Microscopic harmful microorganisms are often the main cause of the spread of infections and the appearance of quite serious diseases. In order to reduce the risk of their transmission from a sick person to a healthy person, a wide variety of disinfectants are used, mostly used in hospital conditions. In this article, we will consider the possible types and methods of prevention, as well as describe the methods of preparation of chemical compounds and the safety of their use.
Functional purpose
To understand the functions of disinfecting solutions, first you need to determine what it is. In most cases, this term means various chemical compounds that are designed to destroy infectious agents on the surface they treat. 
For the same purpose, large concentrations of antimicrobial drugs for external use can be used, but, anyway, the goal is the same for everyone - to quench the source of infection and disinfect the room to safely find people in it.
For the most part, disinfectants are used in medical institutions, although they are often used in schools and kindergartens, with a slight adjustment of the composition.
Did you know? The favorite places of the human body for germs are the head (its hairy areas) and hands. Usually, microorganisms hide under the nails, on the side parts and in the folds of the palms.
Types of disinfection
Depending on the specific location and level of infection, prophylactic and focal disinfection are distinguished, and the latter is further subdivided into current and final. Consider each species more closely. 
Prophylactic
This option is relevant only as a preventive measure that does not allow the appearance or spread of the disease. Preventive disinfection should be performed on a regular basis, especially in places where the risk of infectious outbreaks is greatly increased.
First of all, we are talking about hospitals, clinics, medical consultation centers, places for mass gathering of people (for example, railway stations, public restrooms, transportation), food industry enterprises, schools and preschool institutions.
To maintain hygienic conditions, Brovadez-plus, Farmiod and Virotz are used in animal husbandry, and potassium permanganate and iodine are used in plant growing.
In addition, based on the nature of the activity of a specific facility, preventive treatments should be carried out by business organizations and other enterprises where there is an increased risk of the emergence and spread of pathogens.
The main methods of this type of disinfection can be considered cleaning of work surfaces and bathroom premises, washing clothes, removing various biological and chemical wastes, washing hands and dishes, and the latter should be regularly carried out at home. 
Best of all, if all these treatments will take place with the use of bactericidal cleaners or specially prepared disinfectants (if we are talking about an increased risk of infection).
Focal
This type of disinfection involves the use of more serious means, as sometimes you have to face a confirmed focus of infection or suspicion of its spread. Often this variety is divided into current and final.
The first is performed indoors with a sick person, and the second provides for decontamination after it has been transferred or discharged.
Current
Current disinfection - an obligatory condition in hospitals or at home, where there is a direct source of infection (for example, a sick person). Frequent processing is characteristic of infectious departments of hospitals, operating rooms, manipulation and laboratories, whose employees deal with potentially dangerous biological specimens daily. 
The main task of such disinfection is to prevent the spread of pathogenic microorganisms and their contact with healthy people outside the already existing focus.
The most common reasons for this type of disinfection include:
- long stay of the patient in the concrete room before his hospitalization;
- treatment of the patient at home until the recovery;
- finding the carrier of infection in a hospital before being removed from the dispensary.
The organization of disinfecting activities in apartments is usually performed by the medical officer who identified the patient, and is carried out by the household itself.
Sometimes all organizational measures are taken by employees of the sanitary-epidemiological service, but this is more likely for medical institutions and individual enterprises.
Important! Disinfection conducted by workers of the sanitary-epidemiological service is considered an ineffective way to solve the problem, since the implementation of many measures is delayed and practically not controlled in any way.
Final
This option of disinfection works is performed to clean the room after finding the patient or other infected objects in it. 
As before, the main purpose of such treatment is to prevent re-infection by eliminating all pathogenic factors.
Mandatory final antiseptic treatment should be carried out after discharge, isolation or death of the patient, especially when it comes to the possibility of the spread of such terrible infections as plague, cholera, typhoid fever, leprosy, ornithosis, diphtheria, fungal diseases of hair, skin and nails.
Also, this type of disinfection will be no less demanding in the foci of infectious diseases or in case of suspected viral hepatitis, poliomyelitis, dysentery, acute intestinal infections, etc. In the case of low-risk infectious diseases, final disinfection is performed taking into account the overall epidemiological situation.
Disinfection methods
In each of the cases described, one can use one's own methods for eliminating bacteria, which are divided into biological, chemical (the largest group) and physical.
