Target:
Conditions: quartzing during current cleaning is carried out for 30 minutes, with spring cleaning-2 hours.
Indications:
Equipment:
gloves;
disinfectant solution;
alcohol 70%;
cotton swab, rags.
bactericidal lamp OBN;
workwear;
Execution order:
The device is designed for disinfecting indoor air.
Before connecting the device to the network, make sure that the power cord is not damaged.
Plug in the power cord for a certain period of time (for current cleaning for 30 minutes, for general cleaning for 2 hours).
It is forbidden to enter the room when the bactericidal lamp is turned on; entry is allowed 30 minutes after the lamp is turned off and aired.
The bactericidal lamp is replaced after 8000 hours of operation.
The operation of the bactericidal lamp is recorded in the Quartz Treatment Logbook.
The external finishing of the device allows for wet sanitization with a 0.1% Javel-Solid solution (solichlor, deochlor), twice with an interval of 15 minutes. Wipe the bactericidal lamp with a moistened gauze swab ethyl alcohol, once a week.
Sanitation and cleaning of the device is carried out after disconnecting from the network.
Do not allow liquid to get inside the bactericidal lamp!
Unshielded mobile bactericidal irradiators are installed at a power rate of 2.0 - 2.5 watts (hereinafter referred to as W) per cubic meter (hereinafter referred to as m3) of room.
Shielded bactericidal irradiators with a power of 1.0 W per 1 m3 of room are installed at a height of 1.8 - 2.0 m from the floor, provided that the radiation is not directed towards people in the room.
In rooms with intense continuous load, ultraviolet recirculators are installed.
Troubleshooting the germicidal lamp is carried out by a medical equipment maintenance engineer.
Germicidal lamps belong to class “G” according to the unified classification of medical waste. Collection and temporary storage of used lamps is carried out in a separate room.
9.3 Algorithm “Carrying out routine cleaning in a hospital, clinic, laboratory, laundry, catering unit and temporary storage warehouse for medical waste of class “b” and “c””
Target: prevention of nosocomial infection.
Conditions: carrying out routine cleaning.
Indications: control of nosocomial infections.
Equipment:
disinfectants and detergents;
bactericidal lamp or recirculator.
cleaning equipment, rags;
measuring containers;
workwear;
safety shoes;
gloves;
Execution order:
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Event. |
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In the operating unit, in the department of anesthesiology, resuscitation, intensive care, in the sterile blocks of the central sterilization department and bacteriological laboratory, in the section room and in the laboratory of the pathology department current wet cleaning carried out 2 times a day using disinfectants (solution concentration as during general cleaning): 0.1% Javel-Solid = 7 tablets per 10 liters of water or 0.1% deochlor = 7 tablets, 0.1% Soliclor=7 tablets, 1.0% aldazan=80 ml to 8 liters of water, 2.5% defect = 250 ml to 10 liters of water, 2.0% dolbak = 200 ml to 10 l of water, 0.2% lysorine = 20 ml to 10 liters of water, 0.2% dezosept = 20 ml to 10 liters of water, 0.1% septalite=10 ml to 10 liters of water, 0.032% septalite DCC = 2 tablets per 10 liters of water. |
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Routine wet cleaning is carried out in other rooms, wards, offices, laundry and in the catering department of the branch carried out 2 times a day using disinfectants in a concentration of 1 tablet per 10 liters of water. |
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Wet cleaning of all surfaces is carried out: window sill, bed, bedside table, cabinets, tables, floor, doors, door handles, sinks and taps, water and sewer pipes. |
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Quartzization of a room or office with a bactericidal lamp or recirculator for 30 minutes. Hang a sign on the door “Attention, the bactericidal irradiator is on!”; Record the time in the quartzing log and in the general cleaning log. |
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Ventilate the room for 15-30 minutes depending on the season. |
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IN summer period, from June 1 to September 1 annually, the concentration of the working solution is increased disinfectant(for example: 2 Soliclor tablets per 10 liters of water) to prevent intestinal infections. |
The disinfection mode depends on the power of the irradiator, the volume of the room, the criteria for the effectiveness of disinfection, determined functional purpose premises, and is determined in accordance with the “Guidelines for the use bactericidal lamps for disinfection of air and surfaces”, approved by the Ministry of Health and Medical Industry of the Russian Federation on February 28, 1995.
