Harmful production factors - industrial lighting. Requirements for rational lighting. Workplace lighting parameters ▼Geometric method for assessing natural lighting

Artificial lighting should be sufficient, uniform, without glare or shadows. It can be general, local combined. At catering establishments, as a rule, general lighting of production premises is used, which should provide uniform illumination of the entire room, and for better illumination of workplaces, general localized lighting with a distribution of luminous flux. At distribution points, in confectionery shops, and in administrative premises, it is most rational to use combined lighting, combining general and local. The use of local lighting only is not allowed.

The light sources used are mainly fluorescent or incandescent lamps. Preference should be given to fluorescent lamps.

Fluorescent lamps produce light similar in spectrum to daylight; they are more economical due to greater light output with low thermal radiation and a longer service life compared to incandescent lamps. The disadvantages of fluorescent lamps include pulsation of the light flux, which results in a stroboscopic effect when moving and rotating parts of mechanisms are perceived as stationary, which leads to injury. In low light conditions, fluorescent lamps give a “twilight” effect, so when using them, a high level of illumination is required. Incandescent lamps are significantly inferior to fluorescent lamps in terms of hygienic indicators: their filament brightness is higher than acceptable for the eyes, they give a high thermal effect, the light of these lamps differs sharply from daylight.

Lamps, according to the nature of the lighting fixtures and the distribution of the light flux, are divided into predominantly direct light (60...80% of the flux is directed downwards), diffused light (uniform distribution of the flux) and predominantly reflected light (60...80% of the flux is directed upwards). Direct light fixtures are more often used. They illuminate work surfaces well, but produce harsh shadows. Lamps of diffused and reflected light can be used provided that the ceiling and walls have a reflectance of at least 60%.

To illuminate industrial premises and warehouses, lamps equipped with moisture and dust protection equipment are used. To avoid glass fragments getting into food at catering establishments, it is not allowed to illuminate production premises with lamps open at the bottom. Lighting fixtures must have protective fittings and must be cleaned and washed regularly.

Workplaces should not be shiny. Fluorescent lamps placed in rooms with rotating equipment (universal drives, cream whipping machine, dough mixers, circular knives) must have lamps installed in antiphase. General lighting fixtures are placed evenly throughout the room. Lamps are not placed above stoves, technological equipment, or cutting tables. If necessary, workplaces are equipped with additional lighting sources.

Illumination indicators for industrial premises must comply with established standards. To determine illumination, a special device is used - a lux meter.

In accordance with hygienic requirements, the illumination on a horizontal plane at a level of 0.8 m from the floor should be (in lux):

in confectionery shops and dispensers - 300;

in dining rooms (except restaurants), buffets, hot and cold shops, pre-cooking and procurement shops, washing kitchen and tableware - 200;

containers in loading and storage rooms - 75;

In vegetable pantries and refrigerated chambers, when using incandescent lamps, an illumination of 20 lux (at floor level) is allowed. In administrative premises, illumination at a level of 0.3 m from the floor should be 200 lux, and in lobbies, cloakrooms, and main corridors - 75 lux (at floor level).

Cylindrical illumination, which characterizes the saturation of the room with light, in dining rooms, on visitors’ tables and on dance floors should be at least 75 lux. The discomfort index is also normalized to assess brightness when the field of view is unevenly bright. It should be no more than 60% for all premises except the confectionery shop. For this workshop, the discomfort rate should not exceed 40%.

The light pulsation coefficient is an important criterion for assessing the performance of fluorescent lamps and should be no more than 15...20% for different premises of the enterprise.

The levels of illumination in the premises of a public catering establishment are examined during production control (at least once a year).

Artificial lighting can be general, local or combined.

The hygienic assessment of artificial lighting includes: determining the level of illumination of the required area, characterizing the light source and fittings.

Illumination is the ratio of the luminous flux incident on a surface to the area of this surface. Express illumination in lux (lx).

When calculating illumination, the following are taken into account: the complexity of the technological process and, consequently, the degree of visual strain; duration and intensity of visual work; contrast between the lighting of the workplace and the surrounding background.

Light sources are incandescent and fluorescent lamps. Their hygienic characteristics are different and are determined by the following properties of the lamps:

The share of energy converted by the lamp into light;

Thermal radiation;

Spectral characteristics of visible radiation;

Stable luminous flux.

Electric incandescent lamps are light sources with an emitter in the form of a tungsten filament or spiral, heated by electric current to 2500-3300 oC. The higher the filament temperature, the larger part of the emitted energy is perceived in the form of light, i.e. the more economical the lamp is. However, as the filament temperature of tungsten increases, the rate of its evaporation also increases, which shortens the life of the lamp. Currently, in order to reduce the rate of tungsten evaporation and make lamps more economical, they are filled with a krypton-xenon mixture. Since the presence of inert gas causes additional power losses, low-power lamps (40 W or less), which have the lowest efficiency, are made hollow (vacuum).

Incandescent lamps have a number of disadvantages:

Low efficiency;

Strong thermal radiation;

A small fraction of energy converted into light - (vacuum about 7%, krypton-xenon - up to 13%);

The lamp filaments are extremely bright to the eye;

Unlike daylight, visible radiation is dominated by yellow and red parts of the spectrum, which makes color perception and color discrimination difficult;

The light flux contains almost no ultraviolet rays characteristic of sunlight.

Fluorescent lamps are characterized by double energy conversion: electrical energy is converted into ultraviolet radiation energy, and ultraviolet radiation energy into the visible glow of luminescent substances.

A fluorescent lamp is a sealed glass tube filled with mercury vapor and argon. A fine-crystalline luminescent substance is applied to the inner surface of the tube. Electrodes made of tungsten spirals are soldered into both ends of the tube. An electric current passing through a gaseous medium between the electrodes causes the mercury vapor to glow and form UV rays. By affecting the phosphor, ultraviolet rays cause it to glow.

Depending on the type of phosphor and the proportion of the mixture, fluorescent light (DS), white light (WL), cool white light (CWL) and warm white light (WL) lamps are produced. Fluorescent lamps are characterized by insignificant radiation in the red part of the spectrum, which brings their radiation closer to daylight, but at the same time distorts the transmission of red and orange tones. BS and TBS lamps produce less intense radiation in the blue violet region than DS lamps. Therefore, fluorescent lamps are used to illuminate rooms that require a subtle difference in colors and shades.

The energy converted into light in fluorescent lamps is 3-4 times greater than incandescent lamps, and thermal radiation is negligible. The service life of fluorescent lamps is 3 times longer than incandescent lamps.

However, a serious disadvantage of fluorescent lamps is the fluctuation of the luminous flux - the stroboscopic effect. It represents multiple imaginary images of moving objects, which causes visual fatigue, distorted perception of moving objects and can cause occupational injuries. To prevent the stroboscopic effect, it is necessary to turn on several closely spaced fluorescent lamps in different phases of a three-phase electrical network.

The above differences in the hygienic assessment of light sources are taken into account when choosing them for lighting rooms for various purposes.

For lighting industrial premises, it is recommended to use mainly incandescent lamps. In warehouses, lamps with fluorescent lamps and incandescent lamps should be used. In storerooms, incandescent lamps in lamps must be covered with silicate glass.

The brightness of the luminous surface of fluorescent lamps is insignificant, but to prevent visual fatigue, they, like incandescent lamps, are enclosed in special fittings.

The fixture is a device designed to rationally redistribute the light flux, protect the eyes from excessive brightness, protect the light source from mechanical damage, and the environment from fragments in the event of possible destruction of the lamp.

An important hygienic characteristic of fittings is light distribution, i.e. distribution of illumination in space. When choosing a lamp, in addition to light distribution, the degree of protection of the light source from environmental influences is taken into account, which is especially important in damp, dusty rooms, rooms with a chemically active environment, etc.

Lamps (light sources in fittings), depending on the distribution of light, are divided into four groups:

Direct light luminaires - direct about 90% of the light onto the illuminated surface, but sharp shadows and glare may appear on them.

