Air exchange rate for industrial premises: tables, SNiPs

Proper heating and insulation play crucial roles in maintaining the ideal temperature and comfort level in any type of building, be it residential or commercial. But attaining ideal conditions also necessitates making sure air exchange rates are sufficient. In industrial settings, where multiple processes produce heat, dust, and fumes, careful air exchange management is necessary to maintain a healthy indoor environment. This article examines the importance of air exchange rates in industrial environments, offering useful insights and citing pertinent standards like SNiPs (Construction Norms and Regulations).

Gaining an understanding of the air exchange rate concept is essential to appreciating its significance in industrial settings. In a nutshell, it’s the quantity of times during a given period of time that the air inside a space is replaced with new air. A higher air exchange rate is necessary in environments with pollutants or contaminants to guarantee their removal, preserve air quality, and protect workers’ and residents’ health.

The Russian term for construction norms and regulations is SNiPs, and it refers to standards and guidelines for a number of building-related topics, such as ventilation and air exchange rates. These regulations provide important information about the appropriate air exchange rates for various industrial facilities based on the kinds of activities that are conducted there, how big the space is, and how many people work there. Managers of industrial facilities can maximize energy efficiency and guarantee adherence to safety and health regulations by following these standards.

Engineers and facility managers find tables with suggested air exchange rates for various industrial settings to be invaluable resources. These tables classify industrial spaces according to their intended use and offer recommendations for the appropriate air exchange rate while accounting for various elements like the kind of pollutants produced, occupancy levels, and ventilation system effectiveness. Stakeholders can achieve optimal indoor air quality and comfort by using these tables to guide their informed decisions regarding ventilation system design, operation, and maintenance.

Moreover, for industrial facilities to operate sustainably and economically, it is imperative to comprehend the connection between air exchange rates and energy consumption. Higher air exchange rates can result in higher energy consumption even though they are required to maintain air quality, particularly if they are not properly managed. Thus, employing techniques like heat recovery systems, energy-efficient ventilation systems, and airflow pattern optimization can help reduce energy expenses while still fulfilling air quality regulations.

SNiP	Recommended Air Exchange Rate
SNiP 41-01-2003	1-2 air changes per hour for industrial premises with low pollution levels.
SNiP 23-01-99	2-3 air changes per hour for industrial premises with moderate pollution levels.

What is natural ventilation: the principle of operation in general terms

The principles of physics underpin the functioning of such a system:

• warm air always tends to flow upwards;
• The air will always "go" where the pressure is lower;
• closer to the surface – the pressure is higher, further from the surface – the pressure is lower.

A pressure differential must be created in the space in order to facilitate this kind of air exchange. The following is how it is carried out:

1. Between the street and the room are created "openings": it can be windows or supply dampers, in non-residential premises – just openings. These are the air inlet points.
2. The exhaust pipe is led from the room upstairs. Its opening will be higher than the inflow point. This means that the pressure at the opening in the pipe will be lower than at the inlet point. As a result – air will tend to travel from the point of inflow (i.e. from the street) to the opening of the exhaust pipe.
3. Supply points are located at the maximum distance from the exhaust pipe – so that the air passes through the entire room. Between them there should be no obstacles (closed doors).

In other words, air circulation is created without the need for fans—supply or exhaust fans work equally well in this situation.

Clearly on the principle of operation (video)

Norms of air exchange of different types of premises

Air exchange rates calculated at home

In the course of our work, the issue of adequate air exchange in residential buildings comes up frequently. We are happy to give you the details you need to determine the air exchange adequacy on your own.

The formula m3/h is used to calculate the actual air exchange:

Where Vc is the average air flow velocity, expressed in meters per second (as measured by anemometers, thermometers, microanemometers, etc.);

F is the ventilation duct system’s cross-section, measured in millimeters.

The number that indicates how many times the air in a room is exchanged in an hour is called the air exchange rate.

The following formula determines the air exchange rate:

Where: m3, the room’s internal volume (Vp).

The design standards of the pertinent buildings and structures (SNiP 2.08.01-89, SNiP 31-01-2003, SNiP 2.09.04-87), as well as a number of other normative documents (SNiP 2.04.05-91, etc.), are used to determine the norms of air exchange of various types of rooms.

