How to disinfect an air duct in ventilation- Overview and Types and instructions + Video

How to disinfect an air duct in ventilation- Overview and Types and instructions + Video Disinfection of air ducts of ventilation systems. It is impossible that dirt, dust and so on do not get into the room, but exactly 40% gets inside through the ventilation system, if you do not carry out regular cleaning. Because of this, it was decided to conduct a survey and find out if people are aware of the fact that the system needs to be cleaned and disinfected.

But the poll struck: of the total number of people who order the installation of ventilation, only 1/10 of the respondents order disinfection of the air ducts of the system. This terrible statistic does not make anyone happy, since ventilation pollution has already entered the list of public problems, while the public itself is not in the know.

When installing a ventilation system in a room, there is still no lifetime guarantee that henceforth you will always have clean air. How often do you think about this procedure? Did you know that a lot of dust, dampness and bacteria enter a room from dirty ventilation if you do not clean it? And how often should you do it? It is advisable to find out about this during installation so as not to be idle, otherwise in the future, dirty ventilation will only bring harm. It is not for nothing that they say that "ignorance does not absolve one from responsibility."

General questions

How often should the air ducts be disinfected?

According to microclimate parameters and air exchange rates, which regulate the optimal temperature regime, the speed of air movement and humidity, the frequency of the procedure is determined, while all the norms are included in the sanitary (SNiP) and state-building (DBN) rules.

According to them, the quality of ventilation should be regularly checked at least once a year, and at the same time, the air ducts of the ventilation system should be disinfected.

Yes, that it is necessary to carry out cleaning at least once a year is written in V. 2. 5-20 DBN, and SNiP states that maintenance of the systems should be observed at the frequency indicated in the instructions for using the device.

But in any case, air systems and air ducts must ensure good air passage at least within the established standards, and every hour the entire volume of air must change. This will not be possible in case of heavy pollution, since the amount of fresh air will gradually decrease due to the layer of dirt.

What is cleaning for?

After some time, a layer of dust, external debris, mud deposits, grease or industrial pollution will be deposited in a thick layer on the ventilation ducts. This, in turn, leads to the development and dispersal of bacteria, pathogenic microbes, mites and insects, which is unacceptable, especially when it comes to living quarters. Through clogged channels in mechanical ventilation systems, germs and viruses can spread throughout all rooms, and this affects the well-being of people and their performance.It is worth noting that due to dustiness in the channels, the risk of ignition and fire spread immediately increases, even despite the presence of special valves that retard the fire in case of danger.

The most common problem is the rebuilding of the partition by neighbors who, for the sake of their comfort, can easily "brick up" the ventilation duct.

The ventilation may also be blocked due to the fact that part of the exhaust duct has collapsed, or a brick has got into the exhaust shaft. Traction may disappear completely after the reconstruction of the building. In this case, the specialists you have called will first check the traction parameters, and then they will eliminate the damage and, if necessary, install the supply or exhaust devices of the required performance.

In every supply and exhaust ventilation system, and especially in educational / children's / technological institutions, there is a strictly regulated service for the disinfection of ventilation systems ducts. Each such system must be serviced on time, depending on its type, according to all sanitary standards.

Such cleaning works are carried out once every 4-6 months (and sometimes annually), depending on the degree of pollution, load, operating mode and operating conditions of the forced ventilation device.

Please note, that systems with natural ventilation must be serviced at least once every 3 years, and with mechanical ventilation at least once a year. When it comes to operation in hazardous conditions, then once a month.

Types of contamination

The ventilation system can be contaminated for various reasons, and this will determine how to clean this or that system, and what means to use ..


The most common cases are described here:

  • How to disinfect an air duct in ventilation- Overview and Types and instructions + Video Dirt with streets / nearby premises and ordinary dust that safely settles on the filter or in the duct.
  • Fungus and mold, as well as water deposits, which form when moist air moves in the duct, or when condensation forms inside due to sudden temperature changes.
  • Rust deposits also occur due to moisture, and after some time can lead all equipment and air ducts to failure or the appearance of cracks, which is also unacceptable.
  • Fat deposits that greatly forget ventilation, check valves, filters, and because of this, the system performance decreases.

    Most often this occurs in residential buildings in the kitchen / restaurant, and requires regular cleaning, and more often than once a year. In this case, special attention is paid to grease traps, exactly once 1 month.

  • Deposits in the reagent and chemical system can be found in chemistry classrooms, laboratories and research centers. It is very important to neutralize all harmful substances and components, since otherwise a person's stay in such a room endangers his health.
  • It is especially important to maintain buildings of medical institutions on an ongoing basis, and as for the disinfection of air ducts in ventilation, at least once every six months.

    The fact is that this place is the largest in terms of the number of bacteria, and for this reason the hood must work at full capacity, and this is difficult to achieve in case of contamination. In addition, if sanitary standards are not observed, there can be no talk of sterility, if bacteria stagnate in the wards, dirt and dust constantly flies from the ventilation.

  • Pollution after flood and fire. This is a separate topic, since cleaning in this case is carried out unexpectedly and irregularly, but it is urgent. The fact is that during a fire, all clots of smoke and deposits will accumulate at a tremendous speed in the duct, and even after repairs you will breathe chemically harmful substances and fumes, which is not very good.

    And during a flood, a large amount of humid air flows through the duct, and at the same time, a huge amount of condensation forms. This can lead first to the formation of fungus in the system, and then in the living quarters, and you will not even be able to understand where this came from, since the flooding was long ago.

