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Natural ventilation systems can be ductless if air passes only through open apertures in external fences, or are ducted when air moves through ducts.

The operation of natural ventilation largely depends on the action of the wind. The wind, running into the building, creates an overpressure zone on the windward side, and a negative pressure zone on the leeward side. Controlled natural air exchange in the workshops of industrial buildings is called aeration. Such buildings are equipped with lanterns with shutters (transoms) that can be opened manually or by special mechanisms. The same opening valves are provided with window openings in the outer walls. By opening them partially or completely, you can create the required air exchange. Aeration is calculated only for the effect of gravitational pressure, since wind pressure is episodic and, as a rule, increases air exchange. Aeration is usually provided in industrial buildings with significant heat emissions.

The advantage of aeration is that air exchange is created without the help of fans, without consuming electricity. However, aeration provides only general exchange ventilation and does not provide cleaning of supply and exhaust air.

Mechanical ventilation systems can provide local ventilation.

The supply systems of mechanical ventilation supply purified air with a set temperature and, in some cases, humidity to the working area of the workshop to ensure the required sanitary and hygienic conditions for people and equipment inside the building. Mechanical ventilation exhaust systems remove dusty and polluted air, purifying it if necessary before being released into the atmosphere.

Supply ventilation systems consist of the following main elements: an air intake device, an intake chamber, which includes an insulated valve, a filter, an air heater (heater) and the fan, the network air ducts and air distributors, as well as regulating devices (diaphragms).

The air intake device is located in the least dusty area of the site, but as close as possible to the supply chamber or on the roof. At the entrance to the air intake shaft or channel, a louvered grille is installed to protect against atmospheric precipitation and from foreign objects. An air intake shaft or channel is made in building structures made of brick or concrete. Sometimes one intake duct feeds several supply systems with external air.

An insulated valve (flap) with manual or electric drive is installed between the air intake device and the filter of the supply chamber. When the fan is not working, the valve must be closed to protect the supply chamber equipment from outside cold air.

The supply chamber consists of a louvered grate, a filter for air purification, heaters for heating it and a fan with an electric motor. Supply chambers can be installed on a foundation or a platform, or suspended from ceiling structures of coatings. No fencing is required for these cameras.

Air ducts of supply systems are usually made of thin – sheet galvanized steel roofing with a thickness of 0.35–1.4 mm. The air ducts can be of round or rectangular cross-section. Metal ducts are quickly mounted, are strong enough and have good tightness. When laying air ducts under the floor, they are made of concrete or brick.

Air distributors (supply nozzles) are designed to distribute supply air. The supply air can be supplied to the working area; for this, the air distributors must have a short torch and a slight velocity of the outgoing air to eliminate the feeling of a draft. When air is supplied to the upper area of the room, on the contrary, the air outlet speed should be higher so that the fresh air stream reaches the working area.

Air distributors are installed in suspended ceilings, some are mounted at a low height above the working area.

A type of supply ventilation systems is air shower, which provides a concentrated flow of air to the workplace. A workplace is a platform with a diameter of 1 m, on which the worker is at least 4 hours per shift or 2 hours continuously. Such an air supply is necessary for intensive thermal (from 300 to 3000 W/m2 or more) irradiation of workers, or for open production processes with the release of harmful gases and vapors, when it is impossible to arrange local shelters. Actually, the scheme of air douching does not differ from the supply ventilation system, but instead of air distributors, showering rotary nozzles are installed.

Air and thermal-air curtains are designed to protect the gates and open entrances of industrial buildings from the intake of cold air in winter. There are two types of curtains: sliding, in which a flat jet of air is supplied either from below or from the sides of entrances and gates at some angle towards cold air, and mixing, when air from the building is supplied to the vestibule between the double entrance doors. Mixing curtains are used in administrative and public buildings, in passageways, etc. Curtains in which the air is preheated in an air heater are called thermal-air, and curtains that supply air without heating are simply air type.

Air-heating units with full or partial air recirculation are often used in air heating systems.

General exchange exhaust ventilation systems usually remove air from the upper, less often from the middle zone of buildings. Before removal, the air in general exchange exhaust systems usually does not undergo cleaning. General exchange exhaust systems can be channelless if the air is removed by roof fans that are installed on the floors, and ducted. In ducted exhaust ventilation systems, air is sucked into air intake apertures or grilles, it is fed through the ducts to the fan and, after passing the exhaust shaft, enters the atmosphere. To protect the exhaust shaft from atmospheric precipitation, an umbrella is installed above it, and the air ducts are blocked with a flap when the fan is not working.

Local exhaust ventilation systems are designed to take harmful emissions from the places of their formation with the help of shelters or local suction, transport polluted air, clean it in filters or dust collectors and release it into the atmosphere. Local suction and shelters have the most diverse design and shape: these are umbrellas, fume hoods, full shelters, side and ring suction at baths and shaft furnaces, suction panels, casings, etc.

Many harmful substances released during technological processes actively affect local suction pipes, air ducts, fans, filters, causing their severe corrosion, in addition, they can be explosive and fire-hazardous. In these cases, air ducts and other devices in contact with an aggressive environment are made of materials that are not subject to intense corrosion by the moving medium (corrosion-resistant alloy steels, aluminum, titanium. metal, vinyl, polyethylene, etc.), or apply special coatings of steel ducts with acid- and alkali-resistant dyes, enamels and varnishes. In such systems, fans and other equipment are installed in an intrinsically safe protected design.