Goals of the work:
- Follow the updated requirements for air disinfection in healthcare facilities.
- Consider all types of air disinfecting devices, conduct a comparative characteristic, identifying the main positive and negative features.
- Consider and identify the difference between filters and the degree of air purification.
Introduction
Air disinfection: what has changed in the legislation
Order of the Ministry of Health No. 114n dated February 21, 2020 introduced permission for medical institutions to choose equipment for indoor air disinfection, depending on the needs of frequency classes.
Amendments were made to certain procedures for the provision of medical care in terms of complianceequipment standardsdepartments, offices and medical centers of various profiles. The new equipment selection rules came into effect in August 2020.
Previously, clinics were only allowed to use a bactericidal recirculator for air disinfection according to the requirements of Rospotrebnadzor.
Changes have come into force to allow the use of cleaners, including for filtering, decontaminating and disinfecting air (surfaces).
The changes made it possible to correlate the procedures for providing medical care and the requirements of Rospotrebnadzor for air disinfection.
Materials and Methods
Approved for use in medical institutions
After updating the order of the Ministry of Health, medical institutions can use the following equipment:
- UV irradiators;
- aerosols with disinfectants;
- bacterial filters.
This approach allows managers to focus on the tasks that health workers face, in particular, the features of the functioning of the premises and their composition, the profile of the medical organization and the established sanitary and epidemiological regime.
- Ultraviolet irradiators for disinfection of premises
Types of UV lamps:
Open (open type).
Closed (closed type) — recirculators.
Combined (can be used as open or closed). They differ in their device and method of irradiating environmental objects, so their scope is different.
OPEN TYPE IRADITORS
Sources of UV radiation in open-type devices are not covered by anything. This makes it possible to disinfect the air and all surfaces 360° from the lamp. Since ultraviolet waves propagate unhindered, people are not allowed to stay in rooms that are disinfected with an open irradiator. Since after the operation of an open irradiator, the room must be thoroughly ventilated in order to remove ozone from it as much as possible. rice. one
CLOSED TYPE IRADITORS
In these irradiators, UV rays are located inside the housing. Disinfection takes place inside the irradiator itself. Air enters there forcibly — with the help of a built-in fan. Inside the case, ozone-free bactericidal lamps are installed. Consequently, the negative impact on humans, animals and plants is completely excluded. The advantage of these irradiators is such that when they are used, they can be used in rooms where people are constantly present (which is good for the prevention of nosocomial infections both in operating rooms and in the postoperative period). Also, air disinfection can be carried out for a sufficiently long period of time, and after the procedure, mandatory ventilation of the room is not required. fig.2
- Aerosols with disinfectants, this method is based on the use of aerosol generators with disinfectants.
They allow you to evenly spray the disinfectant in the room.
- Air disinfection treatment by this method is used during general cleaning and final disinfection, the presence of people is prohibited.
- High efficiency in processing large volumes of premises, including hard-to-reach and remote places;
- simultaneous disinfection of air, indoor surfaces, ventilation and air conditioning systems;
- the possibility of choosing an adequate mode of application due to the fact that there are modes of operation of the generator — dispersion, duration of processing cycles, consumption rates, particle energy;
— also the economy of this type (low consumption rate and reduced labor costs);
The efficiency of treatment depends not only on the characteristics of the aerosol generator itself, but also on the disinfectant that is placed in it.
You also need to check whether the equipment that is in the room and the interior wall decoration is compatible with the disinfectant used.
Some generator aerosols contain substances that can corrode materials. Such disinfectants will effectively perform their main task of cleaning the environment, but due to the ingress of aerosol particles, some equipment and coatings can quickly become unusable.
- Bacterial and electrical filters.
Bacterial and electrical filters are used for air disinfection in rooms of cleanliness classes A and B, devices that exhibit high efficiency are used:
Premises of cleanliness class A with inactivation of microorganisms at the outlet of the device by at least 99%
Premises of cleanliness class B with inactivation of microorganisms at the outlet of the device by at least 95%
Filtration is carried out according to high efficiency filters (H11-H14).
Some medical facilities also use quartz irradiators to disinfect the room.
General characteristics of air filters
Air filters are divided into classes according to the degree of purification: — Air purification filters for general purposes. — Highly efficient EPA, HEPA and ULPA air purification filters
Air filter types
- Coarse filters
They purify the air from large particles: sand, dust, fluff, pet hair. They are divided into 4 classes: G1, G2, G3, G4 according to GOST and EU1, EU2, EU3, EU4 according to the European standard. The higher the class, the more dust they trap: from 60 to 90%.
