Artificial (mechanical) ventilation is the movement of air due to mechanical motivation using special devices – fans. Compared to the natural one, it is more effective due to significant pressure, and the inflow and exhaust are not dependent on air temperature and wind speed. Its main disadvantages are the need for sound insulation and high construction and operational costs. Depending on the purpose of the room, it can be separate (supply or exhaust) or combined (supply and exhaust), as well as local – for one room or workplace, or general – for the entire building. With the help of special devices, the supplied air can be filtered, cooled or heated, dried or humidified, that is, an air conditioning system is organized, of which special devices are local air conditioners. The efficiency of ventilation is determined by the proper organization of air exchange (supply and removal of air) taking into account the particular purpose of the room.
At the same time, there is a basic rule: removal of air by exhaust installations should be carried out directly from the places of hazardous emissions or from areas where the air has the greatest pollution. The amount of air supplied to the room or removed from it is calculated according to the formula given in the practical part.
Hygiene requirements for ventilation
1. Ensure the necessary purity of air.
2. Do not create high and unpleasant air speeds.
3. Maintain, together with heating systems, the physical parameters of the air environment — the necessary temperature and humidity.
4. Be trouble free and easy to operate. 5. Be silent and safe.
Organization of ventilation in hospitals
Ventilation in hospital buildings should exclude the flow of air masses from the “dirty” (“G”) areas of the premises to the “clean” (“H”) rooms. The category of departments (rooms) for the respective zones is shown in Table 6, according to SanPiN 22.214.171.1245-03 “Hygienic requirements for the placement, construction, equipment and operation of hospitals, maternity hospitals and other medical hospitals”.
The buildings of medical hospitals and maternity hospitals should be equipped with systems of supply and exhaust ventilation with mechanical stimulation, with the exception of infectious wards. In addition to the supply and exhaust artificial ventilation, in all rooms of medical and obstetric hospitals, except for rooms requiring a high-purity regime (“OCH”, “Ch”), natural ventilation should be arranged by means of window leaves, folding transoms and other devices in window covers max. and external walls, as well as ventilation ducts without mechanical induction of air.
Outside air for ventilation and air conditioning systems should be taken from a clean area at least 2 meters above the ground. Outside air supplied by the supply units must be cleaned of dust by filters of coarse and fine structure, which are placed in the ventilation chamber. When air is supplied to the operating rooms, anesthesia, obstetric, intensive care, intensive care rooms and for patients with skin burns, the air is additionally cleaned with bacterial filters that are installed closer to the places where the air is released into the room. Filters should be cleaned at least once a month, and if bacterial performance worsens, they are replaced. Bacterial contamination of the air environment of the above premises requiring high purity should not exceed acceptable levels in accordance with SanPiN-03 g.
Ventilation units (supply and exhaust) must be turned on 5 minutes before the start of work and turned off 5 minutes after its completion. In addition, rooms where the medical and technological process is accompanied by the release of harmful substances into the air must be equipped with local suction or fume hoods. In either x and Regla menting the chemical composition of the air (the content of harmful, including medicinal vesch EU ETS) in accordance with vysheuka -bound SanPin.