As an illustration, the following passage from SNiP 31-01-2003, paragraph 9.2, says:

The best standards of GOST 30494-96 should be used when calculating the air quality inside residential buildings. The following table should be used to determine the air exchange rate on the property.

Room	Air exchange rate or value of air exchange, m3 per hour, at least
out of order	in service mode
Bedroom, common room, children"s room	0,2	1,0
Library, study	0,2	0,5
Pantry, linen room, dressing room	0,2	0,2
Gym, billiard room	0,2	80 м3
Laundry, ironing room, drying room	0,5	90 м3
Kitchen with electric stove	0,5	60 м3
Room with gas-using equipment	1,0	1,0 + 100 m3 per plate
Room with heat generators and solid fuel stoves	0,5	1.0 + 100 m3 per stove
Bathroom, shower room, lavatory, combined WC	0,5	25 м3
Sauna	0,5	10 m3 per 1 person
Elevator machine room	–	According to calculation
Parking lot	1,0	By calculation
Garbage chamber	1,0	1,0

In non-working mode, all ventilated rooms (not specified in the table) should have an air exchange rate of at least 0.2 room volume per hour.

The second illustration comes from SNiP 2.08.01-89*. Natural ventilation should be provided for "Residential Buildings" in residential buildings.

The table should be followed when estimating the air parameters and air exchange rate within the building.

Table 1. Air exchange rate and estimated air parameters in residential building premises (SNiP 2.08.01-89*)

Room	Estimated air temperature in the cold season, °С	Air exchange rate or the amount of air removed from the room
Inflow	Exhaust
Living room of apartments or dormitories	18 (20)	–	3 m3/h per 1m2; living rooms
The same, in areas with the temperature of the coldest five-day period (0.92 security) of minus 31°С and below	20 (22)	–	The same
Kitchen of apartments and dormitories, cube: with electric stoves

Utilizing gas stoves

18 – 60 m3/h or above

Not less than 75 m3/h for stoves with three burners,not less than 60 m3/h for stoves with two burners,

90 m3/h minimum when using 4-burner stoves

We understand that it’s easy to become perplexed by all of this, which is why our experts are always available to assist you and restore the standard air exchange rate to any location.

Calculation of air exchange rates

Designers consider normative indicators, such as those found in sanitary and hygienic standards, GOSTs, and building regulations snippets, such as SNiP 2.08.01-89, when calculating the air exchange rate for each individual room. The number of replacements for rooms of a given volume and purpose will be determined using the normative values of multiplicity rates, without consideration for the presence of harmful impurities in the air. The following formula (1) determines the building’s volume:

Where a denotes the room’s length, b its width, and h its height.

Formula (2) can be used to determine the multiplicity Kv given the room’s volume and the amount of oxygen that enters during a one-hour period.

Air exchange rate computation

Where Qvozd is the supply of clean air entering the room for one hour, and Kv is the air exchange rate.

In most cases, the number of cycles of total air mass replacement is not determined using formula (2). This is because the air exchange rate tables are available for all common buildings serving different purposes. Using this formulation of the problem, equipment or technology that provides the required amount of oxygen per unit of time should be chosen for a room of a given volume and air exchange coefficient that is known. In this instance, formula (3) can be used to calculate the amount of clean air that must be supplied in order to guarantee that the room’s oxygen supply is fully replaced in accordance with SNiP requirements:

The number of full cycles of oxygen exchange in the room per hour, or 1/hour, is the unit of measurement for the air exchange rate, according to the formulas above.

Three to four times as much air can be exchanged in a room in an hour when using the natural method. It is advised to use mechanical systems that force the supply of fresh oxygen or remove contaminated oxygen if increasing the intensity of air exchange becomes necessary.

How to calculate supply and exhaust ventilation: the device and design of the system

The supply and exhaust ventilation system is made up of two components: the exhaust system, also known as the "exhaust" system because it is a device that allows air to exit the room, and the supply ventilation system, which delivers fresh air from the street and handles its heating, cleaning, and cooling when needed. The only equipment needed for exhaust ventilation is a noise absorber because, if the hood is very powerful, it will make noise while operating. The exhaust ventilation system is a fairly simple device, consisting of ducting and a mechanism that allows the air to exit. No filters, coolers, or heaters need to be installed.