Common mistakes and consequences

Yes, if you do not disinfect the duct and clean it, it will not give the best result. How to prevent this? Let's take a look at the most common mistakes.

Error # 1.

As you may have guessed, this is to completely abandon the cleaning of the ventilation system. This will lead to massive reproduction of microbes, the appearance of a large amount of dirt. The degree of pollution depends on the general pollution in the room.

Error # 2. You have decided to do all the work yourself.

The impulse is good, but it is better to refuse it. Usually, a person removes the tip of the iceberg during self-cleaning, or only cleans the equipment, when this is not enough. Cleaning should be carried out completely, since at startup, what is left inside will still enter the room.

Error # 3. Untimely filter cleaning / replacement.

It should be remembered that filters accumulate on themselves most of all contaminants, and when they are very forgotten, they either stop letting in the required amount of air, or the air flow breaks through the filter and all that dirt that has accumulated for so long flies towards you.

Error # 4. Cleaning without disinfection of air ducts of ventilation systems. If you remove only a layer of dirt, then of course it will be cleaner, but without disinfection, germs and harmful organisms will remain in the filters and air duct. It is very important to carry out this procedure using special means to eliminate all allergens, germs, grease, chemical components, etc.

, which can lead to a deterioration in human health.

Error # 5. An attempt to save money, namely, contacting inexperienced workers or a little-known ventilation cleaning company.The incentives to save the family budget are good, but it will be similar to cleaning the ventilation yourself, that is, bad. So, during all the work, he will not clean all the grooves, he may break something, or he will use the cheapest means, he will not disinfect, and so on.

It is much better to pay extra and get a qualified specialist who knows his job and does not save money. If you do not follow the advice, then you still have to call a good master later, but in this case the overpayment will be much higher.

How do I know if cleaning is needed?

In order to determine the quality of the ventilation system, use special devices, for example, anemometers, which will show the speed of air movement. When measuring the cross-sectional area of ​​the channel and taking into account the measured speed, it is possible to calculate what volume of air passes through a unit of time, and then compare the result obtained with the norms specified in SNiP and DBN. But everything is not so simple, since the result must be taken into account with climatic and atmospheric conditions.

It will not be a secret for anyone that, according to the laws of physics, warm air rises upward and tries to mix with cold air. This is the basis of the ventilation principle. Through windows, doors and other leaks of the house, air enters the room, and heated and exhausted it comes out through the exhaust ducts into the systems outside the house. But keep in mind that the draft depends on the air temperature outside, and in the heat, the opposite effect may appear, and the heat from the street will tend to the apartment, which will greatly complicate the air exchange. Natural ventilation works much worse in the summer.

For this reason, it would be silly to talk about the method of diagnosing ventilation by the "attach a piece of paper to the grate" method. Although if the leaf does not fall off the grate and holds, then the traction is considered good, but these are approximate signs, and even during the day they can change.

Another reason for poor-quality ventilation is the measures that are carried out for the insulation of buildings and houses. When installing completely sealed windows and doors, as well as when insulating walls, access to clean air is completely blocked, and the hood will stop working completely. For this reason, you should provide the necessary air supply and exhaust in the office, house or apartment.

It is much more difficult to understand at what time it is required to clean and disinfect air ducts of ventilation systems with mechanical systems. They need to check and compare the calculated real parameters that were provided during the design. Such a system must ensure the design flow rate, frequency rate, speed, temperature and purity throughout the technical documentation. You also need to check the condition of the air duct, the cleanliness of the grilles, valves, filters and fan blades, the condition of the drive, electrical control, heat exchanger and drainage system.

So, it turns out that only professionals should evaluate the quality of ventilation and carry out all the necessary measurements.

Only people with deep knowledge in this matter will be able to correctly assess the condition, find out why the hood is clogged or does not work well, how well the ventilation works and for what reasons it makes noise. This is responsible, and only professionals can be entrusted with such a matter.

How exactly does it clean the ventilation?

The natural ventilation system in an office or home is served with using the simplest devices, such as flexible duct brushes that extract dust from ventilation shafts.

The mechanical ventilation system is cleaned and disinfected by a whole team of specialists. The entire system is inspected, the operating parameters are checked, and then the tightness is checked, and a plan for the cleaning of each section is created.

For this, powerful equipment is used, namely, brushing machines, vacuum installations, video monitoring systems, filtration boxes, etc.

Here you need to highlight the following factors:

  • Brush machines are connected to different parts of the disconnected system in order of priority, which clean out all blockages inside the duct, and on the opposite side a vacuum machine works, which sucks in all the dust into the filter box. Untreated air passes through fine and coarse filters.
  • To remove grease contamination in the ventilation system of restaurants, bars and cafes, use alkaline solutions, steam generators or foam generators.

Air ducts with a large cross-section are cleaned with compressed air.

  • Video cameras are used to control cleanliness.
  • Local washings are carried out from all walls according to the presence of contamination and the degree of contamination is determined. According to this analysis, disinfection is selected and the solution is sprayed onto all the inner walls of the air duct.
  • Cleaning and disinfection of air ducts in ventilation, as well as surfaces of valves and fan blades and silencers is carried out manually.
  • When the work is over, the system is started up and operational, and all results are documented.


Ventilation in an apartment, house or office, as well as at work and in a medical institution is very important. When cleaned regularly, this ensures health and clean air for all people.

Cleaning, disinfection, systematic control - all this is necessary for good performance and long-term operation of equipment inside the system. Only with full compliance with the complex maintenance requirements will you be able to ensure 100% productivity and efficiency.