Natural illumination coefficient (CEO). Calculation of lateral unilateral natural lighting Duration of natural lighting during

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-firmic features of the construction site of buildings. The following parameters must be defined:

characteristic and discharge of visual works;

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

the normalized value of the CEO, taking into account the nature of the visual works and the light-gravatical features of the location of buildings;

required uniformity of natural lighting;

the duration of the use of natural lighting during the day for various months of the year, taking into account the designation of the room, the mode of operation and the light climate of the area;

the need to protect the room from the blinding of sunlight.

The design of natural lighting of the building should be performed in the following sequence:

determination of requirements for natural lighting of premises;

selection of lighting systems;

selection of types of light opening and light-resistant materials;

the choice of means to limit the blinding effect of direct sunlight;

accounting of the orientation of the building and lighting openings on the sides of the horizon;

performing the preliminary calculation of the natural lighting of the premises (determination of the required area of \u200b\u200blight openings);

refinement of the parameters of light opening and premises;

performing the verification calculation of natural lighting of the premises;

definition of premises, zones and plots that have insufficient natural lighting;

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

determination of requirements for operation of light openings;

making the necessary adjustments to the project of natural lighting and repeated verification calculation (if necessary).

The system of natural lighting of the building (lateral, top or combined) should be selected taking into account the following factors: the appointment and adopted architectural and planning, large-spatial and constructive solution of the building;

requirements for natural lighting of premises arising from the features of production technology and visual work; climatic and light-firmic features of the construction site; The economy of natural lighting (for energy costs).

The upper and combined natural light should be used mainly in single-storey public buildings of a large area (covered markets, stadiums, exhibition pavilions, etc.).

Side natural lighting should be used in multi-storey public and residential buildings, single-storey residential buildings, as well as in one-story public buildings, in which the ratio of the depths of the premises to the height of the upper face of the light opening over the conditional working surface does not exceed 8.

When choosing light opening and light-resistant materials, it should be considered:

requirements for natural lighting of premises; appointment, volume and spatial and constructive solution of the building; Orientation of the building on the sides of the horizon; climatic and light-gravatical features of the construction site;

the need to protect premises from insolation; The degree of air pollution.

When designing lateral natural lighting, the shading created by opposing buildings should be taken into account. Accounting for shading is carried out in accordance with the section of this Code of Rules.

The selection of devices for protection against the blinding effect of direct sunlight should be made according to:

orientation of light openings on the sides of the horizon;

directions of sunlight relative to a person in a room having a fixed line of view (a student at the desk, a drawer behind the drawing board, etc.);

time of day and year, depending on the purpose of the premises;

the differences between sunny time, which built solar cards, and maternity times adopted in the Russian Federation.

When choosing means to protect against the blinding effect of direct sunlight, the requirements of the construction standards and the rules for the design of residential and public buildings should be followed (SNiP 31-01, SNiP 2.08.02).

With a single-handed worker (training) process and during the operation of premises mainly in the first half of the day (for example, lecture audiences), when the premises are focused on the Western quarter of the horizon, the use of sunscreen is optional.

In some cases, for example, during the examination, there is a need for an objective assessment of the natural lighting of premises based on CEO measurements using luxmeters. Modern photometric devices as a sensor have silicon photocells, equipped with yellow and green light filters that corrected their spectral sensitivity of the spectral sensitivity of the human eye, as well as special cosine correction nozzles. Correction of spectral sensitivity and cosine can also be carried out using a computer. Selena cells are applied less often, as they are short-lived, require constant graduation on a photometric bench.

Their sensitivity depends on the air temperature. Considering that all calculations and CEO standards have an ICO cloudy sky as the main assumption, the CEO measurements can only be carried out with a continuous decadeal cloud. However, there may be exceptions, for example, in the case of measuring the CEO in the presence of light guides or light-directional devices. At the same time, the value of the CEO becomes conditional. And when measuring outdoor illumination, it is necessary to shield the straight light of the sun.

In calculating the effectiveness of such devices, the total illumination from the direct sun and the sky should be taken as the external illumination value (EQ).

