Types of household gas: what gas comes to our apartments + features of household gas

Mechanism of gas poisoning

At the heart of the pathogenesis of household gas poisoning is the ability of methane to displace oxygen both from indoor air and from hemoglobin located in red blood cells.

Of all the components of the air mixture, methane has the smallest mass, therefore, in open space, without having time to get into the lungs, it quickly rises and dissolves in the atmosphere. But due to the limited space in enclosed spaces, it behaves differently. Here, methane can accumulate for a long time without any obstacles, gradually filling the entire space from ceiling to floor.

When its concentration in the inhaled air reaches 25-30% percent, the content in the blood increases significantly. At the same time, hypoxia develops - due to oxygen deficiency, hemoglobin cannot completely remove carbon dioxide from the tissues.

In addition, methane has the ability to penetrate the blood-brain barrier, that is, from the blood straight into the brain tissue. At the same time, it depresses the respiratory center, as well as the trigeminal and vagus nerves. This leads to a decrease in the frequency of respiratory movements. As a result, under the influence of the gas, a multi-vector inhibition of the work of the brain occurs, which, if timely assistance is not provided, can lead to loss of consciousness, to a stoppage of the work of all internal organs and systems. As a result, a lethal outcome is possible.

The system of automatic control and protection against gas pollution and gas leakage in a house, apartment

Dangerous properties of gas fuel:

• the ability of gas to form flammable and explosive mixtures with air;
• suffocating power of the gas.

The components of gas fuel do not have a strong toxicological effect on the human body, but at concentrations that reduce the volume fraction of oxygen in the inhaled air to less than 16%, they cause suffocation.

During the combustion of gas, reactions occur in which harmful substances are formed, as well as products of incomplete combustion.

Carbon monoxide (carbon monoxide, CO) - is formed as a result of incomplete combustion of fuel. A gas boiler or water heater can become a source of carbon monoxide if there is a malfunction in the combustion air supply and flue gas removal path (insufficient draft in the chimney).

Carbon monoxide has a highly directed mechanism of action on the human body up to death. In addition, the gas is colorless, tasteless and odorless, which increases the risk of poisoning. Signs of poisoning: headache and dizziness; there is tinnitus, shortness of breath, palpitations, flickering before the eyes, redness of the face, general weakness, nausea, sometimes vomiting; in severe cases, convulsions, loss of consciousness, coma. Air concentrations greater than 0.1% result in death within one hour. Experiments on young rats have shown that a concentration of CO in the air of 0.02% slows down their growth and reduces activity compared to the control group.

Gas alarm - gas leak sensor, is it necessary to install

Since 2016, building regulations (clause 6.5.7 of SP 60.13330.2016) require the installation of gas alarms for methane and carbon monoxide in the premises of new residential buildings and apartments in which gas boilers, water heaters, stoves and other gas equipment are located.

For buildings that have already been built, this requirement can be seen as a very useful recommendation.

The gas detector for methane serves as a leak sensor domestic natural gas from gas equipment. The carbon monoxide alarm is triggered in case of malfunctions in the chimney system and the ingress of flue gases into the room.

Gas sensors should be triggered when the gas concentration in the room reaches 10% of natural gas LEL and CO content in the air is more than 20 mg/m3.

Gas alarms must control a quick-acting shut-off (cut-off) valve installed at the gas inlet to the room and shutting off the gas supply by a signal from the gas contamination sensor.

The signaling device must be equipped with a built-in system for emitting a light and sound signal when triggered, and / or include an autonomous signaling unit - a detector.

The installation of signaling devices allows you to timely notice a gas leak and disturbances in the operation of the smoke exhaust path of the boiler, to prevent a fire, explosion, and poisoning of people in the house.

NKPRP and VKPRP are the lower (upper) concentration flame spread limit - the minimum (maximum) concentration of a combustible substance (gas, vapors of a combustible liquid) in a homogeneous mixture with an oxidizing agent (air, etc.) at which flame propagation through the mixture is possible at any distance from the ignition source (open external flame, spark discharge).

If the concentration of a combustible substance in the mixture is less than the lower limit of flame propagation, such a mixture cannot burn and explode, since the heat released near the ignition source is not enough to heat the mixture to the ignition temperature.

