Smell from the sewer in the apartment: types of technical faults and ways to eliminate them

The specific smell from the sewer in the apartment is hardly compatible with a cozy home atmosphere and thoughtful home design. You should not try to mask it with various air flavors: you need to establish the cause and solve the problem.

We will tell you how to deal with the negative atmosphere created as a result of the spread of unpleasant volatile compounds. The article proposed for consideration describes in detail the causes of sewer odor and methods for eliminating it. Taking into account our recommendations, the disgusting “aroma” will disappear forever.

Sources of stench: common options

Modern houses are equipped with a sophisticated sewer system designed to remove residual waste products. Its operation is accompanied by specific odors, since wastewater flowing through the pipes emit hydrogen sulfide and other unpleasant-smelling substances.

When the sewerage system is working properly, the “aroma” in the premises (including the bathroom, kitchen, toilet) is almost imperceptible. Its appearance indicates a malfunction in the functioning of technical communications or plumbing fixtures.

When a sewer smell appears, it is important to determine its source. If this cannot be done on your own, it is important to immediately contact a specialist.

The most common causes of stench can be:

• Mistakes made when installing the sewer system. The appearance of odors in the room may be due to improper installation of pipes or loose connections.
• Burst of a sewer pipe in the central or apartment distribution system. A leak can be either obvious or almost invisible: a microcrack or a joint not treated with sealant is often enough for gases and moisture to leak through.
• Inadequate assembly quality of the siphon or its malfunction. This component of plumbing design plays an important role in preventing the entry of foul gases.
• Blocked pipes or drains. Household waste, hair, and food waste that accumulate in siphons or pipes begin to rot, releasing a specific “aroma.”
• Malfunction of the water seal , as a result of which the “water plug” is destroyed, which prevents the appearance of sewer odors.
• Defects in the functioning of ventilation , which is equipped in apartment and private buildings. The system is designed to remove stench from the sewer system; If she doesn't do a good job, the stench penetrates the apartments.
• Incorrect connection or violation of operating instructions for the washing machine. In some cases, a useful unit becomes a source of a specific odor.

In addition to those listed, there are many other reasons that cause “odors” in the room. Some of them are easily removable, others require the help of specialists, and often extensive, expensive work.

Below we will look in detail at the various sources of stench and tell you what measures need to be taken in specific cases.

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Odor is the cause of sewerage problems

Lack of ventilation and blockages in pipes

Siphon clogged and water seal leaking

Major damage to pipes and equipment

The seal of the sewer system is broken

Any hole in the sewer becomes a source of leaks and the penetration of miasma.

The tightness may be broken for the following reasons:

• the joints between pipes, couplings, tees, and devices are not sealed;
• some section of communications cracked, burst, broke.

The elements of the sewer system are connected to each other with sockets and fittings, inside of which there are rings made of rubber and silicone. The inner diameter of these seals is 4 cm, the outer diameter is 5.

If the rings are missing somewhere or their cross-section is smaller than required, the joints begin to leak. Puddles appear on the floor. Evaporating from them, the wastewater emits a specific odor.

How to fix the situation

Obvious leaks are easy to detect; their presence is indicated by puddles on the floor. However, to be on the safe side, the apartment owner needs to check all communications and connections. After all, leaks can be hidden.

When checking, you can use a light rag or napkin, which wipes all pipes and connections. If drainage leaks somewhere, a wet spot will remain on the paper or fabric.

How to get rid of miasma in this case:

1. the cracked, leaky section of communications is removed and a new, intact pipe is installed in its place;
2. if a joint leaks, a seal is inserted into it or a defective, torn, or crumpled ring is replaced.

The diameter of the ring must correspond to the cross-section of the pipes being joined. You can buy a set of seals at any large plumbing store.

Improper installation of communications

If residents who have moved into a new house feel a not-so-pleasant “aroma” in the rooms, perhaps the builders or DIYers made mistakes when installing the sewer system.

Due to violations associated with the laying of pipes - especially non-compliance with the angle of inclination, which is prescribed in the standards, wastewater in the pipes can stagnate, causing a specific odor.

When laying a sewer system, it is important to comply with engineering requirements: all work must be carried out in strict accordance with current regulations

A radical way to get rid of the stench will be a complete replacement of communications with the installation of a new system in strict accordance with technical specifications.

In some cases (when using metal-plastic pipes), the situation can be saved by adjusting tightened pipe connections, replacing gaskets, and installing specially selected sealing collars.

In order to prevent clogging, it is periodically necessary to flush the sewer system, the rules for which will be introduced in our article.