To measure the CEO, the journal of inventive measurements is harvested, in which the place, time and weather conditions are indicated during measurements, instruments, the proportionality ratio between the readings of the luxmeters (in the case of low-quality instruments), the geometric parameters of the room and light, the reflection coefficients of the internal and adjacent outer surfaces, the view Filling out the opening and its pollution. The reserve coefficient is determined by dividing the readings of the luxmeter when the sensor is positioned in the vertical plane outside the glass and inside the glass. Reflection coefficients of surfaces are measured using a reflexometer. In addition to these data, the log must contain tables to record measurement results. The results of measurements inside the room usually at five points on the working surface, pre-marked by the characteristic cut, are synchronized by time with the results of measurements of the outer illumination, produced on an open outdoor area, preferably on the roof of the building. For this, outdoor illumination is measured every minute. About each result records the measurement time. Internal illumination at the outlined points is measured at the same time. The time of each measurement is also recorded. When filling out the measurement log in the "Outdoor Illumination" column, the result is selected by time with the result of measuring the internal illumination at this point. Measurement at each point to exclude random errors should be carried out at least two times. The results obtained must be averaged.

The percentage is determined by the division of the testimony of the internal luxeter on the reading of the outer luxmeter and is multiplied by 100. If there are a "tariff" coefficient to between the testimony of internal determination by the formula

I like

The surface illumination represents the ratio of the falling light flux to the area of \u200b\u200bthe illuminated surface.

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

Therefore, to assess the natural light mode of the premises, a relative value is used, which allows to take into account the uneven brightness of the sky, - the so-called natural Light Coefficient (CEO)

Natural light coefficient e M. at any point of the room M. Represents the ratio of illumination at this point. E in M. To the simultaneous outer illumination of the horizontal plane E N.located in an open and illuminated by the diffuse light of the whole sky. CEO is measured in relative units and shows what fraction in percentages at this point of the room is illuminated from the simultaneous horizontal illumination in the open air, i.e.:

e M \u003d (E V M / E H) × 100%

The natural light coefficient is the magnitude normalized by sanitary and hygienic requirements for natural lighting of the 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 governing the requirements for natural coverage of the premises of residential and public buildings is SanPine 2.2.1 / 2.1.1.1278-03 "Hygienic requirements for natural, artificial and combined coverage of residential and public buildings."

In accordance with SanPine 2.1.2.1002-00 "Sanitary and epidemiological requirements for residential buildings and premises" in residential buildings Immediate natural lighting should have residential and kitchens. According to these requirements of the CEO, in residential rooms and kitchens should be at least 0.5% in the middle of the room.

According to SNiP 31-01-2003 "Buildings of residential apartment" attitude of the area of \u200b\u200blight openings to the floor area of \u200b\u200bresidential premises and the kitchens should be taken no more than 1: 5.5 and at least 1: 8 for the upper floors with light beats in the plane of inclined enclosing structures - At least 1:10, taking into account the lighting characteristics of windows and shading with opposing buildings.

In accordance with SNiP 23-05-95, normalized values \u200b\u200bof Keo - E N, for buildings disposed in various light-firmicities, should be determined by the formula:

e n \u003d En × m n Where N. - Natural Light Group Number Natural Light

Light Pieces	Orientation of light outlooks on the sides of the world	Light climate coefficient, M
		Administrative Region Number
		1	2	3	4	5
in the outdoor walls of buildings	north	1	0,9	1,1	1,2	0,8
	northeast, North-West	1	0,9	1,1	1,2	0,8
	west, Eastern	1	0,9	1,1	1,1	0,8
	southeast, South-West	1	0,9	1	1,1	0,8
	south	1	0,9	1	1,1	0,8

The illumination in the room is achieved due to the direct diffuse light of the sky and the reflected diffuse light from the inner surfaces of the room, opposing buildings and the surface of the earth adjacent to the building. Accordingly, the CEO at the point of the room m is defined as the sum:

e M \u003d E H + E O + E C + E π Where e N. - CEO, created by the direct diffuse light of the sky section, visible from this point through the purses, taking into account the loss of light when
passing the light flux through the glazed opening; e. O - CEO, created by the reflected light from the inner surfaces of the room (ceiling, walls, floor); e. Z - CEO, created by the reflected light from opposing buildings; e. π - CEO, created by the reflected light from the surface adjacent to the building (soil, asphalt, herbal cover, etc.)

The maximum effect on the size of the Kea has a direct light of the sky.