If the concentration of a combustible substance in the mixture is between the lower and upper limits of flame propagation, the ignited mixture ignites and burns both near the ignition source and when it is removed. This mixture is explosive.

If the concentration of a combustible substance in the mixture exceeds the upper limit of flame propagation, then the amount of oxidizing agent in the mixture is insufficient for complete combustion of the combustible substance.

The range of concentration values ​​between NKPRP and VKPRP in the "combustible gas - oxidizer" system, corresponding to the ability of the mixture to ignite, forms an ignitable region.

Gas detector for LPG

The building regulations do not contain mandatory requirements for the installation of gas alarms in rooms when using liquefied gas. But liquefied gas alarms are commercially available and installing them will undoubtedly reduce the risks for you and your loved ones.

Main gas pipelines. High, medium and low pressure gas pipelines Glossary

The gas pipeline is an important element of the gas supply system, since 70.80% of all capital investments are spent on its construction. At the same time, 80% of the total length of distribution gas networks falls on gas pipelines of low pressure and 20% - for gas pipelines of medium and high pressures.

Gas pipeline classification by pressure

In gas supply systems, depending on the pressure of the transported gas, there are:

• high-pressure gas pipelines of category I (operating gas pressure over 1.2 MPa);
• high-pressure gas pipelines of category I (operating gas pressure from 0.6 to 1.2 MPa);
• high-pressure gas pipelines of category II (operating gas pressure from 0.3 to 0.6 MPa);
• medium pressure gas pipelines (operating gas pressure from 0.005 to 0.3 MPa);
• low pressure gas pipelines (operating gas pressure up to 0.005 MPa).

Medium pressure gas pipelines through gas control points (GRP) supply gas to low pressure gas pipelines, as well as industrial and municipal enterprises. Through high-pressure gas pipelines, gas flows through hydraulic fracturing to industrial enterprises and medium-pressure gas pipelines. Communication between consumers and gas pipelines of various pressures is carried out through hydraulic fracturing, GRSH and GRU.

Location of gas pipelines (classification)

Depending on the location, gas pipelines are divided into external (street, intra-quarter, yard, inter-workshop) and internal (located inside buildings and premises), as well as underground (underwater) and above-ground (above-water). Depending on the purpose in the gas supply system, gas pipelines are divided into distribution, gas pipelines-inlets, inlet, purge, waste and inter-settlement.

Distribution pipelines are external gas pipelines that provide gas supply from main gas pipelines to gas input pipelines, as well as high and medium pressure gas pipelines designed to supply gas to one object.

The gas pipeline-inlet is considered the section from the place of connection to the distribution gas pipeline to the shut-off device on in water.

The inlet gas pipeline is considered the section from the disconnecting device at the entrance to the building to the internal gas pipeline.

Inter-settlement pipelines are distribution gas pipelines located outside the territory of settlements.

The internal gas pipeline is considered the section from the gas pipeline-input (introductory gas pipeline) to the connection point of the gas appliance or heating unit.

Materials for gas pipelines

Depending on the material of the pipes, gas pipelines are divided into metal (steel, copper) and non-metallic (polyethylene).

There are also pipelines with natural, liquefied hydrocarbon gas (LHG), as well as liquefied natural gas (LNG) at cryogenic temperatures.

The principle of construction of distribution systems of gas pipelines

According to the principle of construction, distribution systems of gas pipelines are divided into ring, dead-end and mixed. In dead-end gas networks, gas flows to the consumer in one direction, i.e. consumers have a one-way supply.

Unlike dead-end networks, ring networks consist of closed loops, as a result of which gas can be supplied to consumers through two or more lines.

The reliability of ring networks is higher than dead-end networks. When carrying out repair work on the ring networks, only a part of the consumers connected to this section is turned off.

Of course, if you need to order gas supply to the site or perform gasification of an apartment building, instead of memorizing the terms, it is more profitable and more efficient to turn to reliable certified contractors. We will carry out work on conducting gas to your facility with high quality and within the agreed time frame.

