Date: 12/12/2015
Boilers make a lot of noise. They have many elements that make sounds: these are pumps, fans, pumps and other mechanisms. In principle, work in industry, with industrial equipment, one way or another forces a specialist to deal with noise, and there is no way to make the units completely silent yet. But you can make them pretty much less loud.
How to reduce the noise of the boiler room when designing
Very strict requirements are imposed on the noise level of electric and thermal power facilities, especially if the designated facilities are located within the city. A boiler room is just an object of heat power engineering, and even being compact, it can cause significant discomfort to others.
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Advantages and disadvantages of a mini-boiler house in an apartment building
Energy resources are becoming more expensive - this is a fact, therefore, the issue of saving energy resources has become especially acute in recent times. This also applies to the heating systems of apartment buildings. The cost directly depends on the method of supplying heat to residents, of which there are currently two: centralized and autonomous.
Sources of general vibration are rotating mechanisms - a smoke exhauster, a fan and pumps, as well as a working boiler. Vibration occurs both with poor centering or imbalance of rotating mechanisms, and in the case of proper balancing. In equipment, vibration occurs when the medium moves.
Vibration can cause disturbance of body functions. Under the influence of general vibration, changes occur in the central nervous system: dizziness, tinnitus, drowsiness, coordination of movements is disturbed. From the side of the cardiovascular system, instability of blood pressure, hypertensive phenomena are observed. The defeat of the skin-articular apparatus is localized in the legs and spine. At high intensity and in a certain frequency range - tissue rupture. The most dangerous for the human body are vibrations whose frequencies coincide with the frequencies of natural vibrations of the human body and its internal organs, since such vibrations can cause resonant phenomena in the body. The frequency range of such vibrations is from 4 to 400 Hz. The most dangerous frequency is 5¸9 Hz.
The vibration in the boiler room is constant.
The operator of the boiler room is affected by the general vibration of category 3, technological type A (at permanent workplaces of industrial premises of enterprises).
The main document on vibration is SN 2.2.4/2.1.8.566-96 "Industrial vibration, vibration in premises of residential and public buildings".
When normalizing vibrations, deviations of the vibration velocity and vibration acceleration from the maximum allowable values along the axes of the orthogonal coordinate system are taken into account.
The main way to ensure vibration safety should be the creation and use of vibration-proof machines. When designing and using machines, buildings, objects, methods should be used that reduce vibration along the paths of its propagation from the excitation source; applied vibration isolation, vibration-damping bases (pneumatic dampers, springs).
To exclude vibrations and shocks from the operation of machines, the supporting structures of the building should not come into contact with the foundations of the machines.
Vibration-damping foundations are used in the boiler house on the foundations of the pumps.
The sources of noise in the boiler room are the boiler, operating pumps, smoke exhauster, fan, movement of water and steam in pipelines.
Intense noise during daily exposure reduces hearing acuity, leads to a change in blood pressure, weakens attention, reduces visual acuity, accelerates the process of fatigue, causes a change in the motor centers. Noise has a particularly adverse effect on the cardiovascular and nervous systems. Noise with an intensity of more than 130 dB causes pain in the ears, and at 140 dB, irreversible hearing damage occurs.
A characteristic of constant noise at workplaces is sound pressure levels in octave bands with geometric mean frequencies of 31.5, 63, 125, 250, 500, 1000, 2000, 4000, 8000 Hz.
A characteristic of intermittent noise at workplaces is an integral criterion - the equivalent (in terms of energy) sound level.
The noise in the boiler room is constant broadband.
The main document on noise exposure SN 2.2.4 / 2.1.8.562-96 "Noise at workplaces, in the premises of residential, public buildings and in residential areas."
Permissible sound pressure levels in octave frequency bands, sound levels and equivalent sound levels at workplaces should be taken:
For broadband constant and non-constant (except for impulse) noise - according to Table. 13.4;
For tonal and impulse noise - 5 dB less than the values \u200b\u200bspecified in Table. 14.4.