A crucial query that piques the curiosity of a lot of customers is: how do you compute exhaust ventilation? Calculating the room’s volume in cubic meters is necessary to determine the air removal unit’s capacity. м. and multiply the result by 12. Example of exhaust ventilation calculation:

• kitchen area of 2 X 3 m with a ceiling height of 2, 5 m, the volume of the room is 15 cubic meters. м.
• exhaust capacity 15 X 12 = 180 cu. m. м./ч

Opening a window or shutter will help exhaust ventilation function better. The ventilation system is economical because complex solutions are employed. During the winter months, the outside air warms the air entering the room. To achieve this, a recuperator is utilized, which is a type of heat exchanger that warms the air entering from the street. The recuperator’s mechanism heats the street air without contaminating it with the air that is released into the street.

Design of supply and exhaust ventilation – the stage from which the installation of the ventilation system begins. Before the actual installation, it is necessary to calculate on paper how many meters of pipe are required for the outflow of air, how many ducts are required for the air supply, where all the components and parts of the system will stand, where the grilles and air intakes will be installed. At the stage of design should be considered not only the location, but also the size of the ducts (pipe diameter), the larger the diameter – the greater the air flow can be provided, but modern housing is rarely characterized by high ceilings, so install a fairly wide pipes will not work. The disadvantage of narrow ducts is high noise, so when calculating the supply ventilation, a compromise between noise and pipe size is usually found.

Regarding the air supply capacity, the following computations are typically performed:

• Up to 3 cu. m. should be supplied to living spaces. м. per hour per 1 sq. m. m of dwelling,
• In public areas it is necessary to supply 60 cu. м. /hour per person permanently staying in the building and up to 20 cu. m of dwelling. м. per hour per temporary visitor.

11.3 Notes on the calculation example

11.3.1 When a common umbrella is placed over the kitchen equipment, each unit’s airflow through the umbrella and kitchen emissions should be calculated independently using formula (4) before being summarized.

11.3.2 Verifying the velocity in the dispenser aperture—which should be between 0.2 and 0.3 m/sec—will allow one to determine the air flow from the hall to the hot shop for a given volume.

11.3.3 The air temperature at the air intake of the supply ventilation system unit may be 5 °Ρ–10 °Ρ higher than tn when choosing the design summer air temperature. This is because in densely populated areas, it is necessary to supply 60 cubic meters per hour per person permanently residing in the building and up to 20 cubic meters per hour per temporary visitor.

The role of multiplicity in industrial buildings

A precise multiplicity factor selection enables an accurate air exchange calculation in production rooms. One of the primary elements influencing the caliber of equipment installation, which includes ventilation provision, is the appropriate supply of air exchange.

The multiplicity of air exchange rates is utilized to increase the precision of the heat release calculation. A sufficient amount of air, dedicated to the production facility’s shop floor, enables you to guarantee hygienic working conditions and avoid equipment overheating.

Ventilation equipment for industrial premises

The components of the forced supply ventilation system are as follows:

• air ducts;
• fan;
• air filters;
• air dampers;
• air intake grilles
• Noise insulation;
• calorifier (air heating);
• automatic control unit if required.

With the exception of the calorifier and filters, which are not required for the removed air, the mechanical exhaust ventilation device is set up in accordance with the same model.

Industrial buildings’ local exhaust ventilation is set up using exhaust umbrellas, which are flexible ducts connected to the main air exchange system.

Furthermore, a heat recuperator can be added to the supply and exhaust ventilation systems to conserve energy while heating the incoming flow. Without interacting with it, the exhaust air’s heat is transferred to the supply air.

• Systemair ventilation – Danvent DV series
• Wolf ventilation

Design and installation

It is imperative to design and install ventilation early in the construction process to guarantee optimal performance. It is only possible to properly design the exhaust zones and consider all safety precautions in this manner.

