Frequency rate of air exchange in office premises: norms and rules for the organization of proper air exchange
You must admit that working in a stuffy office with stale air is very unpleasant - you get a feeling of great tiredness, a constant desire to go to sleep, and also unmotivated irritability. The reason for this condition is extremely simple - insufficient oxygen in the inhaled air.
That is why ensuring the correct air exchange in offices is one of the most difficult problems in modern construction. To determine the standards and requirements regarding what should be the rate of air exchange in office premises, numerous experiments and studies have been conducted.
The result of these works is the preparation of regulatory documents containing standards for the frequency of air exchange. It is impossible to provide them without proper arrangement of the ventilation system.
The content of the article:
- Legislation and requirements
- Office ventilation requirements
- Varieties of organization of air exchange
- Designing an office ventilation
- What to consider at the design stage?
- Conclusions and useful video on the topic
Legislation and requirements
Air exchange standards set forth in SP 60.13330.2016, are determined by the purpose of the office and the number of people working in it.
The document contains the following requirements for air exchange rates (per person):
- premises used for operational meetings - 60 m³ / h;
- manager's office - 60 m³ / h;
- reception of the head - 40 m³ / h;
- meeting room - 40 m³ / h;
- open space (open office) - 30 m³ / h;
- corridors and halls - 11 m³ / h;
- latrines - 75 m³ / h;
- smoking rooms - 100 m³ / h.
Ensuring adequate ventilation is important not only from the point of view of industrial safetydreams. It is about people's health and quality of work.
Stale, stuffy air does not contribute to increasing the working capacity of the team, which means that the work efficiency is deteriorating and the company suffers economic losses. Failure to comply with SNiP 41-01-2003 requirements will not only cause penalties, but also entail many functional problems.
Office ventilation requirements
The rules are extremely simple and straightforward.
In order to comply with the multiplicity of air exchange in office rooms, the following things must be provided:
- Systematic inflow of O2-enriched air.
- Discharge of exhaust air with a high concentration of CO2.
- Removal of dust and other contaminants of the supply stream.
Compliant with all the above requirements and considering air exchange rates per person, the ventilation system will ensure proper ventilation in the room, even if natural ventilation of the office is not carried out at all.
For example, in some business centers, office premises are located in the underground floors and generally do not have windows.
There are also requirements relating directly to the ventilation system itself. Only a 100% ventilation system corresponding to them can be used in a modern office.
Here are the most significant of the criteria:
- Profitability of energy consumption.
- The ability to adjust the functional parameters of the system, ease of management.
- Functionality combined with compactness.
- Easy installation, no need for serious repair work.
The competent organization of air exchange allows us to rationalize the use of commercial premises.
Moreover, the conditions in the office located on the 3rd floor and, for example, in the basement, will not differ.
Varieties of organization of air exchange
How will the ventilation issue be resolved is decided by engineers and designers. The main thing is that everything meets the requirements.
Depending on the features of the building and the functional, engineering characteristics of the room in which air exchange is to be provided, one of the following systems is selected:
- supply and exhaust ventilation - the most popular solution when equipping all kinds of offices;
- forced-air and exhaust with recovery heat;
- supply and typesetting supply and exhaust;
- central air conditioning system.
In view of its functional features, the first two systems were most popular.
In Europe, systems with recovery are installed almost everywhere. Although each of these options has its advantages.
In general, the choice is differentvisibility The ventilation system is due to several factors.
The most significant of them are:
- office space;
- layout and number of working people;
- the number of working equipment in the room.
All these criteria should be taken into account when choosing the type and power of the installed system. For a better understanding of the issue, it makes sense to consider in more detail all the features of each of the above types of ventilation systems.
Supply and exhaust system
The principle of operation of this ventilation system can be characterized as follows: through the street openings with grilles, fresh air flows into the supply device, where it is cleaned, heated or cooled.
And only then, through branching, he enters every office building.The system is simple and reliable, suitable for both large and small rooms. With its help, an organized supply and removal of air occurs.
The air inlet function has priority if the office space is located close to the kitchen or smoking room (the air inlet function is intended to prevent smoke from entering other rooms).
It is important to design the supply air supply paths and the location of the supply air inlet openings so that the formation of “stagnation” in the air flow is excluded by definition.
In parallel with this, there should not be a draft feeling. Another important function of ventilation is to ensure the most uniform distribution of incoming fresh air throughout the premises.
The demand for supply and exhaust equipment is due to its many advantages. The vast majority of offices are equipped with it.
First of all, you need to pay attention to the following advantages of this system:
- replacement of air enriched in carbon dioxide in the air with fresh air is ongoing;
- in addition to the fact that the air flowing inside the offices is pre-cleaned, it is also heated;
- humidification of air flow is provided. This feature is not available on all models of ventilation devices;
- energy consumption is saved.