Table 14.4
Permissible sound pressure levels at workplaces and on the territory of enterprises
When developing technological processes, designing, manufacturing and operating machines, industrial buildings and structures, as well as organizing a workplace, all necessary measures should be taken to reduce noise affecting a person at workplaces to values not exceeding the permissible values in the following areas:
Development of noise-safe equipment;
The use of means and methods of collective protection in accordance with GOST 12.1.029-80 “SSBT. Means and methods of noise protection. Classification";
The use of personal protective equipment in accordance with GOST 12.4.011-89 “Protection equipment for workers. Basic requirements and classification”.
Zones with a sound level or an equivalent sound level above 80 dBA must be marked with safety signs in accordance with GOST R 12.4.026-2001 “SSBT. Signal colors and safety signs. Those working in these areas must be provided with personal protective equipment.
One of the methods to reduce noise is to reduce the noise in its path. It is implemented by the use of casings, screens and soundproof partitions that cover the above equipment, the use of soundproofing of building envelopes; sealing around the perimeter of the porches of windows, gates, doors; soundproofing of the intersections of enclosing structures with engineering communications; soundproofed observation and remote control booths. Earmuffs and earmuffs are used as personal protective equipment.
To reduce noise from rotating mechanisms in the boiler room, casings are used. The operator room is soundproofed.
Sound insulation of a boiler room. In this publication, we will consider the causes of increased noise and vibration levels from gas boilers and boiler rooms, as well as ways to eliminate them in order to achieve standard indicators and the level of comfort of residents.
The installation of autonomous modular gas boilers on the roofs of apartment buildings is becoming increasingly popular among developers. The advantages of such a boiler house are obvious. Among them
No need to erect a separate building for boiler room equipment
Reduction of heat losses by 20% due to the small number of heating mains in comparison with heating from the central heating network
Savings on the installation of communications from the coolant to the consumer
No need for forced ventilation
The possibility of full automation of the system with a minimum of staff
One of the disadvantages of a rooftop boiler is vibrations from the boiler and pumps. As a rule, they are the result of shortcomings in the design, construction and installation of boiler room equipment. Therefore, the responsibility for eliminating the increased noise level and soundproofing the boiler room lies with the developer or housing management company.
The noise from the boiler house is low-frequency and is transmitted through the structural elements of the building directly from the source and through communications. Its intensity in a room equipped for a boiler room is 85-90dB. Noise insulation of a rooftop boiler room is justified if it is produced from the source side, and not in the apartment. Soundproofing the ceiling and walls in an apartment with such noise is expensive and ineffective.
Causes of increased noise level in the rooftop boiler room.
Insufficient thickness and massiveness of the base on which the boiler room equipment stands. This leads to the penetration of airborne noise into the apartments through the floor slab and the technical floor.
Lack of proper vibration isolation of the boiler. At the same time, vibrations are transmitted to ceilings and walls, which radiate sound into apartments.
Rigid fastening of pipelines, communications and their supports is also a source of structural noise. Normally, pipes should pass through building envelopes in an elastic sleeve, surrounded by a layer of sound-absorbing material.
Insufficient thickness of the pipeline, as a design error, leading to high water velocity and the creation of an increased level of hydrodynamic noise.
Soundproofing of the rooftop boiler room. List of events.
Installation of vibration isolating supports under the equipment of the boiler room. The calculation of materials for vibration isolation is made taking into account the area of \u200b\u200bthe support and the weight of the equipment;
Elimination of "hard connections" in the places of fastening of pipeline supports with the help of material silomer, thermosound insulation or installation of vibration fasteners on studs fixing communications;
In the absence of elastic sleeves, expansion of the pipeline passage through the supporting structures, wrapping with elastic material (k-flex, vibrostack, etc.) and a heat-resistant layer (basalt cardboard);
Wrapping the pipeline with a material that reduces heat loss and has sound insulation properties: , Texound 2ft AL;
Additional sound insulation of enclosing structures of the roof boiler room;
Installation of rubber compensators to reduce the transmission of vibrations through the pipeline;
Installation of silencers in the exhaust gas duct;
Installation of noise-absorbing materials based on basalt (Stopsound BP) or fiberglass (Acustiline fiber) allows you to reduce background noise in the boiler room by 3-5dB.
SOUND INSULATION OF A BOILER IN A WOODEN HOUSE.