However, it also occurs that a building that has already been built needs to have a ventilation system installed. In this instance, it is vital to consider the goal of the room in addition to all the circumstances under which the system will be used. The room’s potential for explosion and fire always influences the equipment selection.

Industrial buildings are known to use local ventilation and general exchange. The first one is in charge of the room’s overall air exchange and purification. However, local suction is limited to solving localized issues at the site of the hazardous material generation. However, such air flows cannot be entirely contained and neutralized to stop them from spreading throughout the space. It also needs other things, like umbrellas.

The type of production and the quantity of hazardous substances released, the dimensions of the room, and the intended temperature for the cold and warm seasons all have an impact on the equipment selection for the installation of ventilation in industrial spaces.

In conclusion I would like to emphasize that skilled professionals with years of experience and a wealth of knowledge should handle such challenging tasks as ventilation design, calculation, and installation.

Solution

An elaborate computation of the air flow rate in the convective flow rising above the cooker is shown below. Table 5 provides a summary of the findings from the calculations for the remaining kitchen appliances.

11.2.1 Diameter of a hydraulic pump We utilize the following formula () to determine the surfaces of the kitchen appliances:

11.2.2 The following formula () determines the kitchen equipment’s share of convective heat losses:

14,5–200-0,5-0,6 = 870 W is Qk.

11.2.3 The following formula () determines the air flow rate in the convective flow over the kitchen appliances at the level of local suction:

Lki is equivalent to 0,005-8701/3-(1,1 + 1,7-0,747)5/3-1, or 0,201 m3/sec.

The formula () allows us to calculate the flow rate of air removed from the local suction.

Lo is equal to (1,25/0,8) – (0,201-3 + 0,056-2 + 0,203-2) = 1,750 m3/s or 6300 m3/h.

The room hot shop’s air exchange rate, 6300/(6-8-3) = 44 1/h, is higher than 20 1/h. Since general exchange exhaust is not necessary, Lv = 0 m3/h according to.

The airflow rate from nearby rooms is accepted at a rate of 60% of the air volume flow rate, which is Lc = 3780 m3/h. This airflow rate is eliminated by local suctions.

The formula () allows us to calculate the mass air flow rate that is supplied to the hot shop room.

Gn =Loρ – Lcρs =795 kg/sec or 6300 kg/h – 3780 kg/185 =

Where at too = 30 °C, ρ = 1.165 kg/m3;

At tc = 25 °С, ρc = 1,185 kg/m3.

11.2.4 The ventilation of the room containing the hot shop and sales area is resolved jointly if they are in direct communication with one another.

It is assumed that the temperature in the hot shop is 5 °C higher than outside (parameters A []), but not more than 27 °Ρ, and that it is 3 °Ρ higher in the sales area, but not more than 25 °Ρ, when calculating ventilation.

Each visitor should release 116 W of heat into the halls, including 30 W of latent heat from food.

A minimum of 40 m3/h of outdoor air is required for non-smoking halls and 100 m3/h for smokers; shops that are hot rooms but not smoking rooms must allow 100 m3/h of outdoor air per worker.

In order to identify the heat balance and account for heat losses and the requirement for regulation capacity of ventilation units, public catering enterprises should calculate their ventilation separately for the summer, transitional (tnar = 10 °Ρ), and winter periods.

During the winter, the supply air temperature ranges from 16 to 18 degrees Celsius.

The computations lead to the following conclusions:

– the air removal rate from the local suction, which in this calculation example was 6300 m3/h;

– mass air flow rate, which is equal to 6300-1,165 = 7340 kg/h and is supplied to make up for the air removed, as calculated (refer to 11.2.3).

The local air suction compensates for the volume of air removed.

Flow of up to 60% from the sales area within; in this case, we’ll use Lc = 6300-0,6 = 3780 m3/h or Gc = 3780-1,185 = 4479 kg/h (1,244 kg/s);

– Gpr = 7340 – 4479 = 2861 kg/h (0,795 kg/sec.) is the supply of the residual air from the separate air inlet.

The distribution of supply and overflow air is designed to offset the apparent heat losses in the hot shop room, W, caused by people Ql, lighting Qocv, and equipment Qob.