Open (unshielded) bactericidal lamps are used only in the absence of people, during breaks between work, at night, or at specially designated times - for example, 1-2 hours before the start of aseptic work. The minimum irradiation time is 15-20 minutes.
Switches for open lamps should be placed in front of the entrance to the room and equipped with a warning sign “Do not enter, the bactericidal irradiator is on.” It is PROHIBITED for people to be in rooms where unshielded lamps are switched on. Entry into the room is permitted only after the lamp is turned off, and a long stay in the specified room is allowed 15 minutes after the lamp is turned off.
Shielded germicidal lamps can operate up to 8 hours a day. It is more rational to carry out irradiation 3-4 times a day for 1.5-2 hours with breaks to ventilate the room for 30-60 minutes, since when the lamp operates, ozone and nitrogen oxides are formed, causing irritation of the mucous membrane of the respiratory tract. IN last years ozone-free bactericidal lamps have been created, which is achieved through the use of special quartz glass that does not transmit UV radiation shorter than 200 nm, which causes the formation of ozone.
Air irradiation with PRK lamps is carried out for 30 minutes several times a day at intervals used to ventilate the room.
It is necessary to take into account the operating time of each irradiator in a special journal, recording the time the lamp is turned on and off. It is prohibited to use germicidal lamps with expired suitability. The average service life of the BUV bactericidal lamp is 1500 hours, PRK lamps – 800 hours.
Strict adherence to the use of bactericidal lamps is important, since the boundary between the conditions for the positive bactericidal effect of UV irradiation and the negative one associated with the selection of resistant microflora under weak exposure to UV rays is not clear enough.
UV rays are effective at a distance of no more than 2 meters and at relative humidity air from 40 to 70%, with more high humidity their bactericidal effect is reduced. On dark surfaces treated with UV rays, 10–20% more microbes remain than on light surfaces under the same conditions. In the shade, for example, under a table board or on back side tool, ultraviolet radiation has no effect.
Errors leading to negative epidemiological consequences include:
Failure to comply with prescribed radiation regimes;
Inconsistency of the type (open, closed) and number of irradiators with the needs of premises sanitation;
Not taking into account the “age” of the lamps, as it increases, their bactericidal activity significantly decreases;
Surface contamination of lamps;
- “exaggerated expectations” for the effectiveness of ultraviolet irradiators, which contributes to the neglect of other, no less reliable methods of sanitizing premises - ventilation, cleaning, treatment with chemical disinfectants, increasing the efficiency of ventilation.
To assess the bactericidal effectiveness of specific irradiators, a bacteriological study of air and surface washes is carried out before and after irradiation. Sanitation is considered effective if, after irradiation, the number of microorganisms in 1 m³ of air has decreased by 80% or more.
Questions for self-control
1. What pathogens can spread through the air, aerogenously?
2. Which phase of microbial aerosol is the most dangerous epidemiologically?
3. What can be a source of microorganism pollution in the air of pharmacies?
4. The main factors in the transmission of pathogens from a sick person to a healthy person or to a drug.
5. Standards for microbial air pollution in pharmacy premises.
6. Modern methods Air Bacterial Research.
7. Which area of ultraviolet radiation has a bactericidal effect?
8. What is the mechanism of bactericidal action ultraviolet rays?
9. In what areas of the pharmacy should bactericidal irradiators be installed?
11. What bactericidal lamps can be turned on in the presence of people?
12. What is the average service life of a BUV type bactericidal lamp?
1. General Provisions.
1.1. The main task of the calculation is to determine, when performing a technical project, the number of irradiators () of an ultraviolet bactericidal installation that should be placed in the room, or lamps () in the exit chamber supply and exhaust ventilation in order to ensure a given level of bactericidal effectiveness.
1.2. It should be noted that the calculation is an estimate, therefore, at the stage of putting the ultraviolet bactericidal installation into operation, adjustments to the calculation results are allowed based on the data obtained when testing for compliance with the requirements of sanitary and hygienic indicators, in accordance with this manual.
1.3. To carry out the calculation, it is necessary to determine the initial data. First of all, the sources for obtaining initial data are: medical and technical specifications for the design of an ultraviolet bactericidal installation, passports and instructions for bactericidal irradiators and lamps, as well as this manual.