Lamps with predominantly reflected light - their lower spherical part is made of milk glass, and the upper part is made of frosted glass. In this case, about 65-70% of the light flux is directed to the upper part of the lamp. Such lamps are used in those rooms where diffuse lighting is required.

Reflected light fixtures - direct the entire luminous flux to the ceiling. Rays of light are reflected at different angles from the ceiling and the top of the walls, as a result of which shadows almost completely disappear.

Ambient light lamps create quite satisfactory lighting conditions: their glare is insignificant, and no sharp shadows are formed on the illuminated surfaces. However, they, like reflected light lamps, absorb a significant portion of the light.

It is prohibited to use lamps with reflectors or diffusers made of flammable materials. In refrigerated food chambers, luminaires approved for low temperatures should be used. Lamps must have protective shades with a metal mesh to prevent damage and glass from getting on products. An important hygienic requirement is the timely cleaning of lamps, since dirty fittings reduce the illumination of workplaces by 25-30%.

At food enterprises, natural and artificial lighting is designed in accordance with the requirements of SNiP “Natural and artificial lighting. Design standards".

Sanitary requirements for lighting of public catering establishments. Natural and artificial lighting in all production, warehouse, sanitary and administrative premises must comply with sanitary rules. In this case, natural light should be used as much as possible. Illumination indicators for industrial premises must comply with established standards.

For the cold shop and premises for preparing cream and finishing cakes and pastries in the confectionery shop, a northwest orientation is provided, as well as protection from insolation (blinds, special glass and devices that reflect thermal radiation).

To illuminate industrial premises and warehouses, it is necessary to use lamps in a moisture-proof design. Workplaces should not be shiny. Fluorescent lamps placed in rooms with rotating equipment (universal drives, dough mixers, cream beaters, disc knives) must have lamps installed in antiphase. Lamps should not be placed above stoves, technological equipment, or cutting tables. If necessary, workplaces are equipped with additional lighting sources. Lighting devices must have protective fittings.

The glazed surfaces of windows and openings, lighting fixtures and fittings must be kept clean and cleaned when dirty.

More on the topic Hygienic requirements for artificial lighting:

Hygienic requirements for natural and artificial lighting of pharmacies, warehouses for small wholesale trade of pharmaceutical products.

Artificial lighting can be general, local or combined.
The hygienic assessment of artificial lighting includes: determining the level of illumination of the required area, characterizing the light source and fittings.
Illumination - the ratio of the luminous flux incident on a surface to the area of this surface. Express illumination in lux (lx).
When calculating illumination, the following are taken into account: the complexity of the technological process and, consequently, the degree of visual strain; duration and intensity of visual work; contrast between the lighting of the workplace and the surrounding background.
Sources of light - incandescent and fluorescent lamps. Their hygienic characteristics are different and are determined by the following properties of the lamps:
the share of energy converted by the lamp into light;

Electric incandescent lamps- these are light sources with an emitter in the form of a tungsten filament or spiral, heated by electric current to 2500-3300 o C. The higher the filament temperature, the greater the part of the emitted energy is perceived in the form of light, i.e. the more economical the lamp is. However, as the filament temperature of tungsten increases, the rate of its evaporation also increases, which shortens the life of the lamp. Currently, in order to reduce the rate of tungsten evaporation and make lamps more economical, they are filled with a krypton-xenon mixture. Since the presence of inert gas causes additional power losses, low-power lamps (40 W or less), which have the lowest efficiency, are made hollow (vacuum).
Incandescent lamps have a number of disadvantages:
low efficiency;

strong thermal radiation;

a small fraction of energy converted into light - (vacuum about 7%, krypton-xenon - up to 13%);

lamp filaments are extremely bright to the eyes;

unlike daylight, visible radiation is dominated by yellow and red parts of the spectrum, which complicates color perception and color discrimination;

The light flux contains almost no ultraviolet rays characteristic of sunlight.

Fluorescent lamps characterized by double energy conversion: electrical energy is converted into ultraviolet radiation energy, and ultraviolet radiation energy into the visible glow of luminescent substances.
A fluorescent lamp is a sealed glass tube filled with mercury vapor and argon. A fine-crystalline luminescent substance is applied to the inner surface of the tube. Electrodes made of tungsten spirals are soldered into both ends of the tube.

An electric current passing through a gaseous medium between the electrodes causes the mercury vapor to glow and form UV rays. By affecting the phosphor, ultraviolet rays cause it to glow.
Depending on the type of phosphor and the proportion of the mixture, fluorescent light (DS), white light (WL), cool white light (CWL) and warm white light (WL) lamps are produced. Fluorescent lamps are characterized by insignificant radiation in the red part of the spectrum, which brings their radiation closer to daylight, but at the same time distorts the transmission of red and orange tones. BS and TBS lamps produce less intense radiation in the blue violet region than DS lamps. Therefore, fluorescent lamps are used to illuminate rooms that require a subtle difference in colors and shades.
The energy converted into light in fluorescent lamps is 3-4 times greater than incandescent lamps, and thermal radiation is negligible. The service life of fluorescent lamps is 3 times longer than incandescent lamps.
However, a serious disadvantage of fluorescent lamps is the fluctuation of the luminous flux - stroboscopic effect. It represents multiple imaginary images of moving objects, which causes visual fatigue, distorted perception of moving objects and can cause occupational injuries. To prevent the stroboscopic effect, it is necessary to turn on several closely spaced fluorescent lamps in different phases of a three-phase electrical network.
The above differences in the hygienic assessment of light sources are taken into account when choosing them for lighting rooms for various purposes.
For lighting industrial premises It is recommended to use predominantly incandescent lamps. In warehouses, lamps with fluorescent lamps and incandescent lamps should be used. In storerooms, incandescent lamps in lamps must be covered with silicate glass.
The brightness of the luminous surface of fluorescent lamps is insignificant, but to prevent visual fatigue, they, like incandescent lamps, are enclosed in special fittings.
Armature is a device designed to rationally redistribute the light flux, protect the eyes from excessive brightness, protect the light source from mechanical damage, and the environment from fragments in the event of possible destruction of the lamp.
An important hygienic characteristic of fittings is light distribution, i.e. distribution of illumination in space. When choosing a lamp, in addition to light distribution, the degree of protection of the light source from environmental influences is taken into account, which is especially important in damp, dusty rooms, rooms with a chemically active environment, etc.
Lamps (light sources in fittings), depending on the distribution of light, are divided into four groups:
Direct light fixtures - direct about 90% of the light onto the illuminated surface, but sharp shadows and glare may appear on them.
Lamps with predominantly reflected light - their lower spherical part is made of milk glass, and the upper part is made of frosted glass. In this case, about 65-70% of the light flux is directed to the upper part of the lamp. Such lamps are used in those rooms where diffuse lighting is required.
Indirect light fixtures - direct the entire light flux to the ceiling. Rays of light are reflected at different angles from the ceiling and the top of the walls, as a result of which shadows almost completely disappear.
Ambient light fixtures - create quite satisfactory lighting conditions: their glare is insignificant, no sharp shadows are formed on the illuminated surfaces. However, they, like reflected light lamps, absorb a significant portion of the light.
It is prohibited to use lamps with reflectors or diffusers made of flammable materials. In refrigerated food chambers, luminaires approved for low temperatures should be used. Lamps must have protective shades with a metal mesh to prevent damage and glass from getting on products. An important hygienic requirement is the timely cleaning of lamps, since dirty fittings reduce the illumination of workplaces by 25-30%.
At food enterprises, natural and artificial lighting is designed in accordance with the requirements of SNiP “Natural and artificial lighting. Design standards".
Sanitary requirements for lighting of public catering establishments. Natural and artificial lighting in all production, warehouse, sanitary and administrative premises must comply with sanitary rules. In this case, natural light should be used as much as possible. Illumination indicators for industrial premises must comply with established standards.
For the cold shop and premises for preparing cream and finishing cakes and pastries in the confectionery shop, a northwest orientation is provided, as well as protection from insolation (blinds, special glass and devices that reflect thermal radiation).
To illuminate industrial premises and warehouses, it is necessary to use lamps in a moisture-proof design. Workplaces should not be shiny. Fluorescent lamps placed in rooms with rotating equipment (universal drives, dough mixers, cream beaters, disc knives) must have lamps installed in antiphase. Lamps should not be placed above stoves, technological equipment, or cutting tables. If necessary, workplaces are equipped with additional lighting sources. Lighting devices must have protective fittings.
The glazed surfaces of windows and openings, lighting fixtures and fittings must be kept clean and cleaned when dirty.

