding parts of the equipment, then the illumination should be measured in these real conditions;
· the measuring device should not be located near sources of strong magnetic fields; installation of the meter on metal surfaces is not allowed.

The coefficient of natural illumination (according to SNB 2.04.05-98) is normalized for various premises, taking into account their purpose, the nature and accuracy of the visual work performed. In total, 8 digits of visual work accuracy are provided (depending on the smallest size of the object of distinction, mm) and four sub-digits in each digit (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 normalized at the point of the conditional 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).

Geometric method for estimating natural light:

1) Light coefficient (SC) - the ratio of the glazed area of windows to the floor area of \u200b\u200bthe given room (the numerator and denominator of the fraction are divided by the numerator value). The disadvantage of this indicator is that it does not take into account the configuration and placement of windows, the depth of the room.
2) Coefficient of laying depth (deepening) (KZ) - the ratio of the distance from the light-bearing wall to the opposite wall to the distance from the floor to the upper edge of the window. KZ should not exceed 2.5, which is ensured by the width of the lintel (20-30 cm) and the depth of the room (6 m). However, neither SC nor SC do not take into account the darkening of windows by opposing buildings, therefore, the angle of incidence of light and the angle of the opening are additionally determined.
3) The angle of incidence indicates at what angle the rays of light fall on a horizontal work 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 to the window along the horizontal working surface, the other - to 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 corner of the opening is formed by two lines emanating from the measurement 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 evaluation of the angles of incidence and opening should be carried out in relation to the workstations furthest from the window. (Appendix, Fig. 1).