- Fine filters
Purify the air from fine dust, plant pollen, mold, fungal spores. They are divided into 5 classes: F5, F6, F7, F8, F9 according to GOST and EU5, EU6, EU7, EU8, EU9 according to the European standard. The higher the class, the more dust they hold: from 80 to 95%.
- High Efficiency HEPA Filters
Purify the air from the smallest dust, allergens, viruses, bacteria and unpleasant odors. They are divided into 5 classes: H10, H11, H12, H13 and H14 according to GOST and the European standard. The higher the class, the more dust is retained by the HEPA filter: from 85 to 99.5%.
- ULPA Ultra High Efficiency Filters
They purify the air like HEPA filters, but they can retain even less polluting particles: dangerous microorganisms, radioactive particles. ULPA filters are divided into 3 classes: U15, U16, U17. The higher the class, the more pollutants they trap: from 99 to 99.9%.
More about HEPA filters
HEPA is an abbreviation for High Efficiency Particulate Arresting, translated into Russian means highly effective particle retention. HEPA air filters are mainly used in ventilation equipment. rice. four.
A HEPA filter consists of a metal or plastic housing and filter material folded like an accordion. The thickness of the filter fibers from 0.5 to 5 microns (µm) is less than 1/10 of the thickness of a human hair. The distance between them is from 5 to 50 microns. The fan pushes air through the filter and contaminants get stuck between the fibers, like in a sieve.
HEPA — the filter can detain particles from 0,3 microns. Scientists have proven that the most dangerous particles up to 2.5 microns in size are fine dust. WHO has included it in the list of the most dangerous air pollutants.
The HEPA filter needs to be changed — manufacturers recommend 1-2 times a year so that its efficiency does not decrease.
Difference between HEPA filter classes
According to the international HEPA classification — filters are divided into 5 classes. The higher the class, the more polluting particles they trap. Comparative characteristics of HEPA filters:
HEPA filter class | Cleaning efficiency |
H10 | at least 85% |
H11 | at least 95% |
H12 | not less than 99.5% |
H13 | at least 99.95% |
H14 | not less than 99.995% |
HEPA — class H12 and H13 filters can be used in the surgeon’s office, in the electronics industry and in the nuclear industry to prevent radioactive particles from entering the atmosphere. The H14 HEPA filter is not used for air purification because it is difficult to operate.
In ventilation equipment, the air passes through several filters. For example, a breather is a device that supplies and purifies air from the street. It passes air through coarse and fine filters and only then through a HEPA filter. rice. 5
Most Airborne Particulates: Methods for Reducing Nosocomial Infections in the Operating Room. Modern methods of air disinfection in surgical hospitals.
Discussion
Used in hospitals to purify the air
All types of hospitals and clinics must be equipped with a modern ventilation and air conditioning system. For them, increased requirements are provided for maintaining certain sanitary standards of the microclimate, creating an isolated airspace in individual rooms and eliminating the likelihood of air from getting from dirty areas to clean ones.
Operating rooms require special sanitary conditions, which can be achieved by installing laminar ceilings with HEPA filters with H14 cleaning class. To improve the air exchange rate and reduce contamination, it is recommended to use autonomous recirculators equipped with a filtration class of H11 and higher.
To remove dangerous microorganisms, dust particles, allergens and other pathogenic particles, air conditioners in medical facilities have a reliable fine and coarse filtration system. For this purpose, carbon, catechin, photocatalytic and UV filters are used.
For bactericidal air treatment, FBO filters are optimally suited, capable of performing deep purification of air flows using UV rays. Such devices are produced with different radiation power and can be used in rooms of different categories., animal hair and dander, dust mites — no larger than 0.001 mm — HEPA filters of all classes cope with them.
In the recirculation mode, the ventilation equipment filters the air inside the enclosed space — with each cycle of operation, dust settles on the filter, respectively, the air becomes cleaner. The efficiency of the device is affected by performance: the more air passes through the filter in one working cycle, the greater the cleaning efficiency.
Results:
- The new requirements for air disinfection in healthcare facilities allow the use of air disinfection devices: UV irradiators, aerosols with disinfectants, bacterial filters.
- Medical institutions use: UV — irradiators: open and closed type, aerosol generators with disinfectants, bacterial filters 1. Coarse filters. 2. Fine filters. 3. High efficiency HEPA filters. 4. Ultra High Efficiency ULPA Filters.
- According to the international HEPA classification — filters are divided into 5 classes. The difference between filters and the degree of purification depends on the fact that the higher the class, the more polluting particles they trap.
References
1. https://melitta-uv.ru/apply/areas/khirurgiya/2. https://www.zdrav.ru/
3. https://air-vent.pro/blog/bakteritsidnaya-obrabotka-pomeshcheniy/filtry-dlya-meditsinskikh-uchrezhdeniy/