Nitrogen is an element of the 15th group (according to the outdated classification - the main subgroup of the fifth group) of the second period of the periodic table of chemical elements of D.I. Mendeleev, with atomic number 7. It is designated by the symbol N (lat. Nitrogenium). The simple substance nitrogen (CAS number: 7727-37-9) is a fairly inert diatomic gas without color, taste and smell (formula N2) under normal conditions, of which three-quarters of the earth’s atmosphere consists.

Biological role

Nitrogen is an element necessary for the existence of animals and plants; it is part of proteins (16-18% by weight), amino acids, nucleic acids, nucleoproteins, chlorophyll, hemoglobin, etc. In the composition of living cells, the number of nitrogen atoms is about 2%, by mass fraction - about 2.5% (fourth place after hydrogen, carbon and oxygen). In this regard, a significant amount of fixed nitrogen is contained in living organisms, “dead organic matter” and dispersed matter of the seas and oceans. This amount is estimated at approximately 1.9 1011 tons. As a result of the processes of rotting and decomposition of nitrogen-containing organic matter, subject to favorable environmental factors, natural deposits of minerals containing nitrogen, for example, “Chilean saltpeter” (sodium nitrate with admixtures of other compounds), Norwegian, Indian saltpeter.

Purpose of the lesson:study the hygienic requirements for natural and artificial lighting, master methods for determining and assessing the indicators of natural and artificial lighting in premises.

In preparation for the lesson, students must work through the following: theoretical issues.

1. Composition of solar radiation. Biological and hygienic significance of the rays of the solar spectrum. General hygienic requirements for lighting.

2. Natural light. Factors influencing the natural illumination of premises. Indicators for assessing and normalizing the level of natural lighting in premises for various purposes.

3. Hygienic requirements for artificial lighting of premises. Light sources, their hygienic assessment. Lighting systems. Characteristics of different types of lamps and light-protective fittings.

4. Methods of assessment and standardization of artificial lighting of industrial premises.

After mastering the topic the student must know:

Methodology for conducting hygienic inspection of industrial lighting;

Determination of the insolation regime of premises;

Carrying out instrumental and calculation determinations of natural and artificial illumination of pharmacy premises;

be able to:

Assess the state of natural and artificial lighting in the premises of pharmacies based on the results of studies for compliance with hygienic standards;

Assess the working conditions of pharmacy staff based on the factor “light environment”;

Use basic regulatory documents and reference information sources to develop hygienic recommendations for improving the lighting of pharmacy premises.

Training material for completing the assignment

The optical range of electromagnetic radiation from the Sun, reaching the boundaries of the earth's atmosphere (from 100 to 60,000 nm), is conventionally divided into three parts (infrared, ultraviolet and visible parts of the solar spectrum), since the properties of radiant energy change with changes in the length of electromagnetic waves.

UV radiation from the Sun in the range of 10-200 nm is completely spent on the formation of the ionosphere at an altitude of 50-80 km from the Earth's surface. Short-wave UV radiation in the range of 200-280 nm (UV-C), which has a pronounced bactericidal action does not reach the surface of the Earth; Most of it is spent in the stratosphere at an altitude of 20-25 km for the formation of the ozone layer, the rest is absorbed by oxygen in the troposphere. The part of UV radiation that reaches the surface of the Earth and directly affects the nature of the Earth and humans is long-wave, 400-320 nm (UV-A), and medium-wave, 320-280 nm (UV-B). In industrial cities, especially in winter, UV radiation from the sun is completely absorbed by man-made components of urban air (for example, nitrogen oxides) and does not enter the room. Only a small part of UV radiation with a wavelength of 300-400 nm can enter the premises, since UV radiation shorter than 300 nm is blocked by ordinary window glass containing oxides of titanium, chromium and iron. Special uviol glasses transmit UV rays with a wavelength of up to 254.4 nm.

UV rays are the most biologically active of the entire range. UV-A causes so-called early pigmentation due to the formation of the melanin pigment from the amino acid tyrosine, which causes the tanning effect, as well as, with a sufficient dose, erythema, which is a specific reaction of the skin to UV radiation. UV-B influences the maintenance of normal phosphorus-calcium metabolism due to the synthesis of cholecalciferol (vitamin D 3) from dehydrocholesterol. Without endogenous synthesis of vitamin D3, its deficiency is observed even with an adequate diet, especially in children. In areas characterized by a lack of UV radiation, it is necessary to organize preventive UV irradiation in organized high-risk groups (preschool institutions, some work groups - miners, metro workers) using artificial sources. However, UV rays in case of overdose can have a negative effect on a person in the form of damage to the structure of the DNA molecule, which can lead to death, mutations or tumor degeneration of the cell. UV radiation with a wavelength of 240-313 nm has a blastomogenic effect. In addition, under the influence of UV rays reflected from the sunlit surface of snow or ice, it may develop ophthalmia - keratoconjunctivitis. The amount of UV radiation that causes barely noticeable redness in the skin of an untanned person after 6-10 hours is called erythema or threshold dose. The optimal dose of UV rays is 1/3-1/6 of the erythemal dose. Prevention of light starvation requires the use of artificial UV irradiation.

The main effect of solar infrared radiation (EMR with a wavelength greater than 760 nm) is thermal. IR rays, absorbed by body tissues, cause an increase in the temperature of the skin area and the formation of thermal erythema. In populated areas, and especially in homes, IR rays do not have a pronounced specific biological effect; however, in the conditions of the southern zone or the unfortunate orientation of a building located in the central zone, disturbances in the microclimate of the room may periodically be observed as a result of its excessive insolation in the summer, therefore, the sanitary rules provide for sun protection devices (SanPiN2.2.1/2,1.1.1076-01). To maintain a favorable indoor microclimate, artificial sources of infrared radiation are used - various devices and systems.

heating topics, and for medicinal purposes, an infrared bath, a Sollux lamp, and a Minin lamp are used.

The value of visible radiation (EMR with wavelengths from 760 to 380 nm) is large. Visible rays, acting on the visual analyzer (photosensitive cells of the eye), contribute to the transformation of light energy, as a result of which the body receives up to 90% of information about the environment (the psychophysiological value of light). The visual analyzer, due to the production of the hormone melatonin, regulates biological rhythms, i.e. the circadian system, which controls circadian rhythms of sleep and wakefulness, body temperature, hormonal secretion and other physiological functions, including cognitive activity. With a lack of sunlight in the autumn-winter season, some people develop the so-called seasonal disorder syndrome, characterized by depression, loss of energy, a desire to withdraw into oneself, as well as increased appetite and the need for sleep. Sunlight is necessary for a person to perform visual work (the social meaning of light).

All premises intended for long-term stay of people must have good natural and artificial lighting. Poor lighting conditions in residential, educational and industrial premises, combined with high visual load, can cause visual and general fatigue, contribute to the development of myopia, nystagmus and some other diseases, as well as injuries.

Daylight

Natural lighting of the premises is provided by direct sunlight (insolation), diffused light from the sky and reflected light from the opposing building and the surface of the coating. The lack of natural light causes the phenomenon of “light starvation”, i.e. a condition of the body caused by a deficiency of ultraviolet radiation and manifested in metabolic disorders and a decrease in the body’s resistance. Premises with constant occupancy should have natural light.

Natural lighting of the premises is determined by light climate, those. conditions of external natural lighting, which depend on the general climatic conditions of the area, the degree of

the transparency of the atmosphere, as well as the reflectivity of surrounding objects.