Building codes and fire safety regulations dictate the installation of the boiler in a special room equipped with a separate entrance. As a rule, it is located in the basement or basement. With this arrangement, complaints about an increased noise level from the boiler are rare.
A boiler installed on the same floor with living rooms, which has a high noise level with complete silence in a country house, can cause inconvenience to residents. Therefore, the soundproofing of the boiler may be relevant.
The reasons for the increased noise level can be similar to those of a rooftop boiler, but on a smaller scale. They also include
Features of the design of the outer box of the boiler. In most models of boilers, the burner and fan are closed with a separate damper, which reduces the noise produced by the burner. If the only soundproofing protection is the plastic box of the boiler, the noise from the burner can be noticeable.
Noisy fan from the manufacturer.
Unbalance of the fan, dirt sticking due to dust from outside and neglect of maintenance measures.
Air entering the heating system.
Incorrect gas burner setting.
Rigid system for fastening the boiler and outlet pipes.
The soundproofing of the boiler begins with identifying the causes of the increased noise level and is associated with the work of the gas service employees serving it or the company involved in soundproofing the premises.
If the operation of the boiler and the system is adjusted, then
We mount the boiler on a vibration-isolated platform on mounts with a force meter
We install rubber compensators in the places where the pipes exit from the boiler body
We purchase a noise-protective casing for the boiler
We make additional soundproofing of the walls of the boiler room
To reduce background noise in the boiler room
Welcome to the Comfort Zone!
Russian Ministry of Health
Moscow
1. Developed by the Research Institute of Occupational Medicine of the Russian Academy of Sciences (Suvorov G.A., Shkarinov L.N., Prokopenko L.V., Kravchenko O.K.), Moscow Research Institute of Hygiene. F.F. Erisman (Karagodina I.L., Smirnova T.G.).
2. Approved and put into effect by the Decree of the State Committee for Sanitary and Epidemiological Supervision of Russia dated October 31, 1996 N 36.
3. Introduced instead of "Sanitary norms for permissible noise levels at workplaces" N 3223-85, "Sanitary norms for permissible noise in the premises of residential and public buildings and on the territory of residential development" N 3077-84, "Hygienic recommendations for establishing noise levels at workers places, taking into account the intensity and severity of labor "N 2411-81.
APPROVED
Decree of the State Committee for Sanitary and Epidemiological Supervision
Russia dated October 31, 1996 N 36
Date of introduction since approval
1. Scope and general provisions
1.1. These sanitary norms establish the classification of noise; normalized parameters and maximum permissible noise levels at workplaces, permissible noise levels in the premises of residential, public buildings and in residential areas.
1.2. Sanitary standards are mandatory for all organizations and legal entities on the territory of the Russian Federation, regardless of the form of ownership, subordination and affiliation, and individuals, regardless of citizenship.
1.3. References and requirements of sanitary standards should be taken into account in the State standards and in all regulatory and technical documents regulating planning, design, technological, certification, operational requirements for production facilities, residential, public buildings, technological, engineering, sanitary equipment and machines, vehicles, household appliances.
1.4. Responsibility for fulfilling the requirements of the Sanitary Norms is assigned in the manner prescribed by law to the heads and officials of enterprises, institutions and organizations, as well as citizens.
1.5. Control over the implementation of the Sanitary Standards is carried out by the bodies and institutions of the State Sanitary and Epidemiological Supervision of Russia in accordance with the Law of the RSFSR "On the Sanitary and Epidemiological Welfare of the Population" dated April 19, 1991 and taking into account the requirements of the current sanitary rules and norms.
1.6. Measurement and hygienic assessment of noise, as well as preventive measures should be carried out in accordance with the guideline 2.2.4 / 2.1.8-96 "Hygienic assessment of the physical factors of the production and environment" (under approval).
1.7. With the approval of these sanitary standards, the “Sanitary standards for permissible noise levels at workplaces” N 3223-85, “Sanitary standards for permissible noise in the premises of residential and public buildings and on the territory of residential development” N 3077-84, “Hygienic recommendations for setting levels noise at workplaces, taking into account the intensity and severity of labor "N 2411-81.