Problems of public sewerage

If unpleasant odors are especially noticeable in rooms on the lower floors and in the entrance, the reason for their appearance most likely lies in the basement wiring.

The most obvious reasons are:

• damaged pipe with leaking sewage;
• blockage of the centralized system caused by the actions of residents who violate the accepted regulations for the operation of plumbing fixtures.

Problems that arise in the centralized communications system are considered an emergency. Liquid leakage not only poisons the air, but also promotes the development of microbes, causes dampness in residential areas, and undermines the foundation of the house, causing its destruction.

To resolve the situation, you should immediately contact the Management Company (ZhEK), writing a detailed statement about the situation. After renovation, it is important to ventilate the basement well to remove accumulated moisture.

You can get rid of the negative smell in apartments on the upper floors by simply increasing the operation of the vent riser:

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Step 1: Purchase a check valve for the waste riser

Step 2: Arranging a ventilation duct for installing a pipe

Step 3: Assembling and installing the valve mounting pipe

Step 4: Installing a check valve in the pipe

Siphon clogged

If the siphon is usually clogged, an unpleasant sewer smell may also appear in the apartment. Drains very often accumulate in the siphon elbow, which over time begin to decompose and emit a rather unpleasant aroma. If the water seal is clogged, it must be washed using chemicals that can be purchased at any specialized store. If necessary, the question of how to remove the smell from the toilet can be solved by mechanically cleaning the water seal.

In most cases, corrugated siphons are susceptible to clogging, which is explained by the folded surface of the inside of the pipe. It is in the folds that debris, fat and waste products are retained. To wash the corrugated siphon, complete dismantling of the device is required.

Malfunctioning of apartment wiring

If the smell is felt only in places where hygiene devices are installed, it can be assumed that it is caused by defects in the apartment wiring.

If an unpleasant odor appears in the room, you should first inspect the wiring in the apartment, checking the tightness of the connections and the presence of hidden leaks

As a rule, a leak from a pipe is immediately visible, but other, less visually noticeable options are also possible, which include the options described below.

Result of hidden leaks

In sewer systems made of traditional cast iron or currently popular plastic, fistulas, cracks, and other defects may appear.

Since pipes are often walled up in walls or floors, it is quite difficult to identify and eliminate such defects. It is especially difficult to determine leaks in interfloor partitions with difficult access to the sewer system.

Leaks in the sewer system often become the source of an unpleasant odor. To eliminate it, you need to replace the damaged element or seal it with a special compound

Where an unpleasant odor appears, you should, as far as conditions allow, immediately check the pipes and the places where they come into contact with the plumbing. If necessary, you should call a specialist who will diagnose and professionally solve the problem.

Usually, to eliminate a leak, the system is replaced or sealed with modern materials or a cement mixture that does not contain sand (for cast iron pipes).

To prevent such defects, when installing apartment wiring, you must remember the following rules:

• when installing communications, use only high-quality pipes and fittings;
• carry out installation according to a scheme that provides for a minimum number of joints, since leaks most often occur in such units;
• when installing pipes, provide access to installed systems;
• take care of high-quality waterproofing of walls, floors in bathrooms, and in the kitchen.

Such measures will provide effective protection against leaks, and, if necessary, will allow the leak to be quickly eliminated.

Lack of tightness of the system

The appearance of a sewer smell in a bathroom or kitchen can also be caused by a leak in the pipes or when they are connected to a sink, sink, or other plumbing fixtures.

Particular care should be taken when connecting sewer pipes. To prevent the release of moisture and odors, joints should always be treated with sealant

It is important to carefully check the nodes connecting the devices to the sewer network, secure them, and then carefully treat them with sealant to eliminate minimal gaps and cracks. Often such a simple manipulation allows you to get rid of the smell of sewerage both in the bathrooms and throughout the apartment.

Leaks in sewer pipes

It may stink due to leaks. It is not easy to detect them: pipes are usually hidden in boxes and covered with tiles. Therefore, plumbers advise to always provide access to utility systems using hatches, and also not to get carried away with fittings: corners, tees - leaks most often occur at the joints .

If a problem is found, it must be resolved. When there are plastic pipes in a country house, it is enough to replace the rubber seal . For reliability, it can be treated with silicone sealant.

If cast iron pipes were used during construction, you will have to tinker a little longer. Ideally, the problem area needs to be replaced, which will have to be done sooner or later. But as a temporary measure, you can do the following.