LLC "GazComfort"

Office in Minsk: Minsk, Pobediteley Ave. 23, bldg. 1, office 316АOffice in Dzerzhinsky: Dzerzhinsk, st. Furmanova 2, office 9

Recommendations for the safe use of gas

In practice, most explosions and fires are caused by the human factor, neglect of safety precautions when using gas, negligence in handling gas equipment.

To protect yourself and loved ones, you need to follow a number of norms and generally established rules. This will help prevent explosive situations and all the adverse consequences associated with a gas leak.

Rules for the operation of gas equipment

Any gas equipment should be purchased only from specialized companies that can provide certificates for the sale of this type of product

It is necessary to pay attention to the fact that instructions for the safe operation of the device must be present in the kit. . Installation and repair work must be carried out by specialists of the relevant organizations

Unauthorized gasification of a house or apartment, replacement, reinstallation and changes in the design of gas appliances are strictly prohibited.

Installation and repair work must be carried out by specialists of the relevant organizations. Unauthorized gasification of a house or apartment, replacement, reinstallation and changes in the design of gas appliances are strictly prohibited.

It is important to adhere to the following rules for the operation of gas equipment:

• carefully read the instructions and follow the recommendations indicated in it;
• do not use the equipment for other purposes (heat the apartment with a gas stove);
• monitor the performance of appliances and ventilation, annually invite specialists to check the draft;
• ensure normal air flow in the room, do not isolate ventilation openings, do not block gas pipes;
• do not leave functioning devices unattended, especially in rooms with young children, and also if the devices are not designed for continuous operation and are not equipped with appropriate automation;
• do not tie clotheslines to gas pipelines;
• close gas valves and taps on the pipeline before leaving the house, in case of a long absence, it is better to turn off the electricity;
• do not blow out or fill with water or other liquids the flame on the burner.

It is very important to regularly check the condition and tightness of hoses, fittings, threaded connections. The optimal length of the flexible hose is no more than 2 meters, the maximum service life is up to 4 years

The hose must be tightly put on the gas cock, but it is not recommended to overtighten the clamping collar.

Most often, gas leaks occur due to ruptures in the hoses connecting the stove to the gas pipeline, seal failures in the area of ​​threaded joints. Another common reason is the inattention of users who forget to close the valves responsible for the gas supply.

Feeling the characteristic smell of gas in the apartment, you must immediately turn off the burner taps and valves on the pipeline. You should also open doors, windows and thoroughly ventilate the gassed room, making sure that everyone present quickly leaves it.

People affected by the gas must be urgently removed to fresh air and given first aid:

• lay on your back so that the legs are higher than the body;
• remove tight clothing;
• cover, rub the chest, bring ammonia;
• turn on its side when vomiting;
• drink as much water as possible.

You can not do anything that can create a spark or flame: smoke, light a fire, turn on / off electrical appliances, lighting, press the call button, use mobile devices.

It is advisable to immediately report the incident to the emergency gas service. While the rescuers arrive, it is worth warning the neighbors about the situation.

Leak Detection Methods

To detect a gas leak in a room, several proven methods are used. The easiest and most common option is to inspect the surface by applying soapy water along the gas pipes. In the event of a leak, bubbles form in problem areas.

The surest way to avoid trouble is to install a carbon monoxide detector.

This modern ultra-sensitive device - a gas leak detector - will instantly notify you of the slightest problem by means of a sound or light alarm

In addition, you can determine the leak by ear or smell. With a strong leak, the fuel mixture escapes from the pipes with a whistle. It is easy to feel the specific smell of odorants added to the structure of the fuel during processing.

Precautionary measures

In order to prevent the occurrence of a dangerous situation and not be exposed to the risk of intoxication with household gas, it is necessary to take care of your own safety in advance.

To do this, you should perform the following activities:

• compliance with safety rules when working with gas equipment and distribution systems;
• timely replacement of hoses and broken parts;
• regular inspection of pipes and equipment to identify and eliminate breakdowns;
• a ban on the use of stoves for space heating;
• control of the state of shut-off valves;
• closing valves on gas cylinders after their use is completed;
• before leaving for a long time, it is recommended to limit the gas supply and close all valves;
• keeping burners dry;
• draft protection when cooking to prevent the flame from blowing out;
• use of blocking systems for valves on the stove if there are children in the house.