The level of natural lighting in the premises is also influenced by the geographic latitude of the area, the orientation of the building to the cardinal points, the presence of shading of windows by the opposing building, which in turn depends on the distance between them, the height and color of the walls, as well as the proximity of green spaces. The size of window openings, their shape and location are of great importance.

All these factors determine the duration and intensity of illumination of the room by direct sunlight, i.e. insolation regime of premises. The hygienic classification of the duration of insolation of premises takes into account the general health, bactericidal and psychophysiological effects of direct sunlight, as well as the optimal combination of all factors while observing the minimum values of each of them. Scattered and reflected light entering the room does not contain many parts of the solar spectrum, both visible and ultraviolet, absorbed by various objects (ground surface, trees, building walls, clouds, etc.), and therefore, from a physiological and hygienic point of view, cannot be considered complete (Table 10).

Insolation time	Hygiene assessment	Characteristics of effects
From 0 to 50 min	Expressed failure insolation	Low bactericidal effect, negative psychophysiological reaction (complaints about insufficient insolation in 80% of cases)
From 50 min to 1.5 h	Lack of insolation	High bactericidal effect, negative psychophysiological reaction (complaints about insufficient insolation in 50% of cases)
From 1.5 up to 2.5 hours	Sufficient insolation (comfort zone)	High bactericidal effect, positive psychophysiological reaction (no complaints)
More than 2.5 hours	Excessive insolation	Negative psychophysiological reaction (complaints of overheating in more than 50% of cases)

Hygienic standards for insolation are differentiated by latitude of the area for certain periods of the year, for which standard insolation time is regulated (SanPiN2.2.1/2.1.1.1076-01 “Hygienic requirements for insolation and sun protection of residential and public buildings and territories”): for the northern zone (north of 58? north latitude) from April 22 to August 22, at least 2.5 hours; for the central zone (58-48? north latitude) from March 22 to September 22, at least 2 hours; for the southern zone (south of 48? north latitude) from February 22 to October 22, at least 1.5 hours.

There are three main types of insolation regime (Table 11), as well as various options for their combinations. For example, in terms of the duration of insolation, the regime can be moderate, and in terms of temperature parameters - maximum.

Table 11.Types of insolation conditions in moderate rooms

climate zone of the northern hemisphere

Insolation mode	Orientation by cardinal directions	Insolation time, h	% insulated floor area	Thermal radiation
Insolation mode	Orientation by cardinal directions	Insolation time, h	% insulated floor area	kJ/m3	kcal/m3
Maximum	SE, SW			3300
Moderate	Yu, V		40-50	2100-300	500-550
Minimum	NE, NW			2100

The insolation regime must be taken into account when orienting rooms for various functional purposes. Orientation of windows in northern latitudes southern side provides higher levels of illumination and prolonged insolation compared to the northern direction. In middle and southern latitudes for residential, educational buildings and main production premises of pharmacies (aseptic block, assistant room, pharmacist-analyst room, packaging room, manager’s office) the best orientation to ensure sufficient illumination and insolation of rooms without overheating is southern and southeastern, eastern sides. It contributes to a certain extent to the sanitization of air, which occurs due to the penetration and exposure to sunlight, the bactericidal energy of which is sufficient to improve the internal environment of the room under normal conditions.

On north, northwest, northeast It is necessary to orientate rooms in which high insolation is not required or where exposure to direct sunlight must be prevented. These are auxiliary premises of pharmacies (material rooms, washing, distillation and sterilization rooms), hospital premises (operating rooms, intensive care units, dressing rooms, treatment rooms, catering units), classrooms for drawing, drawing, computer science and physical education rooms in children's and educational institutions, kitchens in residential buildings. This orientation ensures uniform natural lighting of the rooms and eliminates overheating. Western orientation causes overheating of premises in summer and lack of solar insolation in winter.

The illumination of the premises also depends on the degree of light reflection, which is determined by the color of the ceiling, walls, floor and equipment in the room itself. Dark colors absorb a lot of light, while light colors increase illumination due to reflected light. White color and light colors ensure reflection of light rays by 70-90%, light yellow - by 60%, light green - by 46%, natural wood color - by 40%, blue - by 25%, dark yellow - by 20%, light brown - by 15%, dark green - by 10%, blue and purple - 6-10%.

In rooms, white color is recommended for finishing the ceiling, for walls - light tones of yellow, beige, pink, green, blue, for furniture - the color of natural wood, for doors and window frames - white. Recommendations for the color design of premises should take into account the effect of visible light on the human body. Red-yellow colors have an invigorating effect, blue-violet colors have a calming effect. In the northern regions, shades of yellow and orange are recommended for painting the walls of rooms, imitating sunlight; in the southern regions, shades of greenish-blue are recommended, softening the shine of sunlight in the room.

The level of natural light is affected by the quality and cleanliness of glass, walls, ceilings, shading of windows with curtains, and the presence of tall flowers on the window sills. So, dirty walls reflect light 2 times less than recently painted ones. A sooty ceiling reduces the room's illumination by one third.

Depending on the location of the light openings, natural lighting is divided into side (through windows), top (through skylights) and combined (top and side).

Natural illumination is normalized in relative values depending on the arrival of the luminous flux of the Sun (natural illumination coefficient, luminous coefficient, angle of incidence and opening angle). For hygienic assessment of natural lighting, we use lighting engineering And geometric (graphic) research methods. Using the lighting method, they determine daylight factor (KEO). Daylight factor shows the percentage of natural illumination at an indoor workplace, created by sky light (direct or after reflection), to the simultaneous value of natural illumination on a horizontal surface outside the building in the open air.

To determine illumination, photoelectric lux meters of the Yu-116 type with a selenium photocell and a system of light filters (Fig. 11) and lux meters of the Argus-01 type with a semiconductor silicon photodiode are used. The mechanism of action of the Yu-116 lux meter is based on the conversion of the energy of the light flux into electrical energy. The sensing part of the device - a selenium photocell - is connected to a galvanometer, the scale of which is calibrated in lux. The luminous flux incident on the photocell is converted into an electric current, which is recorded by a galvanometer. Luxmeters of different types have 1, 2 or 3 scales for measuring illumination in three ranges: from 0 to 25 lx, from 0 to 100 lx and from 0 to 500 lx, as well as a set of filters, which allows you to measure illumination in a wide range (from 0.5-1 to 30-50 thousand lux).

Rice. eleven.Luxmeter Yu-116 with a set of filters

KEO values are standardized in premises depending on their functional purpose. The range of KEO values for residential premises ranges from 0.5 to 1%.

Table 12.Daylight coefficient value

for various premises of pharmacies (SNiP 23-05-95)

		Visual work category	KEO at side natural/combined lighting	Pharmacy premises
Very high accuracy	0,15-0,3		2,5/1,5	Assistant, aseptic
Medium accuracy	0,5-1,0		1,5/0,9	Shopping room
Low accuracy	1,0-5,0		1,0/0,6	Washing
Rough				Material

KEO with natural light for various pharmacy premises, depending on their functional purpose, is installed with optimal orientation of the premises and a minimum duration of insolation of their facades with direct sunlight. This takes into account the nature of visual work and the light climate. Thus, the minimum KEO values have been established for the points of the pharmacy premises that are furthest from the windows.

(Table 12).

Using the geometric method, we determine luminous coefficient (LC), penetration coefficient (KZ), angle of incidence and opening angle. Luminous coefficient expresses the ratio of the area of the light (glazed) surface of the windows, taken as a unit, to the floor area of the room. To calculate the luminous coefficient, the glazing area of the windows and the floor area (in m2) are measured, and then their ratio is calculated. The luminous coefficient in residential and preschool institutions is recommended at the level 1:5-1:6, in classrooms 1:4-1:5. When designing pharmacies, it is necessary to take into account that the SC is not lower than the specified values (Table 13).