Prepare a piece of rubber and two clamps with a diameter equal to the diameter of the pipe. A rubber patch can be cut, for example, from a car tire. Its length should be equal to the circumference of the pipe, that is, encircle it entirely. You need to wrap the pipe in rubber, press it tightly to the metal and secure it with two clamps. This patch will help keep the crack dry until the plumber visits.

Blockages and methods for eliminating them

A common source of foreign odors is blockages that can occur in siphons and pipes. To avoid such a problem, you must follow the rules for using plumbing fixtures.

The mesh in the drain hole of the sink or sink traps dirt, effectively preventing the formation of blockages in the siphon or sewer pipes

Such basic devices as protective nets for catching debris installed on the drain holes of the sink or sink can be of great help.

To eliminate “odors” caused by clogged pipes, it is important to clean them regularly, which can be done in different ways:

• traditional plunger;
• cable;
• more complex hydrodynamic devices;
• special chemicals.

When choosing a method, it is important to take into account both the degree of blockage and the material from which the sewer pipes are made. Thus, for systems made of cast iron, it is undesirable to use cleaning products containing aggressive components.

Repairing small cracks

Pipes can leak at the joints. If the pipes have moved, they must be returned to their place. When rubber seals on plastic pipes break, they will need to be completely replaced with new ones.

In order to remove leaks in sewer channels, water is drained and dried. Next you will need to saw off a small piece of pipe of the same length and cut it lengthwise. Where a crack or tear has formed, it is necessary to anoint it with special glue. Next you should put the patch and press on it. If microcracks have formed in cast iron fixtures, then you will need to use cold welding.

Problems with the water level in the water seal

Possible problems in the operation of the siphon are often associated with a water seal - a water plug, when it is “knocked out”, odors and gases begin to enter the apartment.

A similar situation can arise when the pressure in the sewer system increases, the air coming from the pipes is able to “knock out” the water seal. This usually happens when a large volume of liquid is suddenly drained from the tank. However, the process can also be gradual, allowing gases to enter the apartment unnoticed over time.

A water seal or “water plug” located in the siphon elbow creates a reliable barrier that prevents sewer gases from entering the apartment

When the pipe cross-section is completely blocked by drains, the sewer system is filled with rarefied air, which draws liquid from the siphon like a pump. Once the water is drained, the water seal will be completely eliminated, and gases will begin to flow freely into the premises without encountering any obstacles.

The latter option is usually caused by two reasons:

1. Using small diameter pipes that do not correspond to the dimensions specified in the relevant regulatory documents.
2. Formation of blockages or icing, partially or completely blocking the cross-section of communications.

To eliminate the first reason, it is necessary to replace the pipes with components of proper quality. To eliminate blockages, the system should be cleaned; When ice forms, warm it well with hot water.

Installing a vacuum valve will help get rid of the malfunction of the water seal:

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Types of vacuum valves for sewerage

Connecting a siphon to the sewer through a valve

Device for supplying air to the circuit

Device for eliminating negative odors

Other types of problems

There are other types of plumbing problems when the sewer smells. It is necessary to have an idea why the toilet smells like sewage in order to carry out repair work independently and in a timely manner.

Clogged sewer pipes

1. If there is hard water, the pipes become clogged with limestone deposits. They are eliminated using special chemicals that dissolve these formations.
2. The cause of the clog can be the accumulation of toilet paper and hair residues, which retain large particles from the wastewater. At this moment, a characteristic smell appears from the sewer. For cleaning, use a plunger, chemical agent or cable.
3. It is difficult to remove particles of building materials and rags from the system, which cause severe clogging. In such a situation, use a plumbing cable or special equipment.
4. Sewer passages are often contaminated with fatty deposits, which are prevented by the periodic pouring of boiling water into the pipes in large quantities.

Incorrect pipe installation

Such mistakes can be made if the installation was carried out by an inexperienced person. This work must be performed by a master who is aware of all the intricacies of installation. After some time, improperly installed sewer pipes cause an unpleasant odor, the reason for which lies in the violation of the pipeline slope. To remove the problem, you will need to redo the system. This work is characterized by the complexity of calculating the slope angle.

Sewer system installation errors

Poor functioning of plumbing fixtures can be caused by problems with the siphon and narrowing of the lumen due to the accumulation of dirt. These problems can be eliminated by cleaning. The water plug may dry out or break off if the rules for installing sewer parts are violated. Sometimes elements with a diameter smaller than those required by building codes are used for the system. The sewage system will work stably if the section of the part is not blocked by drains.