Severity of poisoning

In case of poisoning with household gas, oxygen starvation develops in the body - hypoxia. The replacement of oxygen by substances that make up the gas has a depressing effect on the work of the most important systems, in particular, the respiratory and nervous systems.

With an increase in the concentration of domestic gas in the air, poisoning can develop in several forms. There are three main degrees of severity of intoxication:

• Light. Changes in the body are insignificant, there is a slight dizziness, weakness, there is a feeling of lack of air.
• Medium. The pulse quickens, there are disorders of cognitive functions, hallucinations, uncoordinated movements.
• Heavy. Changes in the body become critical, pulmonary edema, cerebral edema, and myocarditis develop.

With an increase in the level of gas content in the room to critical levels, an instant form of intoxication may develop. In this case, it is enough to take just a few breaths for the toxins to provoke a loss of consciousness. Death occurs after about 5 minutes.

What gas is supplied to residential buildings and boiler rooms

Gas supply: about natural gas, methane and propane

In different countries, different gas fuels are supplied to homes: natural gas (including from gas condensate), methane (methane, CH4), propane (propane, C3H8). Both methane and propane are commonly found in natural gas, a mixture of hydrocarbons.

But! Gas can be falsified - diluted like milk, extract valuable substances: read How much gas costs through a gas meter, or how much heat from gas costs - with a gas meter installedCan the gas supplier add something to the gas so that the gas meter shows more(the main thing is that gas consumers are satisfied. out of ignorance)

There are restrictions on the height of buildings for gasification of multi-storey buildings, this is due to fire and explosion hazards - usually houses above 12-14 floors are not gasified to apartments. Probably, the number of storeys of gasification depends on the seismic hazard of the area, the design of buildings.

I know a 14-storey gasified tower house in the city of Varna (Bulgaria), with a stairwell in the middle. And the construction seismic hazard is 7 points (which means the points and magnitudes of earthquakes).

Gas supply

Gas is supplied through gas distribution pipes-networks (piped-in public utility services) or from local gas storage facilities, where it is delivered in a compressed or liquefied form - by cars, railway tanks - "gas carriers" or individually - in cylinders. Technologies for the supply of compressed or liquefied natural gas, propane, methane - compressed natural gas - CNG, or liquid natural gas LNG, LPG, LPG-propane. Gas supply is not “just a pipe from a well”.

Urban multi-apartment residential buildings or boiler houses are usually supplied with natural gas from the network, after cleaning and conditioning.

The composition of the supplied gas depends on the modification of the terminal gas household equipment, and no one, except for the gas distribution company, can say for sure what kind of gas they supply to the houses.

For example, the European company "Gorenie" ("Gorenje", from the former Yugoslavia, from Slovenia), I remember that in the specification for gas stoves, they indicated the type of burners for various gases. For deliveries are to the USA (there were before, now I don’t know), to Western Europe, Eastern Europe, “CIS countries”.

What is natural gas made of - gas composition

Natural gas consists of hydrocarbon gases - methane by 80-100% and methane homologous hydrocarbons: ethane (C2H6), propane, butane (C4H10), and non-hydrocarbon substances: water (in the form of steam), hydrogen, hydrogen sulfide (H2S) , carbon dioxide (CO2), nitrogen (N2), helium (He).

The more hydrogen in the molecular composition of the "gas", the cleaner the gas burns. That is, the "ideal" gas in the pipe is methane CH4.

Hydrogen sulfide and water are the most unpleasant components of network gas. Hydrogen sulfide successfully reacts with metals, especially in the presence of water - that is, it causes corrosion of gas pipes, "gas boilers" (heating equipment and boilers), metal chimneys. Hydrogen sulfide concentrations are usually not high, 0 and 0 tenths, however, gas pipelines with terminal gas equipment must operate for more than a dozen years.

I've never heard of frozen water forming ice plugs in gas pipes.

Nitrogen in gas does not affect gas pipelines and gas equipment in any way, just “waste rock” that reduces the calorific value of gas. Nitrogen even makes pressure testing of gas pipelines and networks (pressure test) and purging to clean networks from natural gas.

