Air quality is one of the most important indicators of the human environment. Any public place should be equipped with a ventilation system that will remove polluted air from the room and replace it with clean outdoor air.
High requirements for ventilation of public buildings are dictated not only by sanitary and hygienic standards, but also by concern for the comfort of visitors. After all, you must admit, it is not very pleasant to be in a room where there are many smells in the air, and not always pleasant ones.
Next, we will tell you what regulatory acts regulate the climatic regime in the premises and how ventilation can be arranged in rooms for various purposes.
The content of the article:
- Microclimate in various types of premises
-
Ventilation system implementation options
- General exchange type ventilation
- Supply and exhaust ventilation with recuperation
- Air handling units
- Smoke and fire prevention ventilation
- Conclusions and useful video on the topic
Microclimate in various types of premises
The ventilation system diagram is developed during the design of the building. Engineers and designers take into account the specifics of the structure, architectural features, the difference in climatic conditions in the premises.
Before supplying it to the room, the air must be heated in the cold season. For this, duct heaters are used in supply ventilation systems.
To help specialists come normative documents that establish the boundaries of the limit values of the microclimate:
- SP 7.13130.2013;
- SP 60.13330.2016;
- SP 252.1325800.2016.
Before starting work on air conditioning system design and ventilation of public buildings, it is necessary to determine which category the building belongs to.
By GOST 30494-2011 highlighted categories:
- Category 1. It includes all rooms in which people are in a state of rest and rest, lying or sitting.
- Category 2. The building is intended for mental work or study.
- 3a. The premises are characterized by a mass stay of people without warm outerwear, mainly sitting.
- 3b. The premises are occupied by people in street clothes, as a rule, sitting.
- 3c. In the premises there are people in street clothes, standing.
- 4 category. Places for outdoor sports.
- Category 5. Premises of this type assume the presence of people in a half-naked form (swimming pools, gyms).
- 6 categories. This category includes premises where people stay for a short time (storage rooms, bathrooms, lobbies, corridors).
Engineers are faced with a rather difficult task to ensure optimal parameters in each room.
Installing a supply fan on the roof is an example of rational use of the area of a public building, which saves space in the room
According to the norms, the room should constantly receive 20-30 m3 fresh air for one person. Now there are controversies around this meaning. With such an inflow, a draft can occur, which is very unpleasant in the cold season, when the heating elements of the ventilation simply do not have time to warm the air flow to a comfortable temperature.
Another method for calculating the required air exchange is based on the formula:
V = 3 m3 * S,
where S - area of the room.
Accordingly, there are 3 cubic meters of air per square meter. This method is used, as a rule, to calculate the required inflow in the dwelling, but SNiP 31-05-2003 allow such a calculation for offices in an administrative public building.
In calculations for some premises, such as a toilet, a smoking room, a kitchen, the air exchange rate is used as a value that determines the parameters of the ventilation system.
This is a value that characterizes how many times the entire volume of air in the room will be replaced within one hour. For a kitchen, the minimum permissible value is 3 rpm, for a toilet - 5 rpm, for a smoking room - 7 rpm. Such a calculation is only suitable for small rooms in which people are for a short time.
For small branches general exchange ventilation is more rational to use round duct fans, they can be installed in any position
Ventilation system implementation options
The implementation of high-quality ventilation and air conditioning systems in public spaces is a guarantee of comfort and well-being of people. There are several basic technical solutions for these engineering systems.
General exchange type ventilation
The exhaust part of the ventilation system is needed to remove polluted air, excess moisture and heat from the room.
Its correct operation depends on a constant supply of air. To do this, supply ventilation is needed, supplying fresh air from outside the room.
Within one floor, air ducts are routed along the ceiling, later, when the system is fully assembled, they can be hidden behind a suspended ceiling
Type-setting exhaust ventilation consists of: external grille, fan, automation unit, air ductshoods (kitchens, laboratories), inner grilles or extractor diffusers.
For supply ventilation, the following components are needed: an external grille, filter, air heater, muffler, humidity, temperature, frost sensors, fan, air ducts, internal wall or ceiling grilles, supply diffusers.
This type of ventilation is most commonly used in public buildings. Several branches are mounted in the building general exchange ventilation, not communicating with each other.