The straight light of the sky is determined by the formula:

e N \u003d EN 0 × τ 0 × Q. Where eN 0. - geometric KEO (cylinder of the sky); τ 0 - the overall coefficient of light transmission; q. - coefficient taking into account the uneven brightness of the sky;

The total coefficient of light turnout τ 0 with lateral lighting is defined as a product of two components:

τ 0 \u003d τ 1 × τ 2 Where τ 1. - the transmission coefficient of ungadst glass or other translucent filling (in modern regulatory documentation
- The coefficient of directional transmission of visible light of window glass or glass) τ 2. - The transmission coefficient of the window block without glazing when taking into account the shading created by the bindings.

The values \u200b\u200bof the coefficients τ 1 can be accepted by

Premises with a permanent stay of people should have, as a rule, natural lighting - the lighting of the room with the light of the sky (direct or reflected). Natural lighting is divided into lateral, upper and combined (top and side).

Ў Overnamed room lighting depends on:

1. The light climate is a set of natural lighting conditions in one area or another, which are made up of general climatic conditions, the degree of transparency of the atmosphere, as well as the reflective environmental abilities (albedo of the underlying surface).
2. Insolation mode - the duration and intensity of the lighting of the room with direct solar rays, depending on the geographical latitude of the place, orientation of buildings on the sides of the light, shading windows by trees or houses, the magnitude of light guides, etc.

Insolation is an important healing, psycho-physiological factor and should be used in all residential and public buildings with a permanent stay of people, with the exception of individual premises of public buildings, where insolation is not allowed on technological and medical requirements. To such premises according to Sanpin No. RB refer:

§ Operational;
§ Resuscitation halls of hospitals;
§ The exhibition halls of museums;
§ Chemical laboratories of universities and research institutes;
§ Powder;
§ archives.

The insolation regime is estimated by the duration of insolation during the day, the percentage of the insulated area of \u200b\u200bthe room and the amount of radiation heat entering through the opening of the room. The optimal insolation efficiency is achieved by the daily continuous irradiation of the direct solar rays of the premises for 2.5 - 3 hours. Natural insolation lighting

Ў depending on the orientation of windows of buildings on the sides of light distinguishes three types of insolation mode: the maximum, moderate, minimum. (Appendix, Table 1).

With a western orientation, a mixed insolation mode is created. In terms of duration, it corresponds to a moderate, heating air - the maximum insolation regime. Therefore, according to SNiP 2.08.02-89, the orientation to the west of the windows of the chambers of intensive therapy, children's chambers (up to 3 years), games for games in children's departments is not allowed.

In medium latitudes (territory of the Republic of Belarus) for hospital chambers, day-staying rooms of patients, classes, group rooms of children's institutions of the best orientation, providing sufficient illumination and insolation of premises without overheating, is the southern and southeastern (permissible - UZ, B).

North, north-west, northeast oriented windows of operating, resuscitation, dressing, procedural offices, generic halls, therapeutic and surgical and surgical cabinets, which ensures uniform natural lighting of these rooms with scattered light, eliminates the overheating of the rooms and the blinding effect of the sun rays, and Also the occurrence of brilliance from the medical instrument.

Rationing and evaluation of natural lighting

The rationing and hygienic assessment of the natural lighting of existing and designed buildings and premises is performed according to SNIP II-4-79 lighting (instrumental) and geometric (calculated) methods.

The main lighting of the natural lighting of the room is the natural light (CEO) ratio of the natural light, created at some point of the specified plane indoors with the light of the sky, to the simultaneous value of the outer horizontal illumination created by the light of the fully open skill (excluding direct sunlight), expressed in Percent:

Keo \u003d E1 / E2 · 100%,

where E1 is illumination indoors, LCs;

E2 - outdoor illumination, LC.

This coefficient is an integral indicator that determines the level of natural illumination, taking into account all factors affecting the conditions for the distribution of natural light in the room. Measuring the illumination on the working surface and in the open-air is produced by a luxmeter (Y116, YU117), the principle of operation of which is based on the transformation of the energy of the light flux into the electric current. The perceiving part is a selenium photocell having light-absorbing filters with coefficients 10, 100 and 1000. The photo-element of the device is connected to the galvanometer, the scale of which is separated into suites.

Prime to work with a luxmeter must be followed by the following requirements (MU RB 11.11.12-2002):

· The receiving plate of the photocell must be placed on the working surface in the plane of its location (horizontal, vertical, inclined);
· The photocell should not fall random shadows or shadows from humans and equipment; If the workplace shall be shaded during the work of the operating or protruding parts of the equipment, the illumination should be measured in these real conditions;
· Measuring instrument should not be located near sources of strong magnetic fields; No installation of the meter on metal surfaces is not allowed.