Otherwise, the installed siphon will discharge and fail. If the system is located in a cold room, it will freeze in winter. In such a situation, the ice is melted with hot water and hoses with a larger diameter are selected.

Toilet connection diagram.

When a drain pipe becomes clogged, the plumbing system malfunctions. This part is located on the roof and helps equalize the pressure in the system. When this area becomes clogged, the sewer system stops performing its functions.

Each release of water leads to a breakdown of the siphon, which causes gases to enter the room. To eliminate the stench, the sewer passages are cleaned so that the question does not arise as to why the bathroom smells like sewer.

Poor ventilation

If, after a full inspection of the bathroom, the source of the stench was not found, you need to check the ventilation ducts, which apartment owners often forget about. The room must be thoroughly ventilated, so ventilation is checked regularly. Inspection is carried out once every 30 days. In a private house, a working ventilation system will remove all odors that are unpleasant to humans.

Violation of system tightness

Another source of stench can be cracks in pipes. In this case, liquid appears under the sink or toilet. The leak area is sometimes difficult to determine due to the presence of furniture in the room or small area

To search, you will need to take a flashlight and inspect all the parts, paying attention to connections and joints

A leak is indicated by drops on the outside walls of the pipes. To restore the system, it is necessary to replace the area or seal the hole. Such problems can be prevented through preventive measures. To achieve this, high-quality and reliable material is used during installation, waterproofing of the floor and walls in the bathroom is carried out in a timely manner, and the location of system elements in hard-to-reach places is avoided.

Incorrect operation of ventilation systems

The cause of the unpleasant odor may lie in the improper functioning of the ventilation system installed in the house. The natural pull of such communications is sometimes not enough to successfully cope with the task assigned to them - eliminating the stench from the sewerage system.

You can check this indicator quite simply: attach a regular piece of paper to the ventilation grille, which is usually located in the bathroom and/or kitchen. If there is good traction, the sheet will stick to the holes; if there is insufficient traction, it will fall to the floor.

You can deal with this problem in the following ways:

1. Do it yourself: additionally installing a fan that will increase the level of air circulation.
2. With the help of specialists: professionals will clear blockages in installed ventilation ducts, increasing their draft.

After solving the problem, it is also necessary to carry out waterproofing measures in sanitary premises.

Bathroom Features

The bath is connected to the general sewer system by a flexible pipe. It must be curved and have a drop sufficient to prevent dirty water from returning. This tube should also have a water seal (as in the photo), which will prevent you from having a problem when the bathroom smells like sewage. If the obstacle in the form of a water plug disappears, the unpleasant odor has unhindered access to the bathroom.

In the case of a combined bathroom, the number of reasons leading to the appearance of an unpleasant odor increases significantly (it is necessary to check the toilet and the communications leading to it, the common riser). If the bathroom has neither a riser nor a toilet, then finding the source of the problem is much easier. Most often, the reason why the bathroom smells like sewer is due to violations in the connections of sewer pipes with bathrooms or errors made during installation (read: “Why does the toilet smell like sewer, getting rid of the smell”). An unpleasant odor often occurs in rooms where the operating rules of the system are violated or there are problems with the water seal.

A washing machine is often installed in the bathroom

It is important to insert the drain hose correctly. In addition, there is a ventilation hole in the bathroom, thanks to which fresh air flows in.

The cause of the trouble may also be hidden in the ventilation duct.

Incorrect operation of the washing machine

The reason for the specific “aroma” may be a familiar unit - an automatic washing machine.

With insufficient care, colonies of fungi and microorganisms can settle in the washing machine drum, causing unpleasant odors in the room

The odor may be caused by the following reasons:

• Incorrect connection of the device to the hydraulic valve, causing waste to enter the system. To fix it, it is better to disconnect the hose from the sewer, leading it to the toilet or sink.
• A clogged drain pump filter (most often it is located at the bottom of the machine). Sometimes, to eliminate an unpleasant odor, it is enough to clean this part.
• Plaque on the walls of the tank or tray for detergents, which is caused by the development of mold and other microorganisms on the surface. To eliminate them, it is important to regularly clean the components of the washing machine with disinfectants, vinegar, and citric acid.

To prevent a useful unit from poisoning the atmosphere with a stench, it is important to follow the rules for caring for this type of household appliance. It is advisable to periodically turn on a high-temperature washing mode, which allows you to get rid of harmful fungi and bacteria.