Based on the apparent heat emissions from the installed capacity of equipment () in 50% and simultaneity coefficient Co = 0.6 (), the value of Qob is calculated similarly to Qk:

Qob is equal to (14,5-200-3 + 5-35-2 + 9-330-2)×0,5-0,6 = 4500 W.

7 people times Ql = 7-100 = 700 W;

48-20 = 960 W is Qocv.

In a heated shop room, total heat gain:

It is believed that local suctions absorb the convective portion of the kitchen equipment’s heat emissions that are above the outside air temperature, allowing radiant heat to enter the space. The apparent heat losses of kitchen equipment are split into convective and radiant categories in a 1:1 ratio due to the lack of more accurate data.

Next, using the air supply provided by the air inlet unit and a temperature of tn = 22,6 °Ρ, we compute the temperature of the hot shop during the summer. Let’s create an energy equation that balances the room for this purpose:

Gprsr(tcuh – tn) + Gsr(tcuh – tc) equals Qavn.

Here, Gpr and Gc stand for the mass flow rate in kilograms per second of air supplied by a separate air inlet installation and cross-flow air, respectively;

Cp, or air’s specific heat capacity, is 1005 J/(kg-°C).

Which is below 27 °C and less than 5 °C above the outside air temperature by 26.4 – 22.6 = 3.8 °C. The computation is finished.

In order to maintain the setpoint temperature supply unit, it is necessary to decrease the crossflow air flow rate and increase the air flow rate supplied by a separate air supply unit when the temperature rises above the acceptable value. Β Should this prove insufficient, the air provided by the independent supply unit needs to be cooled in order to preserve the predetermined temperature of the room air.

Air mass balance:

4479 + 2861 kg/h = 7340.

Air exchange rate in the premises of public catering enterprises

№	Names of premises	Estimated air temperature, °С	Air exchange rate per hour
inflow	exhaust
1	Hall, serving room	16	According to the calculation, but not less than 30 m3/h per person.
2	Lobby, vestibule	16	2	–
3	Cooking store	16	3	2
4	Hot shop, confectionery baking room	5	According to calculation, but not less than 100 m3/h per person.
5	Centers: pre-preparation, cold, meat, poultry, fish, processing of greens and vegetables	18	3	4
6	Room of the production manager	18	2	–
7	Room for flour products and finishing of confectionery products, linen room	18	1	2
8	Bread cutting room, ice-cream preparation room, serving room, utility room	18	1	1
9	Washing room: tableware, kitchen utensils, vessels, containers	18	4	6
10	Director"s office, office, main cash desk, waiters", staff and storekeeper"s rooms	18	4	6
11	Dry food pantry, inventory pantry, wine and spirits pantry, beer storage room	12	–	1
12	Storerooms of vegetables, pickles, containers	5	–	2
13	Reception room	16	3	–
14	Engine room of air-cooled chambers with air-cooled units	By calculation	By calculation	By calculation
15	The same, with water-cooled units	–	3	4
16	Repair shops	16	2	3
17	Premises of public organizations	16	1	1
18	Cooled storage chambers:
meats	–	–
fish	-2	–	–
Dairy and fatty products, gastronomy products	2	–	–
semi-finished products, including high degree of readiness	–	–
vegetables, fruits, berries, beverages	4	4	4
confectionery products	4	–	–
wines and beverages	6	–	–
ice cream and frozen fruit	-15	–	–
food waste	5	–	10
19	Smoking room	16	–	10
20	Unloading rooms	10	According to calculation	By calculation

Notes: 1. The air temperatures listed in the table correspond to the design temperatures for heating systems in all of the rooms except for the cooled chambers.

2. Air multiplicity minus three is acceptable in buffets, bars, cocktail halls, and banquet halls that are situated in distinct rooms.

3. Throughout the year, the refrigerated chambers are kept at the air temperatures listed in the table, seven days a week. Meat and fish or meat and fish semi-finished products are stored in chambers at ±0 °C; vegetable semi-finished products are stored at +2 °C; and all products are stored in one chamber within the enterprise at ±2 °C.