2.1. Law of the RSFSR "On the sanitary and epidemiological well-being of the population" dated 19.04.91.
2.2. Law of the Russian Federation "On Environmental Protection" dated 12/19/91.
2.3. Law of the Russian Federation "On Protection of Consumer Rights" dated 07.02.92.
2.4. Law of the Russian Federation "On certification of products and services" dated 10.06.93.
2.5. "Regulations on the procedure for the development, approval, publication, implementation of federal, republican and local sanitary rules, as well as on the procedure for the operation of all-Union sanitary rules on the territory of the RSFSR", approved by Resolution of the Council of Ministers of the RSFSR of 01.07.91 N 375.
2.6. Decree of the State Committee for Sanitary and Epidemiological Supervision of Russia "Regulations on the procedure for issuing hygienic certificates for products" dated 05.01.93 N 1.
3. Terms and definitions
3.1. Sound pressure is a variable component of air or gas pressure resulting from sound vibrations, Pa.
3.2. Equivalent / energy / sound level, LA.eq., dBA, intermittent noise - the sound level of constant broadband noise, which has the same RMS sound pressure as this intermittent noise for a certain period of time.
3.3. The maximum permissible level (MPL) of noise is the level of a factor that, during daily (except weekends) work, but not more than 40 hours a week during the entire working experience, should not cause diseases or deviations in the state of health detected by modern research methods in in the process of work or in the remote periods of life of the present and subsequent generations. Compliance with the noise limit does not exclude health problems in hypersensitive individuals.
3.4. The permissible noise level is the level that does not cause significant concern to a person and significant changes in the indicators of the functional state of noise-sensitive systems and analyzers.
3.5. Maximum sound level, LА.max., dBA - the sound level corresponding to the maximum indicator of a measuring, direct-reading instrument (sound level meter) during visual reading, or the sound level value exceeded for 1% of the measurement time during registration by an automatic device.
4. Classification of noise affecting a person
4.1. According to the nature of the noise spectrum, there are:
- broadband noise with a continuous spectrum more than 1 octave wide;
- tonal noise, in the spectrum of which there are pronounced tones. The tonal nature of the noise for practical purposes is established by measuring in 1/3 octave frequency bands by exceeding the level in one band over the neighboring ones by at least 10 dB.
4.2. According to the temporal characteristics of noise, there are:
- constant noise, the sound level of which during an 8-hour working day or during the measurement time in the premises of residential and public buildings, on the territory of residential development changes in time by no more than 5 dBA when measured on the time characteristic of the sound level meter “slowly”;
- intermittent noise, the level of which during an 8-hour working day, work shift or during measurements in the premises of residential and public buildings, on the territory of residential development changes over time by more than 5 dBA when measured on the time characteristic of the sound level meter "slowly".
4.3. Intermittent noises are divided into:
- time-varying noise, the sound level of which changes continuously over time;
- intermittent noise, the sound level of which changes stepwise (by 5 dBA or more), and the duration of the intervals during which the level remains constant is 1 s or more;
- impulse noise consisting of one or more audio signals, each of less than 1 s duration, while the sound levels in dBAI and dBA, measured respectively on the “impulse” and “slow” time characteristics, differ by at least 7 dB.
5. Normalized parameters and maximum permissible noise levels at workplaces
5.1. Characteristics of constant noise at workplaces are sound pressure levels in dB in octave bands with geometric mean frequencies of 31.5; 63; 125; 250; 500; 1000; 2000; 4000; 8000 Hz, determined by the formula:
Where P is the root mean square value of sound pressure, Pa;
P0 is the initial value of the sound pressure in the air equal to 2 10-5Pa.
5.1.1. It is allowed to take as a characteristic of constant broadband noise at workplaces the sound level in dBA, measured on the “slow” time characteristic of the sound level meter, determined by the formula:
Where RA is the root mean square value of the sound pressure, taking into account the correction "A" of the sound level meter, Pa.
5.2. A characteristic of intermittent noise at workplaces is the equivalent (in terms of energy) sound level in dBA.
5.3. Maximum permissible sound levels and equivalent sound levels at workplaces, taking into account the intensity and severity of labor activity.
A quantitative assessment of the severity and intensity of the labor process should be carried out in accordance with Guideline 2.2.013-94 "Hygienic criteria for assessing working conditions in terms of harmfulness and danger of factors in the working environment, severity, intensity of the labor process."