A simple and universal scheme that allows you to create a project for almost any room, regardless of architectural and design features. Even if it is a pre-revolutionary building.
At the same time, one cannot fail to mention the disadvantages of the use of supply and exhaust ventilation:
- Noisiness - due to the rotation of the fan blades.
- The possibility of cooling the incoming air flow in the warm season is not provided.
Accordingly, it becomes necessary to install specialized equipment used to normalize the climate inside the building.
And a high level of comfort with such noise can not be provided.
Features of the supply ventilation system
Forcing a fresh air stream inside is ensured by supply ventilation equipment.
High CO2 content air is vented through the openings of the ventilation shaft.
The use of forced ventilation in the office provides several advantages.
The most important ones are listed below.
- the system provides an intensive air circulation of the spatial environment and a continuous supply of O2-enriched air to all rooms located in the building;
- incoming air masses are cleaned qualitatively;
- heating of the incoming air flow to the desired temperature is ensured. Due to this, it is possible to provide the proper level of comfort;
- energy consumption is saved. This is made possible by equipping the supply and exhaust devices with a heat recuperator. The device makes it possible to heat the incoming air flow with heat that is removed from the offices - it is possible to "put into business" up to 80% of the energy, otherwise it is wasted. The mixing of flows does not occur, the quality of the supply air remains unchanged.
Disadvantage: the installation of forced ventilation is a rather expensive procedure. At the same time, its value cannot be called unjustified.
Central air conditioning system
Using the system is relevant in small offices - ducted air conditioners provide optimal ventilation and purification of air flow in small areas.
Most often, a corridor or a bathroom becomes a place for installing a channel air conditioner.
The indoor unit is not designed by the system. There is no way to set a specific temperature for each cabinet. For offices, the area of which exceeds 200 sq.m. not used.
Also, for the arrangement of ventilation systems, central air conditioners are used. These devices are used to ventilate large areas, and the air conditioners themselves differ in considerable dimensions. Most often, they are installed on the roof of the building or in the basement.
An important advantage of central air conditioners is their multifunctionality. The device includes several sections.
Mandatory elements are elements that provide:
- cooling / heating;
- noise absorption;
- humidification of air.
An expensive but profitable solution. Most often, it is used in buildings divided into production and office parts.
Designing an office ventilation
Given that ventilation is a complex engineering system designed to ensure a constant flow of clean and fresh air, remove harmful compounds and create comfortable conditions, the need to develop a project is beyond doubt.
It should be borne in mind that each ventilation system has its own characteristics. Therefore, a project is developed exclusively for a specific room, adjusted for all its features.
It takes into account:
- The number of personnel simultaneously in the room.
- Requirements for standards of temperature and / or humidity, dust free and other harmful substances.
- Features of architecture - room height, the presence of beams and other utilities.
It is easy to guess that it is almost impossible to take into account all the nuances listed above without drawing up a preliminary draft.
That is why, before starting work, a detailed draft of the ventilation system is compiled.
Attempts to install a ventilation system without first creating a project almost always resulted in adverse consequences.
What to consider at the design stage?
At the stage of development of a draft ventilation system, the following points are subject to coordination:
- Features of the architecture and design of the office building / cabinets.
- The location of the equipment.
- The likely location of the channels through which air will flow.
- Power indicator of electrical installation.
- Availability of water supply, as well as probable condensate drainage paths. Providing free access to the ventilation system.
- The possibility (if necessary) of making changes to the design.
In the design of the ventilation system, make corrections for work air conditioning systems as another source of air exchange is not worth it.
This is explained very simply - only the ventilation system provides adequate air exchange.
Air conditioners are designed to improve the characteristics of the incoming air (temperature correction, moisturizing, purification from harmful components), but not one, even the most modern air conditioner, will provide an influx of fresh, enriched O2, air.
Another issue is central air conditioners with an influx of fresh air, which can provide an air supply that meets all requirements.
The process of designing a ventilation network includes the calculation of:
- Exchange of air flows.
- Communication schemes.
- Heat influx. The calculation is carried out for each room individually, adjusted for technical and design features of the structure.
- Cross-sectional areas of the paths along which air flow is exchanged.
- Pressure loss through the network of ventilation ducts.
- The required power of the heater.
In addition, the equipment necessary for the assembly and assembly of the ventilation network is determined. Project documentation is drawn up and all details are agreed upon.
Conclusions and useful video on the topic
Professional opinion regarding the installation of a ventilation system and ways to ensure adequate air exchange in the office:
Compliance with the requirements of SP 60.13330.2016 and SNiP 2.04.05-91 Change N 2 allows you to provide comfortable working conditions in the office space.
The required air exchange rate can be provided by several types of ventilation systems, with their own advantages and disadvantages. All these nuances must be taken into account when choosing and designing a project.
Have questions about providing air exchange in the office? Ask them to our experts, and we will help solve your problem.