Table 13.The value of light coefficient in pharmacy premises

Depth factor expresses the ratio of the distance from the floor to the top edge of the window to the depth of the room. The short circuit should not exceed 2.5, which is ensured by a room depth of up to 6 m.

Estimation of natural lighting only by the light coefficient and depth coefficient may turn out to be inaccurate, since the possibility of shading of windows by opposite buildings and trees is not taken into account, therefore, to clarify the estimate, it is additionally determined angle of incidence of light rays And hole angle.

Angle of incidenceshows at what angle the light rays from the window fall on the illuminated horizontal working surface in the room. In the event that, due to an opposing building or trees, not direct sunlight enters the room, but only reflected rays, their spectrum is deprived of the short-wave, most biologically effective part - ultraviolet rays. Angle of light incidence must be in the workplace at least 27?. The angle within which direct rays from the sky fall at a certain point in the room is called hole angle. Hole angle it should be at least 5?. Determination and assessment of the angles of incidence of light and openings should be carried out in relation to the workplaces furthest from the window. Characteristics and assessment of the sufficiency of natural lighting in the room are carried out in accordance with hygienic standards (Table 15).

Artificial lighting

Artificial lighting is used in rooms without natural light or when performing precise visual work with insufficient natural light during the daytime (combined lighting). Basic hygiene requirements

to artificial lighting are a sufficient level of its intensity, uniformity and constancy over time, the absence of glare and sharp shadows caused by the source, ensuring correct color rendering. The spectrum it creates should be close to the spectrum of natural sunlight.

Rational artificial lighting is ensured by the correct choice of lighting system, light sources, lamps, their placement, type of lighting fixtures, direction of the luminous flux and the nature of the light. Artificial lighting can be of three systems: general(uniform - when placing lamps in the upper zone of the room over its entire area or localized - when placing lamps taking into account the placement of equipment and workplaces), local And combined(general lighting is supplemented by local lighting). The uniformity of lighting in the room is ensured by the general lighting system. Sufficient illumination in the workplace can be achieved by using a local lighting system (table lamps). The best conditions are achieved with a combined lighting system (general + local). The use of local lighting without general lighting in office premises is unacceptable.

Currently used as sources of artificial lighting gas discharge lamps And incandescent lamps. In incandescent lamps, the glow occurs as a result of heating the tungsten filament of the lamp to high temperatures. Due to the low luminous efficiency, short service life (up to 1500 hours), and the predominance of yellowish-red colors in the spectrum of the lamp, which distorts color perception, the use of incandescent lamps is limited. Halogen incandescent lamps with a tungsten-iodine (halogen) cycle are more efficient, their luminous efficiency and service life are longer (up to 8000 hours). The spectrum of halogen incandescent lamps is close to natural light, which allows them to be used in public spaces (libraries, canteens, etc.). Incandescent lamps are mainly used for local lighting, in rooms with short-term occupancy and in cases where the use of gas-discharge lamps is impossible for technological reasons.

The gas discharge lamps used are low pressure (luminescent) and high blood pressure. Current standards (“Hygienic requirements for natural, artificial and combined lighting of residential and public buildings” SanPiN

2.2.1/2.1.1.1278-03) fluorescent lamps are accepted as the main ones for public and industrial premises due to the fact that they have significant luminous efficiency, allowing to create high levels of illumination, efficiency, have soft, diffused light and relatively low brightness, their emission spectrum is close to the spectrum of daylight. The principle of operation of fluorescent lamps is to convert the radiation of a mercury discharge into visible rays, which is achieved by excitation of phosphors with ultraviolet rays. To do this, the inner surface of the flask is coated with a special composition - phosphor, A drop of mercury is placed inside the flask to form mercury vapor. When electric current is passed through the lamp, ultraviolet radiation is generated, under the influence of which the phosphors begin to glow.

Fluorescent lamps are produced in several types depending on the composition of the phosphor. Fluorescent lamps (LD) with a bluish emission color are recommended for use in rooms with correct color discrimination. White lamps (LB) with a predominance of orange-yellow shades in their spectrum and especially cold white light lamps (CWL), white light with improved color rendering (LHE) And daylight, correct color rendering (LDC) used in residential, educational and pharmacy premises where good color rendition of the human face is required. Warm white light lamps (WLT) have a predominance in the spectrum of yellow and pink rays, therefore they are used to illuminate train stations, cinema lobbies, and subway premises.

The lamp is used to protect the eyes from the glare of the light source. The lamp consists of two parts - a light source (lamp) and lighting fixtures. From the point of view of redistribution of the luminous flux, lamps are distinguished direct, reflected and diffused light. The fittings of direct light fixtures, due to the internal reflective surface, direct about 90% of the light from the lamp to the illuminated area. Indirect light luminaires, on the contrary, direct most of the light flux upward, due to which the room is illuminated with soft, uniform diffused light, but at the same time 50% of the light is lost. Most often, in residential, educational, as well as hospital and pharmacy premises, diffused light lamps are used, which is distributed evenly throughout the room and does not produce sharp shadows and glare. To obtain

To reduce diffused light, milk or frosted glass is used in lamps.

The number of lamps and lamp power are calculated based on the level of illumination in the workplace, which must comply with established hygienic standards. The level of artificial lighting is measured directly on the horizontal surface of the workplace using a lux meter (objective method). Control points for measuring minimum illumination are placed in the center of the room, under lamps, between lamps and their rows, near walls at a distance of at least 1 m. The level of artificial lighting is measured in the dark.

In practice, when designing lighting installations and examining designs for industrial premises, calculation methods for determining illumination are often used. The most widely used method is the power density method. The number of lamps and lamp power are calculated based on the level of illumination in the workplace, which must comply with established hygienic standards.

The specific power method (watt method) is recommended for the approximate determination of artificial illumination. It is based on calculating the total power of all light sources (W) in the room and determining the specific power of the lamps (P) by dividing W by the area of the room (S) (P=W/S, W/m2). Artificial illumination is calculated by multiplying the specific power of lamps by the coefficient e, which shows what illumination (in lux) a specific power of 1 W/m 2 gives. The value of e for rooms with an area of no more than 50 m2 at a network voltage of 220 V for incandescent lamps with a power of less than 100 W is 2.0; for lamps 100 W or more - 2.5; for fluorescent lamps - 12.5.

Example.The area of the material room is 25 m2. It is illuminated by two 100 W incandescent lamps, the mains voltage is 220 V.

Specific power of lamps = (100 W * 2 lamps): 25 m 2 = 8 W/m 2.

Artificial illumination = 8 W/m2 * 2.5 = 20 lux.

The required amount of illumination at workplaces is set depending on the size of objects of discrimination, since examining small details in low light leads to a significant decrease in visual performance and

labor productivity. The norms of artificial illumination when performing visual work of varying accuracy (from I to VI categories) in pharmacy premises are given in Table. 14-15.

Table 14.Standards for artificial lighting in pharmacy premises

(SNiP 23-05-95)

Characteristics of visual work	Size of discrimination objects, mm	Visual work category	Illumination in the workplace, lux	Pharmacy premises
Very high accuracy	0,15-0,3		500-400	Assistant, aseptic
Medium accuracy	0,5-1,0		(200)150	Shopping room
Low accuracy	1,0-5,0		(200)100	Washing
Rough			50-75	Material

Table 15.Standards for natural, combined and artificial lighting of residential, educational, pharmacy and medical premises (extracts from SanPiN 2.2.1/2.1.1.1278-03)

Lighting

The name of a room	Natural/combined (KEO), %	Artificial (fluorescent lamps), lux
Living rooms	0,5/-
Pharmacy premises
Area for visitors in the sales area	-/0,4
Prescription department, manual sales, optics, finished medicines departments	-/0,6
Assistant, aseptic, analytical, packaging, procurement of concentrates and semi-finished products, control and marking	-/0,9

End of table. 15

Sterilization, washing	1,0/0,6
Storage areas for medicines, dressings and utensils
Storage areas for acids, disinfectants, flammable and flammable liquids
Pantry containers
Educational premises of schools and universities
Auditoriums, school classrooms	1,5/1,3
Auditoriums, classrooms, university laboratories	1,2/0,7
Computer science classrooms	1,2/0,7
Drawing and drawing rooms	1,5/0,7
Premises of medical institutions
operating room
Delivery, dressing, resuscitation	1,5/0,9
Preoperative	1,0/0,6
Doctors' offices	1,5/0,9
Wards for newborns, postoperative, intensive care	1,0/-
Chambers	0,5/-

Laboratory work “Determination and assessment of natural and artificial lighting in a room”

Student assignments

1. Determine the type of insolation regime in the classroom.

2. Determine the indicators of natural lighting in the classroom (light coefficient, depth coefficient) and in the workplace (KEO, angles of incidence of light and openings). Assess the natural lighting conditions of the room as a whole and your workplace.