6. Rated parameters and permissible noise levels in the premises of residential, public buildings and residential areas
6.1. Normalized constant noise parameters are sound pressure levels L, dB, in octave bands with geometric mean frequencies: 31.5; 63; 125; 250; 500; 1000; 2000; 4000; 8000 Hz. For an approximate assessment, it is allowed to use sound levels LA, dBA.
6.2. The normalized parameters of intermittent noise are equivalent (in terms of energy) sound levels LAeq, dBA, and maximum sound levels LAmax, dBA.
Evaluation of non-permanent noise for compliance with permissible levels should be carried out simultaneously on the equivalent and maximum sound levels. Exceeding one of the indicators should be considered as non-compliance with these sanitary standards.
6.3. Permissible values of sound pressure levels in octave frequency bands, equivalent and maximum sound levels of penetrating noise in the premises of residential and public buildings and noise in residential areas.
Bibliography
- Guideline 2.2.4 / 2.1.8.000-95 "Hygienic assessment of the physical factors of the production and environment."
- Guideline 2.2.013-94 "Hygienic criteria for assessing working conditions in terms of harmfulness and danger of factors in the working environment, severity, intensity of the labor process."
- Suvorov G. A., Denisov E. I., Shkarinov L. N. Hygienic regulation of industrial noise and vibrations. — M.: Medicine, 1984. — 240 p.
- Suvorov G. A., Prokopenko L. V., Yakimova L. D. Noise and health (environmental and hygienic problems). - M: Soyuz, 1996. - 150 p.
- Permissible levels of noise, vibration and sound insulation requirements in residential and public buildings. MGSN 2.04.97 (Moscow city building codes). - M., 1997. - 37 p.
The number of appeals from citizens received by the Office of Rospotrebnadzor in the Tyumen region about the deterioration of living conditions due to exposure to excess noise levels is increasing every year.
In 2013, 362 appeals were received (in total for violations of peace and quiet, accommodation and noise), in 2014 - 416 appeals, in 2015 80 appeals have already been received.
According to the established practice, after the request of residents, the Department appoints measurements of noise and vibration levels in a residential building. If necessary, measurements are carried out in organizations located near apartments, where, for example, “noisy” equipment is used - a source of noise (restaurant, cafe, shop, etc.). If noise and vibration levels are found to exceed the permissible values, in accordance with SN 2.2.4/2.1.8.562-96 "Noise at workplaces, in residential, public buildings and on the territory of residential development", to the owners of noise sources - legal entities, individual entrepreneurs - the Department issues an order to eliminate the identified violations of sanitary legislation.
How can the noise from the equipment listed above be reduced so that there are no complaints from the residents of the house during its operation? Of course, the ideal option is to provide for the necessary measures at the design stage of a residential building, then the development of noise reduction measures is always possible, and their implementation during construction is ten times cheaper than in those houses that have already been built.
The situation is quite different if the building has already been built and there are noise sources in it that exceed the current standards. Then, most often, noisy units are replaced with less noisy ones and measures are taken to isolate the units and the communications leading to them. Next, we will look at specific sources of noise and vibration isolation measures for equipment.
NOISE FROM THE AIR CONDITIONER
The use of three-link vibration isolation, when the air conditioner is installed on the frame through a vibration isolator, and the frame - on a reinforced concrete slab through rubber gaskets (in this case, the reinforced concrete slab is installed on spring vibration isolators on the roof of the building), leads to a decrease in penetrating structural noise to levels permissible in residential premises.
To reduce noise, in addition to strengthening the noise and vibration isolation of the air duct walls and installing a silencer on the air duct of the ventilation unit (from the side of the premises), it is necessary to fasten the expansion chamber and air ducts to the ceiling through vibration isolating hangers or gaskets.
NOISE FROM THE BOILER ROOM ON THE ROOF
To protect against the noise of the boiler house located on the roof of the house, the foundation plate of the roof boiler house is installed on spring vibration isolators or a vibration isolation mat made of special material. The pumps and boiler units equipped in the boiler room are installed on vibration isolators and soft inserts are used.