Climatic equipment for offices

• Supply ventilation unit for office. Blows fresh air from the street directly into the office space. The air is displaced into corridors and lobbies. When the floor area is more than 40 sq. The air is evacuated directly from it. Supply units for office ventilation are used for areas up to 100 square meters. meters;
• Supply and exhaust office ventilation systems. This is the most widely used type of equipment, providing outflow, purification and delivery of air. The set may include cooling or heating devices, humidifiers. There is a wide variety of equipment, but the supply and exhaust ventilation of the office should be calculated and installed by professionals. Automatic control over functionality reduces energy consumption and increases efficiency;
• Duct ventilation system in an office. Duct air conditioners with air supply from the street are installed in offices of small and medium area. Combined with supply and exhaust equipment, bringing the temperature of street air to the required temperature. After which it is supplied to the rooms;
• Central air conditioning and ventilation in a large office building. In large office buildings climate controlled by chiller-fancoil systems and multi-zone VRF systems. The latter consist of a number of indoor units providing different temperature and humidity in the rooms. Central air conditioners are supply and exhaust ventilation in offices with cooling and heating units. This type of climate systems is suitable for large offices that are not divided into separate rooms.

Normative documents and calculation of air circulation

The STOs, Building Rules, and TB regulations that apply to the specific plant control the air exchange ratio in a building. SanPiN 2.2.4.548-96 governs the standards for hygiene and sanitation in production facilities.

Methodological recommendations for air circulation calculations.

The formula for air mass exchange is as follows:

Where n is a number representing the multiplicity of air exchange and L is the volume of incoming air in m3/h; S is the object’s area in square meters; H is its height in meters.

Up to three or four times an hour, the number of multiples increases in natural ventilation conditions. Merely using mechanical ventilation, this parameter is raised.

The formula below establishes the design parameters for the exhaust ventilation of production facilities:

When it comes to curved slopes D=d+0,8z

Where d is the diameter and a×b are the emission source’s dimensions. The air movement rate where the air is extracted is represented by ̲v, the suction velocity in the umbrella’s vicinity by ̲z, and the installation height by z.

Production halls

Heat energy and dangerous materials are frequently present in the workspaces of retail establishments. Production shop air exchange standards are outlined in SNiP 41-01-2003.

The following formula is used to determine the shop ventilation values:

Where L is the air flow rate in m³, V is the unit’s air flow velocity in m/s, and S is the area measured in m² by the installed hood’s opening.

The following factors determine the production rooms’ air turnover values:

1. area and shape of the shop;
2. the number of personnel;
3. The intensity of people"s physical activity;
4. production technology;
5. heat losses of the equipment;
6. increased humidity in the shop.

Emissions of dust and harmful substances

Hazardous emissions can take the form of heat emissions, mechanical dust, or chemical vapors, depending on the workflow of production shops.

The operating scheme and capacity of exhaust devices can vary. Additional exhaust ventilation with a ten-fold exchange rate over general ventilation should be installed in the event of an accident and sudden, large-scale release of toxic vapors and gases within the production premises.

In the event of an accident, it is important to turn on the ventilation systems both inside and outside the building. This will quickly lower the amount of toxic gases present and eliminate hazardous waste that has become vaporized at the work locations.

Ventilation of warehouse complexes

The presence of ventilation in warehouses guarantees the protection of goods kept within from external hazards. Warehouse complexes have heat and dust emissions on their property. Hazardous gas emissions could be present if dangerous materials are kept there.

The "SNiP 41-01-2003. Heating, ventilation, and air conditioning" section of SP 60.13330.2012 governs the ventilation standards for buildings housing warehouses.

In warehouse buildings, exhaust structures are typically located in the dirtiest areas.

Here’s how the air exchange rate is calculated:

Where V(m³) is the storage room’s volume and A(m³/h) is the air volume released in the warehouse over the course of an hour.

Calculate the flow rate by heat release

The following formula is used to determine the amount of excess heat (kJ/h) removed from the storage room:

Where Qotd. is the amount of heat emitted into the environment in kJ/h; Q_n is the amount of heat energy released into the room by the working people and equipment.