The coefficient of natural illumination (according to the SNB 2.04.05-98) is normalized for different premises, taking into account their purpose, the nature and accuracy of the accelerated work. In total, there are 8 discharges of accuracy of viewing work (depending on the smallest size of the object of distinction, mm) and four divorces in each discharge (depending on the contrast of the observation object with the background and the characteristic of the background itself - light, medium, dark). (Appendix, Table. 2).

In case of lateral unilateral lighting, the minimum value of the CEO is normal at the point of the conditional surface (at the level of the workplace) at a distance of 1 m from the wall that is most remote from the light opening. (Appendix, Table 3).

ЎGeometric method of assessing natural lighting:

1) Luminous coefficient (SC) - the ratio of the glazed area of \u200b\u200bwindows to the floor area of \u200b\u200bthis room (the numerator and denominator of the fraction is 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) The depth coefficient (plug) (KZ) is the ratio of the distance from the light to the opposite wall to the distance from the floor to the top edge of the window. The KZ should not exceed 2.5, which is ensured by the width of the pendant (20-30 cm) and the depth of the room (6 m). However, not the SC, not KZ do not take into account the darkening of windows with opposing buildings, so additionally determine the angle of the fall of the light and the angle of the opening.
3) The incidence of the fall shows where the rays of light fall on the horizontal work surface. The angle of the fall is formed outgoing from the point of assessment of the lighting conditions (workplace) with two lines, one of which is directed to the window along the horizontal surface, the other is to the upper edge of the window. It should be equal to no less than 270.
4) The angle of the opening gives an idea of \u200b\u200bthe value of the visible part of the sky, illuminating the workplace. The angle of the hole is formed outgoing from the measurement point by two lines, one of which is directed to the upper edge of the window, the other to the upper edge of the opposing building. It should be equal to at least 50.

The evaluation of the angles of the fall and the holes should be carried out in relation to the most remote work from the window. (Appendix, Fig. 1).

Natural lighting is used for overall lighting of production and utility rooms. It is created by the radiant energy of the Sun and the human body acts the most favorable. Using this type of lighting, the meteorological conditions and their changes during the day and periods of the year in this area should be taken into account. This is necessary in order to know how much of the natural light will fall into the room through the lightning lights of the building: windows - with lateral lighting, light lights of the upper floors of the building - at the top lighting. When combined natural lighting, side light is added to the upper light.

Premises with a permanent stay of people should have natural lighting. The dimensions of light opening established by the calculation is allowed to be changed by +5, -10%.

Sunscreen devices in public and residential buildings should be provided in accordance with the heads of the SNIP on the design of these buildings, as well as with the heads for construction heat engineering.

The following types of natural lighting of premises are distinguished:

side one-sided - when light openings are located in one of the exterior walls of the room,

Figure 1. Side one-sided natural lighting

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

Figure 2. Side Natural Lighting

top - when lights and light opening in the coating, as well as light openings in the wall height differences of the building,
combined - light openings provided for lateral (top and side) and upper lighting.

The principle of normalization of natural lighting

The quality of illumination with natural light is characterized by a natural light coefficient to eOwhich represents the illumination ratio on the horizontal surface indoors to simultaneously horizontal illumination outside,

whereE. in- horizontal illumination indoors in the LC;

E. n.- horizontal illumination outside in the LC.

In the lateral lighting, the minimum value of the natural illumination coefficient is normal - to eO Min, and with upper and combined lighting - its average value - to eO cf.. The method of calculating the coefficient of natural illumination is given in sanitary standards for the design of industrial enterprises.

In order to create the most favorable working conditions, norms of natural light have been established. In cases where natural illumination is insufficient, work surfaces should be additionally lit by artificial light. Mixed lighting is allowed under the condition of additional lighting of only working surfaces with general natural light.

Construction standards and rules (SNiP 23-05-95) The coefficients of natural lighting of industrial premises are established depending on the nature of the work according to the degree of accuracy.

To maintain the necessary illumination of premises, the norms provide for the mandatory cleaning of windows and light lamps from 3 times a year to 4 times a month. In addition, it is necessary to systematically clean the walls, equipment and painting them into bright colors.