Biological
In this case, the issue of harmful microorganisms is solved by using other microbes - thermophilic or antagonists. 
This option is appropriate for the disinfection of wastewater in irrigation fields, in places of collection of garbage, waste, biological residues and compost.
It is mainly used in the veterinary field and at the enterprises, and in urban conditions it practically does not occur.
Chemical
This group includes the most popular methods of decontamination of the territory - using a variety of chemical compounds. Disinfectants based on them destroy the walls of bacteria and viruses and neutralize biologically toxic substances.
The high frequency of use of this particular method is due to the possibility of using chemicals on a wide variety of surfaces, without causing them any harm. 
The main requirements for decontamination solutions of this kind are relatively high safety for the human body, good solubility in water and the ability to maintain their disinfecting properties when in contact with organic derivatives.
The choice of a disinfector is made on the basis of the nature of the pathogen, the surrounding conditions and the type of surface, but vircon and chlorhexidine are considered the classic variants.
Physical
Among the physical methods of dealing with harmful microorganisms, boiling, calcining, exposure to sunlight, water vapor, or processing rooms with UV lamps are most often used. In extreme cases, infected items can simply be burned.
The causative agents of infectious diseases are unable to cope with high temperatures, therefore heat treatment is considered one of the most effective methods to eliminate them. 
The appropriateness of each of these methods is determined based on the type of surface being treated, the characteristics of the room and other external factors.
Important! To achieve the most effective result of the disinfection process, it is important to use several proven methods at once. For example, UV irradiation is well combined with wet cleaning, and for water purification you can first pass it through the filter and then boil it further.
Separately it is necessary to allocate and mechanical disinfection methods, based on the disposal of an infected object. In most cases, this option is used when disinfecting the soil by removing its top layer.
Find out why and how to disinfect the ground before planting seedlings.
Classification
For the disinfection of any surface or the whole room can be used almost any form of chemical agents, ranging from aerosols, pastes, liquid solutions and emulsions to powders, tablets and water-soluble granules. 
In general, the following classification of disinfectors is considered to be the most common:
- Substances containing chlorine. Presented mainly chloramine, bleach, calcium hypochlorite. This is not only the oldest method of dealing with germs, but also one of the most convenient and large-scale, because it allows you to remove different groups of infectious agents at a time. The main drawbacks of using such agents are the damaging effects on many surfaces, the toxicity to humans and the environment.
- Substances based on active oxygen (usually hydrogen peroxide, potassium permanganate, Permur). All preparations from this group are distinguished by low toxicity and a high level of environmental friendliness, at the same time representing a serious threat to the majority of microbes known today.
- Surfactant Based Compounds (for example, Veltolen, Vapusan or Biodez-Extra). They are great for cleaning surfaces and at the same time relieve them of harmful microorganisms, are easy to use and do not harm the coating. The main drawback is the ability to combat a limited number of pathogenic microbes.
- Preparations incorporating tertiary amines (for example, "Amiflayn"). This is a relatively new and low-toxic protection against infection. All compositions are characterized by a wide spectrum of action and excellent detergency.
- Alcohol disinfectors (represented by ethanol, isopropanol, propanol). They do an excellent job of neutralizing a large part of the microbes, they are easy to use and can be used for almost any type of surface, leaving no trace on them. However, the shortcomings of alcohol disinfectors often do not allow their use in the conditions of enterprises or some industrial facilities. The fact is that these are explosive and flammable substances, which, moreover, require preliminary cleaning of the treated surface.
- Aldehyde formulations (usually found "Glutaral", "Bianol", "Lizoformin"). Most of them are characterized by high efficiency and a wide spectrum of action, while maintaining the integrity of the treated surface. The main disadvantages are a high level of toxicity, the need for pre-treatment of other contaminants.
- Guanidine formulations (among the most popular "Bior", "Polisept", "Demos"). These are low-toxic substances that can form a bactericidal film (prolongs the protective effect) and are carefully applied to many surfaces to be treated. As in the previous cases, before using the tools, you will have to clean the surface.
- Phenol Based Compounds ("Amotsid"). The main advantage is the duration of the harmful effects on microbes, and the disadvantages include high toxicity, which is why such compositions are rarely used in urban environments.
Did you know? The alkaline composition of ash and sand allows them to destroy many bacteria, so that they are considered the best substitutes for soap - this is recognized even by doctors.