On the danger of explosion and fire "from gas"

Explosiveness.The concentration of gas for an air explosion (namely, an explosion, with supersonic speed, and not cotton - fast burning) is a very "thin" value, depending on the gas composition, temperature, pressure, air composition, etc. Natural gas concentrations from 5 to 15 are considered explosive. volume percent, and natural combustion with air under normal conditions without combustion catalysts occurs at about 650 degrees Celsius.

Combustible gases in natural gas are lighter than air, so “theoretically” places of dangerous concentration of gas should occur in the upper floors of the house, but the practice is much more complicated.

The geography of world natural gas production and, accordingly, the diversity of the composition of natural fuel gases is illustrated by a map of natural gas production from Wikipedia. The article uses some information from Wikipedia

article last modified 09Mar2011, 26Oct2017

4 What will tell the color of the flame burners

The flame in the burners can have a variety of shades, which indicate the features of the combustion of fuel. The intense blue color of the fire indicates the homogeneous structure of the gas that is fed into the stove. Homogeneous and high-quality fuel burns completely, emits the maximum amount of heat and the minimum amount of harmful substances into the environment.

It is not uncommon for apartment owners to notice a bright red or yellow flame in their burners. Any shades other than blue indicate that the burner is receiving low quality fuel with air impurities. Not only can low-quality fuels be quite dangerous to use, but they also produce significantly worse heating.Poor gas quality will lead to the fact that for the operation of the heat supply system it will be necessary to spend a larger amount of an expensive resource and pay more on utility bills.

Because of this, we recommend paying attention to the color of the fire on the stove and in the boiler. Most often, management companies are responsible for supplying low-quality fuel to apartments.

Representatives of the UK sometimes deliberately reduce the content of carbon dioxide and hydrocarbons in the fuel in order to increase their income. In any case, the discovery of a change in the color of the flame is an excellent reason to contact the responsible authorities for clarification.

Poor operation of the gas supply system can not only increase the costs of users of an apartment or house, but also lead to premature wear of installed equipment, its failure and even emergency situations. We are directly interested in the fact that high quality natural gas is supplied to our homes, therefore, if any suspicions arise about the content of impurities in the fuel, it is necessary to check the existing equipment by calling gas workers to the house.

What gas is used in residential buildings, and under what pressure

Before being supplied to the house, the gas is cleaned and supplemented with some components, which increases the level of safety of its use. Further, methane, through many kilometers of pipelines, reaches the gas distribution station. The pressure level in the pipelines is very high and reaches 11.8 MPa.

The composition of the gas in the apartments

The gas supplied to the apartments has the following components:

• propane
• methane;
• water vapor;
• carbon dioxide;
• hydrogen sulfide;
• ethyl mercaptan and ethanethiol - for a pungent odor.

How does natural gas differ from liquefied gas, and propane from methane

Sufficiently used today is natural gas (methane). It can be extracted by the traditional method (field development) and by processing organic waste (the so-called biogas). Through the pipeline, methane is delivered directly to the citizens in the house.

Liquefied gas (propane-butane mixture) is currently the most widely used. Its storage is carried out in cylinders and tanks, at a pressure of 16 atmospheres. Residents of houses without a central gas supply system purchase methane cylinders weighing up to 40 kg, with a capacity of up to 50-80 liters.

In houses connected to the gas supply system, liquefied fuel comes from underground tanks.

Depending on the time of year, different gas is supplied to consumers. It differs in its composition. This is due to the evaporation temperature of its various components.

What will the color of the burner flame say?

If gas combustion is accompanied by the appearance of bright yellow or red tongues, then this will indicate an excess of air and other harmful components. Fuel with excess impurities is characterized by reduced heat productivity, which increases its consumption and the amount payable for consumed resources. The use of gas with impurities is dangerous for the home. May shorten the life of the equipment.

Gas pressure in the gas pipeline of a residential building

For the needs of the population at gas distribution stations, the pressure of methane is reduced to 1.2 MPa. This indicator is enough for heating the house and cooking. Also, the fuel is subjected to additional cleaning. After that, it goes to the citizens through the gas pipeline.