1.4. The main initial data for the calculation are as follows.
1.4.2. Room dimensions (height h, m, floor area S, m 2).
1.4.3. Type of microorganism.
1.4.4. Bactericidal effectiveness (, %) and surface (, J/m 2) or volumetric (, J/m 3) dose (exposure) corresponding to the type of microorganism.
1.4.5. Type of bactericidal installation.
1.4.6. Supply and exhaust ventilation capacity (, m 3 / h).
1.4.7. Conditions for disinfection (in the presence or absence of people).
1.4.8. Object of disinfection (air or surface).
1.4.9. Irradiation mode (continuous or intermittent).
1.4.10. Duration of effective irradiation ( , h), at which the achievement of a given level of bactericidal effectiveness should be ensured.
1.4.11. Type of irradiator, lamp and their parameters: efficiency (), coefficient of utilization of bactericidal flux (), total bactericidal flux of lamps (, W), bactericidal flux of lamp (, W), bactericidal irradiation at a distance of 1 m from the irradiator (, W/m2 ), irradiator power ( , W).
1.5. The obtained initial data allows you to determine the number of irradiators in the room or lamps (in the output chamber of the supply and exhaust ventilation) of the bactericidal installation, depending on the task, using the equations given in this manual.
1.6. Examples of calculation of bactericidal installations.
Example 1. It is necessary to determine the number of open irradiators of the OBB 2×15 type in a bactericidal installation for air disinfection in the operating room in the absence of people. The initial data required for the calculation are summarized in a table.
| Designation | Parameter value | A source of information | |
| Room dimensions | h, m | Medical and technical building | |
| S, m 2 | |||
| Type of microorganism | S. aureus | - | -"- |
| Room category | I | - | Section 5, table. 3 |
| Bactericidal effectiveness | , % | 99,9 | -"- |
| Volume dose | , J/m 3 | -"- | |
| Germicidal lamp flow | , W | 4,5 | Passport for the irradiator |
| Number of lamps in the irradiator | -"- | ||
| 0,8 | Section 6 | ||
| Safety factor* | 1,1 | -"- | |
| Irradiation mode | Repeatedly short-term | - | Section 7 |
| , h | 0,25 | -"- |
Using the given data, using formula (9) we determine required number irradiators OBB 2×15 for air disinfection in the operating room:
Example 2. It is necessary to determine the number of closed irradiators (recirculators) type OBN (P) 2×15 in a bactericidal installation for air disinfection in the operating room in the presence of people. The initial data required for the calculation are summarized in a table.
Table of initial data for calculation
| Name and characteristics of the parameter | Designation | Parameter value | A source of information |
| Room dimensions | h, m | Medical and technical building | |
| S, m 2 | |||
| Type of microorganism | S. aureus | - | -"- |
| Room category | I | - | Section 5, table. 3 |
| Bactericidal effectiveness | , % | 99,9 | -"- |
| Volume dose | , J/m 3 | -"- | |
| Germicidal lamp flow | , W | 3,5 | Passport for the irradiator |
| Number of lamps in the irradiator | -"- | ||
| Bactericidal flow utilization rate | 0,4 | Section 6 | |
| Safety factor* | 1,5 | -"- | |
| Irradiation mode | Repeatedly short-term | - | Section 7 |
| Duration of effective irradiation at which a given bactericidal effectiveness is achieved | , h | -"- |
Using the given data, using formula (9) we determine the required number OBN irradiators(P) 2×15 for air disinfection in the presence of people in the operating room:
Example 3. It is necessary to determine the number of open ceiling irradiators of type OBNP 2×15-01 "VNIIMP-VITA" in a bactericidal installation for disinfecting the floor surface in the operating room in the absence of people. The initial data required for the calculation are summarized in a table.
Table of initial data for calculation
| Name and characteristics of the parameter | Designation | Parameter value | A source of information |
| Room dimensions | h, m | Medical and technical building | |
| S, m 2 | |||
| Type of microorganism | S. aureus | - | -"- |
| Room category | I | - | Section 5, table. 3 |
| Bactericidal effectiveness | , % | 99,9 | -"- |
| Volume dose | , J/m 3 | -"- | |
| Germicidal lamp flow | , W | Passport for the irradiator | |
| Number of lamps in the irradiator | -"- | ||
| Bactericidal flow utilization rate | 0,7 | Section 6 | |
| Safety factor* | -"- | ||
| Irradiation mode | Repeatedly short-term | - | Section 7 |
| Duration of effective irradiation at which a given bactericidal effectiveness is achieved | , h | 0,25 | -"- |
Using the given data, using formula (6) we determine the required number of OBNP 2×15-01 "VNIIMP-VITA" irradiators for disinfecting the floor in the operating room in the absence of people:
In this formula:
coefficient of utilization of the flux of irradiator lamps when irradiating a surface (from Table 2, according to the value of the room index).