3. Determine the illumination of the room with artificial light using objective and calculation methods. Assess the illumination and characterize the lighting system, light sources, type of fittings and the nature of light in the lamps used.

4. Write sanitary and hygienic conclusion based on a comparison of the results of determining illumination indicators with their hygienic standards (SanPiN2.2.1/2.1.1.1278-03).

Working method

1. Determining the type of insolation regime The study room is carried out taking into account the orientation of the building to the cardinal directions, shading of windows by neighboring houses, and the size of light openings.

2. Determination and assessment of natural lighting indicators in premises

Determination of natural light factor Use a lux meter to measure the natural light on

indoor workplace (E 1) and illumination of the horizontal plane outside the building (E0). Calculation daylight factor produced according to the formula:

KEO = E 1 100 / E 0, %,

where: E1 - illumination on a horizontal surface indoors;

E0 - illumination of the horizontal plane outside the building.

Determination of luminous coefficient

To calculate the luminous coefficient, measure the glazing area of the windows and the floor area (in m2), then calculate their ratio. SC is expressed as a fraction, the numerator of which is one, and the denominator is the quotient of dividing the area of the room by the surface area of the glass. Example. The glazed surface of the room's windows is equal to 4.25 m2, the floor area is 28.4 m2. SC = 1:4.25/28.4 = 1:6.

Determination of the depth coefficient

For calculation depth coefficient measure the distance from the floor to the top edge of the window, as well as the distance from the light-carrying wall to the opposite wall, then calculate their ratio. KZ is expressed as a fraction, and the numerator of the fraction is reduced to 1, for which the numerator and denominator are divided by the value of the numerator.

Determining the angles of incidence of light and apertures(Fig. 12)

The angle of incidence (a) is formed by two lines, one (CA) goes from the upper edge of the window to the point where the lighting conditions are determined, the second (AB) is a line on the horizontal plane connecting the measurement point with the wall on which the window is located.

Rice. 12.Light incidence angle (α) and opening angle (β)

The opening angle (β) is formed by two lines running from the measuring point at the workplace: one (CA) - to the upper edge of the window, the other (AD) - to the highest point of the opposing building or any fence (fence, trees, etc.). P.).

Measuring the angles of incidence and opening can be done: visually - using a ruler and protractor, graphically - by constructing a right triangle on a certain scale, as well as an optical inclinometer. To determine the angles of incidence and the opening using a graphical method, you need to use a tape measure to measure the horizontal distance from a point on the working surface to the light-carrying wall (Fig. 12 - AB). Then, from the point of intersection of this horizontal line with the wall, measure the vertical distance to the upper edge of the window (Fig. 12 - BC). Place both segments on a certain scale on the drawing. By connecting the point in the drawing corresponding to the upper edge of the window (C) with a point on the working surface (A), we obtain a right triangle, the acute angle at the base of which (α) is the angle of incidence of light. It can be measured with a protractor or using a tangent table: tanα = CB/AB. To measure the angle of the hole, it is necessary to mark a horizontal point on the surface of the window that coincides with a visual line directed from the measurement point to the upper edge of the opposing building or object. Apply this mark on the same scale on the drawing (Fig. 12 - point D) and, connecting it with the measurement point on the working surface (Fig. 12 - AD), obtain the hole angle (β), which can also be measured with a protractor or determined using tangent tables (Table 16) as the difference between angles

Tangent	Corner, hail	Tangent	Corner, hail	Tangent	Corner, hail
0,176		0,404		0,675
0,194		0,424		0,700
0,213		0,445		0,727
0,231		0,466		0,754
0,249		0,488		0,781
0,268		0,510		0,810
0,287		0,532		0,839
0,306		0,554		0,869
0,325		0,577		0,900
0,344		0,601		0,933
0,364		0,625		0,966
0,384		0,649		1,000

Characterization and assessment of the sufficiency of natural lighting in the room is carried out in accordance with the standards given in the tables.

3. Definition and evaluation of artificial lighting

Characteristics (description) artificial lighting systems (general uniform, general localized, local, combined, combined), type of light source (incandescent, fluorescent, etc.), their power, type of fittings and, in connection with this, the direction of the luminous flux and the nature of the light (direct , diffused, reflected), the presence or absence of sharp shadows and shine.

Determination of artificial light

Measure the illumination directly on the work surfaces using a lux meter;

Determine illumination using an approximate calculation method.

Sample protocol for completing the laboratory task “Hygienic assessment of natural and artificial lighting”

1. Determination and hygienic assessment of the type of insolation regime of the room under study: the orientation of the building to the cardinal points... the distance to the opposing building... its height.., the color of the walls... the distance to green spaces... the size of window openings...

2. Determination of the type of work according to the degree of accuracy (depending on the size of the object of discrimination).

3. Hygienic assessment of natural lighting:

General characteristics: in the laboratory... windows, paint color: walls... ceiling... floor... frequency of cleaning window glass.

Determination of KEO using a Yu-116 lux meter. Horizontal illumination outside the building... lux, Illumination in the workplace... lux,

KEO = ...%.

Definition of SC.

Window glazing area... m 2, floor area... m 2,

SK = ...

Definition of short circuit.

Distance from the floor to the top edge of the window... m, Distance from the light-carrying wall to the opposite wall... m,

KZ = ...

Determination of the angle of incidence of light (drawing and calculations).

Determination of the hole angle (drawing and calculations).

4. Hygienic assessment of artificial lighting:

Characteristics of artificial lighting: in the laboratory... lighting system, number of lamps... lighting source... type of lamps... number of lamps. power of one lamp... type of lighting fixtures..., lamps... light, maintenance of lighting installations and frequency of cleaning lamps.

Determination of artificial illumination.

Objective method (using a lux meter). Lighting in the workplace... lux.

By calculation method: in the laboratory, floor area... number of lamps... type of lamps... number of lamps... their power... specific power... illumination... lux.

Conclusion(sample)

1. The laboratory (pharmacy) room, taking into account the nature of visual work and the light climate, has good (not entirely satisfactory) lighting. All indicators of natural light comply with hygienic standards [certain indicators (list which ones) do not comply with hygienic standards]:

KEO = ... (indicate compliance with the standard);

Luminous coefficient = ... (indicate compliance with the standard);

Light incidence angle = ... (indicate compliance with the standard);

Hole angle = ... (indicate compliance with standard).

The selection of color finishes for the surfaces of production premises and equipment, their cleanliness does (does not) comply with hygienic requirements, based on the nature of the work being performed.

TOPIC 14. HYGIENIC ASSESSMENT OF BUILDING, LAYOUT AND OPERATION OF PHARMACY ORGANIZATIONS (PHARMACIES)

TOPIC 15. HYGIENIC REQUIREMENTS FOR WORKING CONDITIONS OF PHARMACY WORKERS

TOPIC 16. HYGIENIC ASSESSMENT OF BUILDING, LAYOUT AND OPERATION OF WHOLESALE PHARMACEUTICAL ORGANIZATIONS (PHARMACY WAREHOUSES) AND CONTROL AND ANALYTICAL LABORATORIES

Artificial lighting can be general, local or combined.