The pumps in the boiler room must not be placed with the motor downwards! They must be mounted in such a way that the load from the pipelines is not transferred to the pump housing. Along with this, the noise level is higher from a pump with a higher power or if several pumps are installed. To reduce noise, the foundation plate of the boiler room can also be placed on spring dampers or high-strength multilayer rubber and rubber-metal vibration isolators.
The current regulations do not allow the placement of a roof boiler directly on the ceiling of residential premises (the ceiling of a residential premises cannot serve as the base of the boiler room floor), as well as adjacent to residential premises. It is not allowed to design roof boiler houses on the buildings of preschool and school institutions, medical buildings of polyclinics and hospitals with round-the-clock stay of patients, on the sleeping buildings of sanatoriums and recreation facilities. When installing equipment on roofs and ceilings, it is desirable to place it in places farthest from the protected objects.
NOISE FROM INTERNET EQUIPMENT
According to the recommendations for the design of communication systems, informatization and dispatching of housing construction objects, it is recommended to install cellular antenna amplifiers in a metal cabinet with a locking device on technical floors, attics or stairwells of upper floors. If it is necessary to install house amplifiers on different floors of multi-storey buildings, they should be installed in metal cabinets in the immediate vicinity of the riser under the ceiling, usually at a height of at least 2 m from the bottom of the cabinet to the floor.
When installing amplifiers on technical floors and attics, to eliminate the transmission of vibration of a metal cabinet with a locking device, the latter must be installed on vibration isolators.
OUTPUT - VIBRATION ISOLATORS AND FLOATING FLOORS
For ventilation, refrigeration equipment on the upper, lower and intermediate technical floors of residential buildings, hotels, multifunctional complexes or in the vicinity of noise-rated rooms where people constantly stay, you can install the units on factory vibration isolators on a reinforced concrete slab. This slab is mounted on a vibration-isolated layer or springs on a "floating" floor (an additional reinforced concrete slab on a vibration-isolation layer) in a technical room. It should be noted that fans, outdoor condensing units, which are now produced, are equipped with vibration isolators only at the request of the customer.
"Floating" floors without special vibration isolators can only be used with equipment that has an operating frequency of more than 45-50 Hz. These are, as a rule, small machines, the vibration isolation of which can be provided in other ways. The efficiency of floors on an elastic foundation at such low frequencies is low, therefore they are used exclusively in combination with other types of vibration isolators, which provides high vibration isolation at low frequencies (due to vibration isolators), as well as at medium and high frequencies (due to vibration isolators and a “floating” floor). ).
The floating floor screed must be carefully isolated from the walls and the supporting floor slab, since the formation of even small rigid bridges between them can significantly impair its vibration isolation properties. In places where the "floating" floor adjoins the walls, there must be a seam of non-hardening materials that does not allow water to pass through.
NOISE FROM THE GARBAGE DUCT
To reduce noise, it is necessary to comply with the requirements of the norms and not design the trunk of the garbage chute adjacent to residential premises. The trunk of the garbage chute should not adjoin or be located in the walls enclosing residential or service premises with normalized noise levels.
The most common measures to reduce noise from garbage chutes are as follows:
- in the premises for collecting garbage, a “floating” floor is provided;
- with the consent of the residents of all apartments in the entrance, the garbage chute is welded (or liquidated) with the placement of wheelchair garbage chambers, concierge rooms, etc. in the room. (the positive point is that in addition to noise, odors disappear, the possibility of rats and insects, the likelihood of fires, dirt, etc. is eliminated);
- the loading valve bucket is mounted with framed rubber or magnetic seals;
- decorative heat and noise protective lining of the waste chute shaft made of building materials is separated from the building structures of the building with soundproof gaskets.
Today, many construction companies offer their services, various designs to increase the sound insulation of walls and promise complete silence. It should be noted that in fact, no structures can remove structural noise transmitted through the floors, ceilings and walls when dumping municipal solid waste into the garbage chute.
NOISE FROM ELEVATORS
In SP 51.13330.2011 “Noise protection. Updated edition of SNiP 23-03-2003 ”it is said that it is advisable to place elevator shafts in the stairwell between flights of stairs (clause 11.8). In the architectural and planning solution of a residential building, it should be provided that the built-in elevator shaft adjoins premises that do not require increased protection against noise and vibration (halls, corridors, kitchens, sanitary facilities). All elevator shafts, regardless of the planning solution, must be self-supporting and have an independent foundation.