The following formula can be used to determine the quantitative air parameter (in m³/h) required for removal for one hour, assuming there are heat losses:

Where K is the temperature difference between the incoming and outgoing air; ΔT is the air mass’s heat capacity, expressed as K; and γpr, or the supply air’s density, is expressed as γpr = 1,29 kg/m³.

When dangerous gases or dust are present, L is determined for each situation individually.

The following formula is used to determine the multiplicity by heat release:

Norms SNIP for residential premises

Human activity causes the amount of carbon dioxide in the air, the temperature of the air, and the humidity in residential areas to rise. Odors that are unpleasant are also frequently detected and are brought on by dust collecting on different components of living rooms.

In this instance, the entire volume of air that contains hazardous materials must be extracted from the room and replaced with fresh air. Therefore, the following conditions are assumed for the ventilation requirement in residential spaces:

1. The percentage of carbon dioxide in the air of the room should be within the range of 0.07 to 0.1 %.
2. The living space should be supplied with 30-40 cubic meters of fresh air per hour per adult and 12 to 30 cubic meters per child.
3. Temperature jumps are not allowed in the room, so the deviation from the normal value should not be more than 3-5%.
4. Humidity also needs to be within the normal range. However, its values are different for all rooms in the residential structure.

Sanitary requirements

You must become familiar with the specifications of SNiP 31-01-2003 and SP 60.13330.2012 in order to determine the volume of air for ventilation that it should supply to the room and, conversely, remove from it. The first document lays out the hygienic specifications for residential buildings’ ventilation systems.

Two categories of parameters are used in SNiP calculations: air volume flow rate per unit of time (cu. m.). m/hour) and hourly multiplicity, which measures the number of times a room undergoes a complete air exchange cycle in a given hour. These specifications are determined by the room’s intended use:

• 1 time/hour – bedroom, children"s living room;
• 25 cube. м./hour – toilet, bathroom;
• 60 cubic meters. м./hour – kitchen with electric stove;
• 1 time/hour + 100 cc. м./hour – kitchen with a gas stove, furnace room with a solid fuel boiler;
• 90cc. м./hour – room for washing and dryer;
• 0.2 times/hour – utility rooms (checkroom, pantry, etc.) – the humidity should also be kept to a minimum.);
• 0.5 times/hour – office, library;
• 3 times/hour + V of air for combustion – boiler houses equipped with a heat generator on natural gas.

SNiP reduces the ventilation load in the room when all of the equipment is off and no one is present. In living rooms and technical rooms, for instance, the hourly multiplicity is decreased to a coefficient of 0.2 and 0.5, respectively. The location of installed gas equipment is an exception. The exhaust volume and the inlet volume need to match, according to SNiP.

Much simpler ventilation requirements in accordance with SP 60.13330.2012. The number of individuals staying in the room for longer than two hours determines the parameters of the necessary air exchange:

• If there is more than 20 square meters per one family member in a residential apartment, the volume of the boiler room should be more than 20 square meters. m, the ventilation system should provide for each resident 30 cu.m./hour – toilets, bathrooms, toilets, bathrooms and technical rooms. m/h of fresh air.
• When there is less than 20 square meters of apartment area per one occupant, the volume of supply air can be calculated by area – 3 cubic meters. m/h per 1 sq. m. м.
• In the absence of opening windows and openings in the apartment, ventilation should provide 60 cubic meters of air per hour. m/h of clean air per person, regardless of the total floor area of the dwelling.

The regulations’ requirements do not conflict with one another, despite their slight variations. SNiP norms are followed in the preliminary computations. The acquired results are compared to SP’s requirements. Modifications to the parameters are made as needed.

Ventilation of the repair shop

One oddity is the intense, uneven release of welding aerosols in some places. It is impossible to arrange local exhausts when fixing large machinery or equipment. The repair and maintenance unit’s heat supply might also be restricted.

The workshop’s ventilation plan is drawn taking into account all relevant variables. Local climate zones of a given structure can be arranged. At the height of accumulated welding smoke, air ducts are installed to allow for the filtering and discharge of air flow. Air circulation is created on the opposite side by supplying the cleaned supply air above the working area, which is supplemented with fresh air mass.