The hygienic assessment of artificial lighting includes: determining the level of illumination of the required area, characterizing the light source and fittings.

Illumination- the ratio of the luminous flux incident on a surface to the area of this surface. Express illumination in lux (lx).

Sources of light- incandescent lamps and fluorescent lamps. Their hygienic characteristics are different and are determined by the following properties of the lamps:

· the share of energy converted by the lamp into light;

· thermal radiation;

· spectral characteristics of visible radiation;

· stability of the luminous flux.

Incandescent lamps have a number of disadvantages:

· low efficiency;

· strong thermal radiation;

· a small fraction of energy converted into light - (vacuum about 7%, krypton-xenon - up to 13%);

· lamp filaments are extremely bright for the eyes;

· unlike daylight, visible radiation is dominated by yellow and red parts of the spectrum, which complicates color perception and color discrimination;

· the light flux contains almost no ultraviolet rays characteristic of sunlight.

However, a serious disadvantage of fluorescent lamps is the fluctuation of the luminous flux - stroboscopic effect. It represents multiple imaginary images of moving objects, which causes visual fatigue, distorted perception of moving objects and can cause occupational injuries. To prevent the stroboscopic effect, it is necessary to turn on several closely spaced fluorescent lamps in different phases of a three-phase electrical network.

The above differences in the hygienic assessment of light sources are taken into account when choosing them for lighting rooms for various purposes.

The brightness of the luminous surface of fluorescent lamps is insignificant, but to prevent visual fatigue, they, like incandescent lamps, are enclosed in special fittings.

Armature is a device designed to rationally redistribute the light flux, protect the eyes from excessive brightness, protect the light source from mechanical damage, and the environment from fragments in the event of possible destruction of the lamp.

An important hygienic characteristic of fittings is light distribution, i.e. distribution of illumination in space. When choosing a lamp, in addition to light distribution, the degree of protection of the light source from environmental influences is taken into account, which is especially important in damp, dusty rooms, rooms with a chemically active environment, etc.

Lamps(light sources in fittings), depending on the distribution of light, are divided into four groups:

Direct light fixtures- direct about 90% of the light onto the illuminated surface, but sharp shadows and glare may appear on them.

Lamps with predominantly reflected light- their lower spherical part is made of milk glass, and the upper part is made of frosted glass. In this case, about 65-70% of the light flux is directed to the upper part of the lamp. Such lamps are used in those rooms where diffuse lighting is required.

Indirect light fixtures- direct the entire light flux to the ceiling. Rays of light are reflected at different angles from the ceiling and the top of the walls, as a result of which shadows almost completely disappear.

Ambient light fixtures- create quite satisfactory lighting conditions: their glare is insignificant, no sharp shadows are formed on the illuminated surfaces. However, they, like reflected light lamps, absorb a significant portion of the light.

At food enterprises, natural and artificial lighting is designed in accordance with the requirements of SNiP “Natural and artificial lighting. Design standards".

Sanitary requirements for lighting of public catering establishments. Natural and artificial lighting in all production, warehouse, sanitary and administrative premises must comply with sanitary rules. In this case, natural light should be used as much as possible. Illumination indicators for industrial premises must comply with established standards.

The glazed surfaces of windows and openings, lighting fixtures and fittings must be kept clean and cleaned when dirty.

Heating hygiene

The hygienic task of heating is that it must provide a normal microclimate, a stable thermal regime that eliminates hypothermia and overheating of the body, and also facilitates compliance with technological processes.

Hygienic requirements for heating enterprises are as follows:

· heating devices must provide the temperature established by the standards, regardless of the outside temperature and the number of people in the room;

· the air temperature in the room should be uniform in both horizontal and vertical directions.

· daily temperature fluctuations should not exceed 2-3 °C with central heating and 3 °C with stove heating.

· the difference in air temperature horizontally (from windows to opposite walls) should not exceed 2 °C, vertically - 2-2.5 °C for each meter of room height;

· the temperature of the internal surfaces of the fences (walls, ceilings, floors) should approach the indoor air temperature, the temperature difference should not exceed 4-5 ° C;

· space heating must be continuous during the heating season and provide for qualitative and quantitative regulation of heat transfer;

· the heating system should not pollute the air;

· the average temperature of heating devices should not exceed 80 ° C (higher temperatures lead to excess heat radiation, burning and sublimation of dust);

· the surface of the devices must be accessible for cleaning.

There are local and central heating systems.

Local(stove) heating is characterized by low hygienic standards, because Due to the low heat capacity of furnaces, there are significant daily fluctuations in air temperature, and the premises are polluted with ash, fuel, flue gases, and dust.

Central heating is more hygienic. As a rule, it provides uniform heating of the air throughout the day. The location of heating devices under the windows prevents the formation of cold air currents near the floor. Central heating is provided by boiler houses or combined heat and power plants.

According to the type of coolant, heating systems are divided for water, steam, air, combined and panel-radiant.

Most hygienically acceptable in enterprises low pressure central water heating system. It allows you to ensure uniform air temperature in the rooms, regulate the heat supply by changing the water temperature, and eliminate the possibility of contamination of the room with dust, since the surface of the radiators usually heats up to a temperature of no more than 80 ° C.

Less hygienic steam heating. The disadvantage of steam as a coolant is the high surface temperature of the devices - not lower than 100°C, which contributes to overheating of the air and sublimation of dust. In addition, this system is difficult to operate.

Air heating usually performed with partial recirculation. Air recirculation is not allowed in rooms where the air contains industrial dust, CO 2, SO 2, substances with a pungent odor, etc.

Design heating devices for water and steam heating and their placement are of great hygienic importance, both for the heat exchange of the human body and for the general sanitary condition of the room. Heating devices are located near external fences, primarily under windows. It is recommended to use smooth heating devices. Installing finned radiators is undesirable, since the presence of fins complicates their cleaning. In rooms with significant dust emissions (flour warehouses, sugar crushing area, etc.), smooth pipes are used as heating devices.

Panel radiant heating- has a number of advantages over other heating systems: it ensures uniform heat distribution in the room, due to the presence of large heating surfaces, reduces heat transfer by radiation, and does not occupy useful space in the premises. With this system, heating elements in the form of pipes or plates with hot water or steam circulating in them, as well as hot air channels or electric coils are placed in the walls, ceiling, and floor.

With panel radiant heating, there is virtually no sublimation of dust, since convection currents in the air are extremely weak. This heating creates more comfortable conditions at an air temperature of 17-18 °C than conventional radiator systems at an air temperature of 19-20 °C. The physiological basis for this effect is that under the conditions of panel radiant heating, the human body perceives mainly radiation heat, i.e. heat from heated surfaces, which has a stronger biological effect than convection heat (heat from heated air).

The hygienic disadvantages of panel radiant heating include slow heating of the room to a given temperature and the impossibility of quickly adjusting settings.

In catering establishments all production, auxiliary premises and premises for visitors must be provided with heating in accordance with sanitary rules. Preference is given to a water heating system. In newly constructed and reconstructed enterprises, it is not permitted to install stoves that burn coal, wood, solid fuel, etc. Heating appliances should not be located next to refrigeration equipment. They should be regularly cleaned of dust and contaminants.

Ventilation hygiene

Ventilation - air exchange carried out using various systems and devices.

At food enterprises, sources of air pollution from excess heat, moisture, gaseous and mechanical impurities are production equipment, the technological process of processing raw materials and manufacturing products, etc.

With insufficient ventilation, indoor air can pose an epidemiological danger - the possibility of the spread of airborne infections increases, as well as food contamination by pathogens of foodborne infections and food poisoning.

The main purpose of ventilation is to supply a sufficient amount of clean air, remove harmful impurities, ensure appropriate microclimate indicators (temperature, humidity, etc.) and create an air-heat balance (together with heating).

With correctly calculated and rationally implemented air exchange, comfortable conditions for people to stay in the premises are created. The following ventilation systems are distinguished: natural, artificial And combined.