The norms of natural lighting of industrial buildings, reduced to normalization K.E.O., are presented in SNiP 23-05-95. To facilitate the rationing of the illumination of jobs, all visual work is divided into eight discharges according to the degree of accuracy.

Snip 23-05-95 establishes the required value 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 \u200b\u200bof K.E.O. Defined by the formula:

whereN. - number of the group of the administrative and territorial district for the provision of natural light;

e. n.- The value of the natural light coefficient chosen by SNiP 23-05-95, depending on the characteristics of visual works in this room and the natural lighting system.

m. N.- The luminous climate coefficient, which is located on the SNiP tables depending on the type of light opening, their orientation on the parties to the horizon and the number of the group of the administrative area.

To determine the compliance of natural illumination in the production room, the required standards are measured at upper and combined lighting-at different points of the room, followed by averaging; In the side of the least illuminated workplaces. At the same time, the outer illumination is measured and determined by the calculation by K.E.O. Compared with regulatory.

Design of natural lighting

1. Projecting the natural lighting of buildings should be based on the study of labor processes performed in the premises, as well as on the light-firmic features of the construction site of buildings. The following parameters must be defined:

characteristic and discharge of visual works;
a group of administrative district in which the construction of the building is expected;
the normalized value of the CEO, taking into account the nature of the visual works and the light-gravatical features of the location of buildings;
required uniformity of natural lighting;
the duration of the use of natural lighting during the day for various months of the year, taking into account the designation of the room, the mode of operation and the light climate of the area;
the need to protect the room from the blinding of sunlight.

2. Design of natural lighting of the building should be performed in the following sequence:

1st stage:
- determination of requirements for natural lighting of premises;
- selection of lighting systems;
- selection of types of light opening and light-resistant materials;
- the choice of means to limit the blinding effect of direct sunlight;
- accounting of the orientation of the building and lighting openings on the sides of the horizon;
2nd stage:
- performing the preliminary calculation of the natural lighting of the premises (determination of the required area of \u200b\u200blight openings);
- refinement of the parameters of light opening and premises;
3rd stage:
- performing the verification calculation of natural lighting of the premises;
- definition of premises, zones and plots that have insufficient natural lighting;
- determination of requirements for additional artificial lighting of premises, zones and sections with insufficient natural lighting;
- determination of requirements for operation of light openings;
4th stage: making the necessary adjustments to the project of natural lighting and repeated verification calculation (if necessary).

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

appointment and adopted architectural and planning, volume and spatial and constructive solution of the building;
requirements for natural lighting of premises arising from the features of production technology and visual work;
climatic and light-firmic features of the construction site;
the economy of natural lighting (for energy costs).

4. The upper and combined natural lighting should be used mainly in single-storey public buildings of a large area (covered markets, stadiums, exhibition pavilions, etc.).

5. Side natural lighting should be used in multi-storey public and residential buildings, single-storey residential buildings, as well as in single-storey public buildings, in which the ratio of the depth of rooms to the height of the upper face of the light opening over the conditional working surface does not exceed 8.

6. When choosing light opening and light-resistant materials, it should be considered:

requirements for natural lighting of premises;
appointment, volume and spatial and constructive solution of the building;
orientation of the building on the sides of the horizon;
climatic and light-gravatical features of the construction site;
the need to protect premises from insolation;
the degree of air pollution.

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

8. The translucent fillings of lighting in residential and public buildings are chosen taking into account the requirements of SNiP 23-02.

9. In the lateral natural lighting of public buildings with increased requirements for the constancy of natural light and sunscreen (for example, art galleries), light openings should be oriented to the northern quarter of the horizon (C-SZ-S-SV).

10. The choice of devices for protection against the blinding effect of direct sunlight should be made with regard to:

orientation of light openings on the sides of the horizon;
the directions of sunlight relative to a person in a room having a fixed line of view (a student at the desk, a drawing board for a drawing board, etc.);
time of day and year, depending on the purpose of the premises;
the differences between sunny time, which built solar cards, and maternity times adopted in the Russian Federation.

11. With a single work (educational) process and during the operation of premises mainly in the first half of the day (for example, lecture audiences), when the premises are oriented towards the Western quarter of the horizon, the use of sunscreens is optional.

When illuminating industrial premises use daylight, carried out by direct and reflected light light.