Shafts should be separated from other building structures with an acoustic joint of 40-50 mm or vibration-isolating pads. As the material of the elastic layer, slabs of acoustic mineral wool on a basalt or fiberglass base and various foamed polymeric roll materials are recommended.
To protect against structural noise of an elevator installation, its drive motor with a gearbox and a winch, usually mounted on one common frame, is vibration isolated from the supporting surface. Modern elevator drive units are equipped with appropriate vibration isolators installed under metal frames, on which motors, gearboxes and winches are rigidly mounted, and therefore additional vibration isolation of the drive unit is usually not required. At the same time, it is additionally recommended to make a two-stage (two-link) vibration isolation system by installing the support frame through vibration isolators on a reinforced concrete slab, which is also separated from the floor by vibration isolators.
The operation of lift winches installed on two-stage vibration isolation systems showed that the noise levels from them do not exceed the standard values in the nearest residential premises (through 1-2 walls). For practical purposes, care must be taken to ensure that vibration isolation is not disturbed by random rigid bridges between the metal frame and the supporting surface. The supply cables must have sufficiently long flexible loops. However, the operation of other elements of elevator installations (control panels, transformers, car and counterweight shoes, etc.) may be accompanied by noise above the normative values.
It is forbidden to design the floor of the elevator engine room as a continuation of the floor slab of the ceiling of the living room of the upper floor.
NOISE FROM TRANSFORMERSUBSTATIONSON THE GROUND FLOOR
To protect against noise transformer substations of residential and other premises with standardized noise levels, the following conditions must be observed:
- premises of built-in transformer substations;
- should not be adjacent to noise-protected rooms;
- built-in transformer substations should
- located in basements or on the first floors of buildings;
- transformers must be installed on vibration isolators designed in an appropriate way;
- electrical panels containing electromagnetic communication devices and separately installed oil switches with an electric drive must be mounted on rubber vibration isolators (air disconnectors do not require vibration isolation);
- ventilation devices of the premises of built-in transformer substations must be equipped with noise suppressors.
To further reduce noise from the built-in transformer substation, it is advisable to treat its ceilings and internal walls with sound-absorbing lining.
In built-in transformer substations, protection against electromagnetic radiation must be made (a grid of special material with grounding to reduce the level of radiation of the electrical component and a steel sheet for magnetic).
NOISE FROM ATTACHED BOILERS,BASEMENT PUMPS AND PIPES
Boiler room equipment (pumps and pipelines, ventilation units, air ducts, gas boilers, etc.) must be vibration-isolated using vibration foundations and soft inserts. Ventilation units are equipped with silencers.
In order to isolate the pumps located in the basements, elevator units in individual heating points (ITP), ventilation units, refrigeration chambers, the specified equipment is installed on vibration foundations. Pipelines and air ducts are vibroisolated from the structures of the house, since the predominant noise in the apartments located above may not be the base noise from the equipment in the basement, but the one that is transmitted to the building envelope through the vibration of pipelines and equipment foundations. It is forbidden to arrange built-in boiler rooms in residential buildings.
In piping systems connected to the pump, it is necessary to use flexible inserts - rubber-fabric sleeves or rubber-fabric sleeves reinforced with metal spirals, depending on the hydraulic pressure in the network, 700-900 mm long. If there are pipe sections between the pump and the flexible connector, the sections should be fixed to the walls and ceilings of the room on vibration-isolating supports, hangers or through shock-absorbing pads. Flexible connectors should be located as close as possible to the pumping unit, both on the discharge line and on the suction line.
To reduce noise and vibration levels in residential buildings from the operation of heat and water supply systems, it is necessary to isolate the distribution pipelines of all systems from the building structures of the building at the points of their passage through the supporting structures (input into and out of residential buildings). The gap between the pipeline and the foundation at the inlet and outlet must be at least 30 mm.
Prepared based on the materials of the journal Sanitary and epidemiological interlocutor (No. 1 (149), 2015