Hence:
Example 4. It is necessary to determine the type of unit with DBM 30 bactericidal lamps in the supply and exhaust ventilation outlet chamber in the trauma department ward. The initial data required for the calculation are summarized in a table.
Source data table
| Name and characteristics of the parameter | Designation | Parameter value | A source of information |
| Room dimensions | h, m | Medical and technical building | |
| S, m 2 | |||
| Type of microorganism | S. aureus | - | -"- |
| Room category | I | Section 5, table. 3 | |
| Bactericidal effectiveness | , % | - | -"- |
| Volume dose | , J/m 3 | -"- | |
| Germicidal lamp flow | , W | Passport for the irradiator | |
| Number of lamps in the irradiator | -"- | ||
| Bactericidal flow utilization rate | 0,9 | Section 6 | |
| Safety factor* | 1,5 | -"- | |
| Irradiation mode | Repeatedly short-term | - | Section 7 |
| Duration of effective irradiation at which a given bactericidal effectiveness is achieved | , h | ≤ 1 | -"- |
* The safety factor during calculations is set depending on the presence of factors influencing the decrease in efficiency (fluctuations in network voltage, temperature changes environment, increase in relative humidity more than 80%, high dust content in the air). At a stable voltage in the network, room temperature, relative humidity up to 70% and dust content less than 1 mg/m 3 these factors can be neglected (section 6.3)
Using the given data, using formula (11) we determine the required number of lamps in the block:
In this formula, the productivity of supply and exhaust ventilation is m 3 / h. In this case, the duration of effective irradiation at which the specified bactericidal effectiveness is achieved (see section 7).
Consequently, of the existing units, the one that most satisfies the requirements is a unit of type UBPV-12×30 - 300×400 with 12 DBM 30 lamps.
They constantly live in the air various microorganisms who are carriers of infections and viruses. It is unrealistic to fight germs and bacteria outdoors in an open space. But it is possible to purify the indoor air using special devices.
If a person has high immune defense, his body independently fights pathogenic microorganisms. However, people with weak immune systems are much more likely to catch diseases carried by bacteria and viruses. For this reason, bactericidal lamps are widely used in medical institutions, schools, kindergartens, and catering establishments.
Scope and purposes of operation
The bactericidal irradiator became effective means in the fight against infectious diseases, viruses and many other pathogenic agents, especially in the cold season.
The lamps do an excellent job of disinfecting air, surfaces and water. Open bactericidal irradiators are used only where people and other living beings are not present. And closed lamps are successfully used in rooms where people and other living beings are located. Maximum effect in air purification and disinfection demonstrates the use of two types of mercury-quartz devices.
UV disinfection lamps are suitable for:
- Air purification.
- Disinfection of rooms, certain items, tools and equipment.
- Water disinfection.
- Disinfection of cutlery and dishes.
- General improvement of the microclimate.
Operating Requirements
Depending on the nature of the actions performed and the purpose of the premises, they are classified into three categories:
- Rooms where disinfection is carried out in the presence of a person.
- Rooms where the air is disinfected in the absence of living beings.
- Premises where disinfection is carried out in the short-term presence of a person.
To disinfect rooms with the constant presence of living beings, it is necessary to use closed-type devices that do not allow direct radiation to escape into the room. Recirculators are used for this. With their help, continuous operation of the lamp is ensured.
If it is possible to temporarily vacate a room from people, then bactericidal irradiators are used that carry out disinfection with a directed ultraviolet stream. Such devices do not work for long.
Short-term exposure to ultraviolet light provides children with vitamin D, usually supplied by sunlight. "Sunshine Vitamin" strengthens young bones. Recirculators are installed in rooms on the walls, taking into account the main air flows, namely next to heating devices at a height of 2 meters from the floor.