Plus of type-setting ventilation - separate air purification in different rooms, the ability to adjust the power of the air flow in each office. But this engineering solution also has a number of disadvantages. The main one is bulkiness. In buildings where it is not possible to hide the air ducts behind a suspended ceiling, problems arise with the aesthetics of this design.
When ventilation is interfloor, vertical air ducts are mounted by extension from above or from below.
In cases where the installation of a suspended ceiling is not possible, the air ducts cannot be hidden behind it. The ventilation system is laid in an open way, the air ducts are decorated in accordance with the interior of the establishment
Some bars and restaurants use air ducts as part of their decor. In this case, stainless steel air ducts are usually used. In general, the neatly mounted ventilation fits into the interior of the establishment.
To suppress noise, the ducts are covered with an insulating material that effectively prevents propagation of sounds between separate rooms and practically reduces the noise of the air in themselves air ducts.
This ventilation system is suitable for buildings with a large number of separate offices.
Supply and exhaust ventilation with recuperation
This ventilation system differs from the previous version by the presence recuperator - surface type heat exchanger. Installed at the intersection of the supply and exhaust ventilation branches.
The air removed from the room leaves heat on the plates of the recuperator. The air that enters the supply system is heated by its ceramic plates.
A recuperator in the ventilation system heats fresh air to a comfortable temperature. This energy efficient device allows you to save about 20-30% of heat
Non-return valves in the recuperator housing prevent air from escaping between the ventilation branches.
Recuperation allows significant savings in heating costs. This advantage of the recuperator is especially noticeable in a large room: a conference hall, a cinema, an assembly hall.
Air handling units
The use of a ventilation unit scares off many building owners due to the high price of the unit itself. It is an all-in-one device - the main elements are located in the case.
Some models are equipped with an air cooler. Unfortunately, it is difficult to use it for air conditioning a large number of rooms for different purposes. This is due to the impossibility of setting an individual temperature regime for each separate room.
The use of ventilation units will save you from noise and unnecessary hassle with the arrangement of ventilation and guarantee a minimum of hassle with the maintenance of the ventilation system
Air handling units are the simplest option for organizing a ventilation system. Quite compact device does not take up much space in the ventilation chamber.
Due to the fact that the fans are located inside a well-insulated case, the noise level from air handling unit below. Maintenance of installations is much cheaper than typesetting systems. Their disadvantage is the need to install additional ventilation equipment in bathrooms, smoking rooms, server.
Smoke and fire prevention ventilation
All ventilation equipment must be installed in accordance with the fire regulations of SP 7.13130.2013. It is impossible to neglect these simple rules when developing a circuit and installing. Any building, and even more so a public one, must be equipped with a fire and smoke ventilation of proper quality.
The spread of fire and smoke through the duct system is a significant problem in a fire. To combat it, fire dampers with a temperature sensor are mounted in the air ducts.
Under normal conditions, it is constantly open. When the temperature rises to an extreme, a sensor is triggered, which activates the valve drive. After closing, the seal applied to the edge of the valve expands to fit as tightly as possible to the duct.
Smoke in the premises impedes evacuation and complicates the work of firefighters. It is impossible to completely get rid of the smoke, but you can minimize its harm by installing back-pressure fans and smoke exhaust.
Smoke exhaust fans are needed to remove the smoke-air mixture from the room. Modern models are capable of operating at temperatures of 400-600 ° C for about 2 hours
Smoke ventilation back-up fans are necessary to provide people on the escape route with clean air. By forcing air in crowded places (evacuation corridors, stairwells), it increases the pressure, preventing smoke from entering there.
Conclusions and useful video on the topic
How the ventilation systems are installed can be found in the following video:
Ignore fire safety regulations or SanPiN it is impossible, despite the high cost or inconvenience of their implementation. The number of technical solutions for ventilation of public buildings is quite considerable.
For each project, you need to select and look for the way to implement the ventilation system, which will be suitable for the stated requirements. But, if there is not enough experience in this area, it is better to turn to specialists who will help you correctly design and equip the ventilation system.
Please ask your questions on the topic of the article, share your experience and valuable advice on arranging ventilation. The communication block is located below.