Precautionary measures
When working with chemicals, you should always be extremely careful, as there is a risk of their detrimental effect on human health.
In the conditions of hospitals or other specialized institutions, a specially trained person is engaged in the preparation of all disinfecting compounds, and all work on the connection and mixing of certain substances is carried out in a well-ventilated area with the obligatory use of rubber gloves, protective suits and gauze bandages (possibly special respirators). 
Given the fact that all means used for disinfection are distinguished by a high level of toxicity, it is not surprising that there are a number of rules governing the possibility of working with them.
These requirements include:
- Admission to work with disinfecting solutions only of citizens who have reached the age of 18 and who have been instructed (the employee is provided with information regarding safety, prevention and first aid in case of poisoning, etc.);
- removal from work with chemicals of persons suffering from allergic reactions;
- All work on the disinfection of linen, dishes or other things that were in the focus of infection, are carried out only in specially designated areas with a good ventilation system;
- In the same well-ventilated premises, the creation of disinfectants should be carried out, and all containers with solutions and tools placed in them should be tightly closed with a lid;
- stocks of disinfecting solutions must be placed in closed spaces with limited access by people;
- all stages of washing and disinfection must be performed in a precise sequence that will ensure complete removal of chemical particles and detergents from surfaces;
- after contact with chemical substances, all workers must wash their hands and soften them with cream.
These general safety rules are relevant in all cases of contact with disinfecting solution and must be fully observed. In case of contact with the eyes, they are washed with plenty of water.
Important! More specific safety requirements are usually set out in the "Guidelines" for the use of a drug.
Cooking rules
To prepare any disinfecting solution, you will need enamelled or glass containers with hermetically attached lids, measuring spoons and mugs, wooden chopsticks for stirring, water and disinfectants.
The sequence of all actions is as follows:
- Pour into the measuring cup the right amount of water.
- Cast in a separate container 1/3 of the liquid.
- Pour or pour the required amount of disinfectant.
- Mix all wooden stick.
- Add the remaining water and mix everything well again.
- Tightly close the solution with a lid.
- On the label we indicate the date of preparation, the name of the chemical used, its% and the boundary date of use (medical workers additionally put their name and signature).
To prepare a bleach solution, 1 kg of dry matter must be diluted in 9 liters of cold water, having previously ground it with a spatula.
Chloric lime is also used in the processing of greenhouses in the spring, in the fight against diseases and pests of currants, asters, lilacs, phloxes, as well as melons, potatoes, eggplants, zucchini, tomatoes.
Such a mixture before use should settle for a day, with two to three-fold stirring. The finished solution is poured into a dark bottle, hermetically sealed with a cork. If you need to prepare a solution of different concentrations, you can follow the following recommendations:
- 0.1% - to 9.9 liters of water accounts for 100 ml of a 10% bleach solution;
- 0.2% - for 9.8 l of water you need to take 200 ml of the same solution;
- 0.5% - per 9.5 l of water 0.5 l of 10% bleach solution;
- 1% - for 9.0 l of water take 1 l of 10% solution.
Chloramine blend is prepared immediately before use, using the following proportions:
- 1% - 10 g of substance is mixed with 990 ml of water;
- 3% - 30 g of chloramine is combined with 970 ml of water;
- 5% - 50 g of substance dissolved in 950 ml of liquid.
Of course, after mixing in the tank with the composition, it is necessary to write what and in what quantity was used.
Storage
Proper storage of all prepared disinfecting solutions is one of the first safety requirements. First of all, you need to take care of a separate room for the organization of such a mini-warehouse (it is equipped with all the necessary racks and shelves for the separate storage of disinfectants and conventional detergents).
Important! Мелкотарные дезрастворы следует размещать на металлических стеллажах, а стеклянные бутыли лучше поставить на поддоны.
Во-вторых, the interior of the room should be made of materials that easily tolerate exposure to chemicals (it can be tiles, tiles or oil paint). 
Thirdly, it is important to provide a complete hood that will constantly remove harmful fumes from the room. The temperature in the storage of decontamination solutions should always be within 0 ... +18 ° С.
As for the storage process itself, all solutions must be placed in separate containers with clearly marked data on the labels (name, value, concentration of the active substance, date of manufacture, shelf life, etc.).
The stock of disinfectants for the whole month should be stored centrally in the warehouse, away from personal belongings and foodstuffs. Also it is necessary to exclude possible contact with solutions of unauthorized persons.