If the room is cleared of people for a short time, then mixed-type irradiators become appropriate. While there are people in the room, they work, and when the room remains empty, the irradiators are turned on a short time. In this case, the operating time of the device is reduced to 5 minutes. The intervals between disinfections are 3 hours. Thanks to mixed disinfection devices, the degree of disinfection of rooms during preparation for operations increases.
In the absence of a person, disinfection is carried out with open instruments or devices combined type. The maximum duration of irradiation is 25 minutes. During this time, the required level of bactericidal effect is achieved. The intervals between services should be at least 2 hours.
Power supply for ultraviolet installations open view supplied using special switches located outside the room, next to the entrance. These switches are accompanied by the use of an illuminated sign indicating “Danger” or “Do not enter, disinfection in progress.”
Expert opinion
Alexey Bartosh
Ask a question to an expertAttention! To prevent unexpected exposure of people to ultraviolet radiation, devices are recommended that block the power supply to the device if the doors are opened.
Switches for “ozone-free” devices are mounted in any accessible place. Above them you need to hang a sign “Bactericidal irradiation”.
It is imperative to provide personal protective equipment for employees from ultraviolet radiation: face masks, glasses, gloves. These things are used when there is an urgent need for a person to be in the room when the irradiator is operating.
Glasses - means of protection against negative impact bactericidal and quartz lamps Operation of open ultraviolet lamps in a room where there are people is strictly prohibited, according to sanitary rules.
When using irradiation devices mixed type the bactericidal flow from the shielded lamp is directed to the ceiling in such a way as to prevent the rays from reaching living objects.
Combination devices are equipped with separate switches, which provide separate control of the unprotected and shielded bulbs. In this case, the action of open lamps is permissible only in the absence of living beings in the room.
Using mobile types of irradiators for effective disinfection, service personnel wear face masks, protective gloves and goggles. These products prevent ultraviolet rays from reaching the skin and mucous membranes of the eyes. Disinfection is carried out without the presence of strangers.
Installations that use reflected flow in their operation are used exclusively in places where people are present for a short time, for example, in warehouses, toilets, corridors. It is important to observe hygienic requirements by degree of exposure, duration of single exposure and time interval between procedures and total time action of the irradiator.
Regardless of the purpose of the room and under any conditions, bactericidal devices are placed in such a way as to prevent human exposure to direct directed ultraviolet radiation.
How to improve efficiency?
To increase the operating efficiency of bactericidal devices, following rules. Closed irradiators or recirculators are installed in rooms on the walls in the same direction as the main air flows, at a height of 2 meters from the floor surface. If several lamps are used, they are placed around the perimeter at the same distance from each other.
Germicidal lamps are placed in places where people frequent The effectiveness of ultraviolet treatment of a room is assessed by the reduction in the concentration of bacteria in the air, on the surfaces of furniture, walls and equipment under the influence of ultraviolet radiation. The basis is an assessment of the degree of microbial contamination before irradiation and after the procedure. Both values are compared with standards.
One of the distinctive qualities of bactericidal devices is the high dependence of their emitting and electrical characteristics from fluctuations in electrical voltage. When the mains voltage increases, the life of the lamps decreases. When the tension increases by 20 percent, the operating time drops to 50 percent. If the voltage drops by more than 20 percent, the germicidal lamps burn unsteadily or go out completely.
During lamp operation, the emitted ultraviolet flux gradually decreases. A too rapid reduction in flux is observed during the first tens of hours of using the lamp - up to 10 percent. With further use, the rate of reduction decreases. The duration of lamp operation is affected by the number of switches.
Indoor air temperature and movement air masses reflected in the fluxes of lamp radiation. Closed devices practically do not change their power when external temperatures change, unlike open lamps. The lower the room temperature, the more difficult it is to ignite devices, the sputtering of electrodes increases, which reduces the service life of the product. If the air in the room is colder than 10 degrees Celsius, some lamps may not turn on.
The electrical characteristics of bactericidal devices practically do not differ from the parameters of standard ones fluorescent lamps. They can be connected to the network alternating current.
Service
- The flasks of bactericidal lamps, as well as the screens used, must be cleaned from dust. These procedures are carried out according to a set schedule.
- Dust is wiped only on devices that are disconnected from power.