When it comes to heating and insulating your house, comfort and energy efficiency are the primary concerns. You can drastically cut down on heat loss in the winter and keep your house cool in the summer by caulking up any air leaks and properly insulating your walls, floors, and attic. Furthermore, keeping adequate ventilation is necessary to avoid moisture buildup, which can result in mold and other problems, and to maintain high indoor air quality. You and your family can live in a comfortable, healthful, and energy-efficient home by finding the ideal balance between insulation and ventilation.

Sanitary norms of design of industrial enterprises

As per the guidelines set forth by SNiP, any adverse factors, including heat and moisture, that are released within industrial premises are subtracted from the technological part of the design documentation’s calculations.

Based on naturally gathered facts from the study, it is permitted to take the amount of production harmful substances emitted in the room if such data are not available in the technological norms of design. The passport documents pertaining to the specialized equipment that was purchased also specify the necessary value.

Toxic substances are released into the area through both concentrated and dispersed general ventilation system devices.

The amount of substances released must be calculated so that it does not exceed:

1. Maximum value for the city and settlements.
2. Indicators of the maximum amount in the air, which penetrates into the interior of residential buildings through windows on the principle of natural ventilation, (30% of the norm of the established limit of the amount of concentration of harmful, toxic substances in the working area).

As part of the enterprise’s ventilation project, the dispersion coefficient of toxic elements that are in the system at the time of emission is determined. Therefore, in accordance with the standards, the process of supplying outdoor air must be considered in industrial premises, so long as the air volume per subject is 20 m3. Thus, it should be a maximum of 30 m3h for every individual occupying the space. However, if the volume of air per person exceeds 20 m3, each subject should receive at least 20 m3h of air from the outside.

When creating a project of the working zone of industrial production purposes, in which there is no natural ventilation, while with the supply of outside air into them only by means of existing mechanical ventilation, the total amount of air should be at least 60 m3 / h per subject. The indicator can vary within the tabulated data, but should not be less than one multiple of the air exchange rate per hour.

The amount of outdoor flow for a single subject may be less than 60 m3 per hour if the computed rate of air exchange is lower than the tabulated rate and recirculation is employed, but it should not be less than 15-20% of the system’s overall air exchange flow.

Maintaining a safe and productive work environment requires an understanding of the significance of air exchange rates in industrial settings. It has an immediate effect on worker well-being, operational efficiency, and equipment longevity. Businesses can guarantee the best possible air quality and energy efficiency in their facilities by following established standards and guidelines, like those found in SNiPs (Construction Norms and Regulations).

The ability of air exchange rate tables to offer precise guidelines suited to different industrial settings is one of its main advantages. These tables account for various factors, including the number of occupants, the size of the space, and the type of activity being conducted. These tables help businesses identify the right amount of ventilation for their particular needs, maximizing worker safety and comfort and reducing energy waste.

Furthermore, following SNiPs and other regulations helps businesses avoid possible legal and financial ramifications in addition to encouraging a healthier work environment. Ventilation regulations must be followed in order to avoid penalties, legal action, and in extreme circumstances, shutdowns. Consequently, it is both a matter of corporate responsibility and wise business practice to invest in appropriate ventilation systems and to routinely monitor air exchange rates.

To sum up, it is critical to maintain sufficient air exchange rates in industrial buildings in order to support worker well-being, guarantee operational effectiveness, and adhere to legal requirements. Businesses can minimize energy costs and stay out of trouble by using air exchange rate tables and adhering to the guidelines outlined in SNiPs to create a safer, healthier, and more productive work environment. Setting up adequate ventilation as a top priority is a smart investment in the long-term viability of the company, not just a compliance requirement.

Video on the topic

Heat loss for ventilation. Simple calculation / Gleb Green

Industrial ventilation \ Leutin Engineering \ Brief report from the site \ Industrial ventilation

Ventilation of industrial premises

What is air exchange. Air exchange rate

How to determine the minimum air quantity? Manipulation of Building Regulations

How to calculate the CREATIVITY of air exchange

VENTILATION / AIR EXCHANGE CNC SNP GOST / IMVENT / VENTILATION SYSTEM EFFICIENCY