From a physiological point of view, natural lighting is most favorable for a person. During the day, it changes in fairly wide limits depending on the state of the atmosphere (cloudiness). The light, hitting the room, repeatedly reflected from the walls and the ceiling, falls on the illuminated surface in the expired point. Thus, the illumination in the exposed point is made up of the sum of illumination.

Structurally natural lighting is divided into:

side(one-, bilateral) - carried out through light opening (windows) in the outer walls;

top - through light openings located at the top (roof) of the building;

combined- Combination of upper and lateral lighting.

Natural lighting is characterized by the fact that the created illumination varies depending on the time of day, year, meteorological conditions. Therefore, as a criterion for assessing natural lighting, a relative value is adopted - natural light coefficient(KEO), or e.not dependent on the above parameters.

Natural Light Coefficient (CEO) - the lighting ratio at this point indoors E. vN To the simultaneous value of the outer horizontal illumination E. n. created by the light of a fully open skill (not closed by buildings, structures, trees) expressed as a percentage, i.e.:

(8) where E. vN - illumination indoors at a checkpoint, LC;

E. n. - At the same time measured illumination outside the room, LC.

For measuring Actual CEO requires simultaneous measurements Illumination indoors E. vN at a control point and outdoor illumination on the horizontal platform under open skill E. n. , free from objects(buildings, trees ) closing individual parts of the sky. CEO measurements can only be carried out. with continuous uniform decadeal clouds(solid cloudiness, lumens are absent). Measurements are carried out by two observers with two luxmeters, at the same time (observers must be equipped with chronometers).

Control Points For measurements, they must be selected in accordance with GOST 24940-96 "Buildings and structures. Methods for measuring lighting. "

Keo values \u200b\u200bfor different premises are in the range of 0.1-12%. Normation of natural lighting is carried out in accordance with SNiP 23-05-95 "Natural and Artificial Lighting".

In small rooms with unilateral side Lighting is normalized (i.e., actual illumination is measured and compared with norms) minimum keo value At a point located at the intersection of the vertical plane of the characteristic section of the premises and the conditional working surface at a distance of 1 m from the wall, most remote from light openings.

Working surface - The surface on which work is performed and on which the illumination is normalized or is measured.

Conditional working surface - horizontal surface at an altitude of 0.8m from the floor.

Characteristic section of the room - This is a cross-section in the middle of the room, the plane of which is perpendicular to the plane of glazing light openings (with lateral lighting) or the longitudinal axis of the spans of the room.

For bilateral sides Lighting normal minimum keo value - In the plane in the middle premises.

IN large-sizedindustrial premises sidelighting The minimum Keo value is normalized at the point, remote from light openings:

by 1.5 heights of the room - for the work of i -IV discharges;

2 heights of the room - for the works of V-VII discharges;

on 3 heights of the room for work VIII discharge.

For upper and combined Lighting is normalized average Keo value At points located at the intersection of the vertical plane of the characteristic section of the room and the conditional working surface or the floor. The first and last points are taken at a distance of 1 m from the surface of the walls or partitions.

(9)

where e. 1 E. 2 ..., e n. - CEO values \u200b\u200bat selected points;

n. - the number of light control points.

It is allowed to divide the room on zones with various conditions of natural lighting, the calculation of natural lighting is made in each zone independently of each other.

For insufficient norms natural lighting in the production facilities of it complement artificial lighting. This light is called combined .

In the production premises with visual work of the I-III of the discharges, combined lighting should be arranged.

In large-pool assembly shops, in which work is carried out in a significant part of the room at different levels from the floor and on various working surfaces, the upper natural lights are used in the space.

Natural light should evenly illuminate jobs. For upper and combined natural lights determine unevenness natural lighting of industrial premises that should not exceed 3: 1 for work I-VI Speakers in visual conditions, i.e.

(10)

Defined table 1. Snip 23-05-95 CEO value, refined taking into account the characteristics of the visual work, the lighting system, location of buildings in the countryaccording to the formula

, (11)

where N. - the number of the security group with natural light (adj. D SNIP 23-05-95);

e. n. - the coefficient of natural lighting (Table 1 SNiP 23-05-95);

m. N. - The light climate coefficient, determined depending on the area of \u200b\u200bthe location of the building on the territory of the country and the orientation of the building relative to the parties to the light (cm. Table 4 SNiP 23-05-95).