- Lamps whose operational period, indicated in the documents, has ended, must be replaced with new ones in a timely manner. To determine the expiration date, electric meters are used that show the total operating time of devices in hours. The readings of radiometers confirming a decrease in the power of antibacterial radiation are also taken into account.
The bactericidal lamp instructions for use describe all the requirements regarding safety and rules of interaction with the device. Before turning on the device, you need to carefully set right direction radiation flux. It is also necessary to strictly follow safety instructions when using stabilizers.
Cleaning and processing of the device is carried out only after it is disconnected from the power supply. These procedures are performed with soft sponges without water. In treatment rooms, kindergartens, and clinics, there is always a logbook where the operation of these devices is recorded.
Safety requirements
When ultraviolet waves up to 320 nm hit open skin or dangerous burns to the eyes and a serious risk of developing melanoma, a skin cancer. Therefore, disinfection lamps are used at a time when there is no one in the room. In some cases, it is acceptable for an adult to be in the room, but the lamps must be protected by an opaque reflective screen that directs the emitted flux towards the ceiling. Remember that no rays from the lamp should reach the area in which living beings, including people, are located.
It is prohibited to use lamps that are not equipped with screens if they are in a person’s field of vision.
Each irradiator has accompanying documents that describe technical properties, types of lamps, magnitude and intensity of flux, expiration dates and production date.
In any disinfection devices, disinfectant lamps and irradiator elements must be kept perfectly clean, since even a slight layer of dust becomes an obstacle to the flow of radiation.
Thanks to the study of methodological recommendations, the user high level will comply with the requirements of current regulations describing sanitary standards maintenance of various children's, medical, home premises or production workshops, equipped with irradiators with bactericidal lamps.
When using the described disinfection devices, it is taken into account that ultraviolet irradiation is not a replacement for standard sanitary and epidemiological measures, but only a supplement to them in the form of the final stage of space treatment.
In case of contact with skin or mucous membranes, bactericidal streams from lamps lead to burns. Therefore, it is possible to use bactericidal lamps only in an empty room where there is nothing living. In some situations, a person may be in the room during disinfection. But at the same time, the lamp is equipped with a reflector that directs the flow of ultraviolet radiation upward. The use of unshielded devices near people is prohibited. After performing the procedure, the room needs to be ventilated, especially if a person hears the sour aroma of ozone.
After use, mobile irradiators are sent to a special storage room and covered with covers.
Lamps that have burned out the allotted number of hours are subject to mandatory replacement. The reason for replacement is also a reduction in the llama flow if its indicator is below the limit. This value is determined by metrological control.
If the lamp is broken or damaged, do not allow mercury vapor or mercury itself to enter the room.
It is prohibited to throw away both whole used lamps and broken devices into general waste containers. These products are sent to the appropriate regional centers involved in the processing of mercury-containing devices. If mercury does get into the room, demercurization is mandatory.
Expert opinion
Alexey Bartosh
Specialist in repair and maintenance of electrical equipment and industrial electronics.
Ask a question to an expertAttention! During operation of the irradiator, ozone may form inside the room. This substance is dangerous to human health. TO negative influence Children and people with disabilities are especially sensitive to ozone. chronic diseases respiratory tract. Therefore, regular monitoring of the ozone content in the air of the treated room is required. Concentrations exceeding the norm are unacceptable.
To reduce the risk of ozone formation, preference is now given to ozone-free lamps - closed devices covered with uviol glass rather than quartz. A quartz lamps may only be used in a room free of living creatures.
Disinfection of catering premises
Organizations in the catering sector, such as cafes, canteens, kitchens and restaurants, are considered to be at high risk for the occurrence of outbreaks and the rapid spread of infectious diseases. Consequently, these establishments are closely monitored by the relevant authorities.
As a rule, disinfection in canteens and restaurants is carried out for prevention. This procedure includes not only mechanical cleaning, but also disinfection using bactericidal lamps.
Disinfection of kitchens in catering establishments is also important. They are carried out to prevent food spoilage and contamination by pathogenic microorganisms. Therefore, bactericidal lamps are now widely used in hot and cold cooking shops. Such lamps study ultraviolet radiation, which destroys bacteria in the air and on indoor surfaces. Ultraviolet irradiators can be used not only to disinfect space, but also to disinfect equipment, kitchen equipment, containers and devices.