General hygienic requirements for ventilation of enterprises are as follows:

· ventilation devices must be provided to all rooms that require them;

· ventilation must provide all sanitary air parameters;

· all premises of enterprises must be equipped with devices that enhance natural air exchange;

· when choosing and installing artificial ventilation, the capacity of the enterprise and the purpose of individual premises should be taken into account;

· ventilation systems of individual groups of premises must be separate;

· when locating an enterprise in a building for another purpose, the entire ventilation system of the enterprise must be isolated from the ventilation of the main building;

· places where air is taken must ensure maximum compliance with hygienic standards, and places where exhaust air is discharged must ensure that there is no return flow of contaminated air into the room.

Natural ventilation is carried out due to the difference in temperature and air pressure inside and outside the room. The air exchange created as a result of infiltration through the pores of materials, the cracks of windows and doors, is unorganized and hygienically of little value.

The main hygienic importance of natural ventilation is ventilation through open window And doors. The effect of ventilation through windows is not constant and depends on the difference in air temperatures inside and outside, as well as the direction and strength of the wind. Air exchange increases with through ventilation and can reach 80-1000 volumes per hour.

To create natural, organized ventilation (aeration), arrange windows or transoms. Transoms are the most preferred. Transoms are located at the top of the window and open at an angle of 45 0 upward to the ceiling. In this case, the outside cold air is directed upward to the ceiling, where it mixes with warm air and enters the work area. This allows you to avoid drafts and colds.

To increase the intensity of exhaust ventilation, use deflectors, whose operation is based on the use of wind pressure.

Artificial ventilation. In rooms with intense air pollution from industrial hazards, only natural air exchange is not enough. Therefore, they are equipped with mechanical ventilation with forced injection of outside air and removal of contaminated air.

The artificial ventilation system is divided into: supply, exhaust, supply and exhaust, local and system air conditioning. Supply ventilation is used to supply fresh air into the premises, exhaust ventilation is used to remove polluted air. The most acceptable is supply and exhaust ventilation (general exchange), which pumps fresh, purified air into the room and simultaneously removes polluted air. Such ventilation ensures cleanliness and uniform distribution of air, and, if necessary, allows it to be heated or cooled.

The supply and exhaust ventilation system consists of air intakes, dust cleaning facilities, devices for heating or cooling air, fans with motors, air ducts with openings in rooms, and devices for purifying exhaust air.

Local ventilation. Along with general ventilation, local ventilation is widely used in food enterprises to most effectively remove excess heat, moisture, smoke, gases, etc. Ventilation devices are screens, umbrellas, curtains, ring air ducts etc. They remove 60-75% of the heat generated by the equipment from the room.

Air conditioning. A much more advanced form of artificial ventilation is air conditioning. Air conditioning systems allow you to artificially create optimal parameters of temperature, movement, humidity, air purity in a room and automatically maintain them at a given level. During the air conditioning process, the air is purified, heated in winter, and cooled and humidified in summer. In addition, air conditioners can perform air deodorization, ozonation, ionization and perfumery.

The choice of ventilation system depends on the production profile and capacity of the food enterprise. In industrial and domestic premises of enterprises, mechanical supply and exhaust ventilation is usually equipped, and in administrative premises - ventilation or air conditioning. At small food facilities, it is allowed to organize exhaust mechanical ventilation without an organized inflow.

For administrative and household, warehouse and most industrial premises, standard norms for the frequency (magnitude) of air exchange have been established. For individual production and some other premises, the amount of ventilation air exchange is determined by calculation, taking into account the amount of heat and moisture entering the given room.

The more independent ventilation systems there are in an enterprise, the shorter the length of the air ducts for each of them and the higher their reliability.

The correct equipment of mines for the intake of clean air and the emission of waste air is important for the cleanliness of air at an enterprise. Exhaust ventilation shafts must protrude at least 1 m above the roof ridge or flat roof surface.

Sanitary requirements for ventilation of public catering establishments. When using air conditioning systems, the microclimate parameters of industrial premises of public catering establishments must comply optimal values of sanitary standards, and in the presence of mechanical or natural ventilation - acceptable standards

Supply and exhaust ventilation is equipped in production, auxiliary and sanitary premises. All work associated with the formation and release of harmful substances into the air must be carried out only with the power switch on. supply and exhaust or local ventilation.

Ventilation openings should be located in such a way as to ensure maximum removal of industrial hazards, and the supply of fresh air should not cause unpleasant sensations for personnel. The location of the supply air is determined by the nature of the room and the characteristics of the production process. Thus, in the hot and confectionery shops, supply air is supplied to the working area, because The main task is to reduce heat radiation from heating surfaces. In the remaining rooms, supply air is supplied to the upper zone.

Of hygienic importance is the correct calculation of the air exchange rate per hour, as well as the ratio of supply and exhaust air, depending on the purpose of the room. In enclosed spaces, an average of 40-80 m 3 of air per hour should be exchanged.

Exhaust ventilation is planned separately for each group of premises, depending on the production hazards released in them and the required air exchange rate. Thus, separate exhaust ventilation should be in waste chambers (exhaust air exchange rate - 10 volumes per hour), in production premises, refrigerated chambers for storing fruits and herbs (4 volumes per hour). In production workshops, the exhaust should prevail over the influx (4 volumes per hour to 3, in washing rooms - 6 to 4), and in the sales area, the influx should exceed the exhaust. Under this condition, odors, excess heat and moisture will be removed from the hot shop, and fresh air will be supplied to the hall in the required quantity.

Domestic premises (toilets, shower rooms, feminine hygiene rooms) are equipped with autonomous exhaust ventilation systems, mainly with natural ventilation.

In mechanical systems supply ventilation, it is recommended to provide for cleaning the supplied outside air and heating it during the cold season of the year. Air intake for supply ventilation is carried out at a height of at least 2 m from the ground surface. The supply air supply should be in the cleanest rooms.

The temperature of the supply air should not be lower than 12 o C, and the difference in temperature between the supplied air and the room air should not exceed 5 o C (in winter, this is achieved by heating the air in air heaters); air movement speed is 0.2-1 m/s depending on thermal radiation.

In areas for finishing cream products inlet The ventilation system must have an anti-dust and bactericidal filter.

Local artificial ventilation systems. Hot and confectionery shops have significant heat emissions (250-300 kcal/m 3 /hour), therefore, in addition to general ventilation, they require a local ventilation system above the heating equipment.

The most widely used local ventilation devices are ring ducts And exhaust hoods. The area of the ventilation device should be 0.5 m larger around the perimeter than the area of the slab. A serious disadvantage of ring air exchange is its location under the ceiling at a considerable distance from the stove, as a result of which some of the released harmful substances are not captured by suction and spread throughout the room.

To improve the microclimate of hot shops, they use Suction pumps. They are installed above thermal electrical sectional modulated equipment. These suction units have not only an exhaust, but also a supply device (compartment), which ensures effective removal of harmful substances from the work area and showering workplaces with supply air jets.

Air showers are provided for thermal radiation of 300 kcal/m3/hour or more. For medium-heavy work, the air temperature during air showering in warm periods of the year should be 21-23 ° C at a movement speed of 1-2 m/s, in cold periods of the year - 17-19 ° C at a movement speed of 0.5-1 m /With.

Air showering must be used to prevent the adverse effects of infrared radiation on the body of cooks and confectioners at workplaces near ovens, stoves, ovens and other thermal equipment.

During the cold period of the year, it is recommended to equip the loading room, expedition, and lobbies thermal curtains.

Equipment and washing baths that serve as sources of increased release of moisture, heat, gases, as well as operations associated with sifting flour, powdered sugar and other bulk products must be provided local exhaust systems with preferential exhaust in the zone of maximum pollution.

Air ducts of ventilation systems are made with a minimum number of revolutions to reduce aerodynamic drag. The openings of the ventilation systems are closed with a fine-mesh polymer mesh.

Ventilation systems of the enterprise should not worsen the living conditions of people in residential buildings and buildings for other purposes. The exhaust ventilation system must be separate from the ventilation system of these buildings.