The best way to permanently get rid of the possibility of an unpleasant odor from the washing machine is to connect it to a bottle siphon under the sink in the kitchen or under the sink in the bathroom:

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Step 1: Preparing the washing machine hose for connection

Step 2: Location of Hose Outlet for Connection

Step 3: Connecting the drain hose to the siphon

Sealing ring for drainage

Dry cleaning

Mechanical cleaning itself does not have a long-term effect. Despite the elimination of a large amount of intensively rotting waste, there still remains a constant factor in the arrival of wastewater. After mechanical treatment, sanitary treatment will be very effective.

The following chemicals are widely used:

1. Nitrate cleaners. Consist of nitrates and other impurities. They are known for their aggressive action, which makes them highly effective. A significant reduction in unpleasant odor is felt immediately after starting to use nitrates. Among the negative aspects, it is necessary to note their danger to the environment. If there is a pit with an open bottom on the site, then nitrate and formaldehyde products are not the best option. They are the most affordable, because, in fact, they are ordinary nitrogen fertilizers used by gardeners and farmers;

   
   Nitrate stink remover

2. Acids. They act in the same way as nitrates. First, sludge and solid waste are dissolved, and then all bacteria are neutralized. They should not be used in plastic containers or open pits;

   
   Acidic solutions for odor removal

3. Ammonium is used only in summer cottages or cesspools that are not connected to a residential building. This is explained by the high sensitivity of these compounds to detergents and chlorine in water. Of the options listed, this remedy is the safest.

There are two ways to carry out sanitary cleaning with chemical compounds: first remove most of the feces mechanically or immediately fill the pit with chemicals. Naturally, the first option is more effective, but the second is much easier to implement.

Video on the topic:

How to eliminate odor from a cesspool using chemicals:

1. Depending on the chosen product, it will need to be dissolved in water or poured (filled) in its pure form. Consider the required concentration. Too high a chemical content can damage the structure of the septic tank. This is especially important for plastic and metal tanks;
2. The presence of air in the container is not necessary, but in order to avoid rising gases and overflowing the drain, it is better to open the inspection hatch in the first few hours;
3. The liquid is removed from the drain after chemical cleaning is completed. There is no need to rinse the cesspool with clean water.

Other causes of unpleasant odor

In addition to the reasons listed above, quite often one has to deal with other sources of stench that are indirectly related to the sewerage system.

Mold and mildew indoors

Specific “flavors” may be associated with the vital activity of single-celled organisms. If there is insufficient waterproofing or freezing of surfaces, colonies of mold fungi that emit putrid odors may develop on the walls and ceilings of the bathroom or other rooms.

To get rid of microorganisms, you need, first of all, to improve the premises by eliminating leaks and insulating partitions. Areas affected by fungus must be thoroughly cleaned with a spatula, rinsed with a washing-off composition with the addition of vitriol, dried well, and then covered with a chalk composition.

Poor quality plumbing fixtures

Various plumbing fixtures can be sources of stench. The “aroma” can be produced by a residue that accumulates due to stagnant water in the toilet tank and on its piston. To get rid of it, you need to regularly clean the plumbing with disinfectants.

An unpleasant odor may be associated with newly purchased plumbing fixtures made of low-quality plastic. To avoid problems, it is better to purchase kits from trusted manufacturers, made from certified raw materials.

The source of the stench in the apartment can be a leaking faucet. Constantly flowing water from it can cause rotting of a wall or other surface.

The cause of the stench may be a leaking faucet that has caused rotting of the adjacent surface. It is important to change gaskets and valves on time, keeping the taps in perfect condition.

Preventative measures to prevent sewer stench

Simple preventive measures will help prevent smell from the kitchen chimney:

• Do not allow any leftover food to go down the drain.
• Install a household waste disposer.
• Equip your bathroom and kitchen fixtures with special grates that trap dirt.
• Do not use Mole frequently or unnecessarily. This is a very strong tool that eats away not only blockages, but also connections, hoses and pipes.
• Check the operation of the ventilation system in a timely manner. If you have frequent problems with stench in your home, install a forced ventilation device.
• Perform preventative cleaning once a week using a mild detergent or baking soda.
• Monitor the condition of the sewer system. Repair small cracks immediately.
• Deep clean your bathroom monthly to prevent mold, rot, loss of damp cloths, and standing water.

By following these simple recommendations, you will keep your plumbing in perfect condition and prevent odors in the bathroom, kitchen and toilet.

Sewer smell in a private home

Private houses are usually equipped with a local sewer system, which is characterized by extreme sensitivity. The slightest change in operating conditions can cause the appearance and rapid spread of stench.

In addition to the above reasons (blockages in pipes, leaks, malfunction of the siphon and water seal), residents of cottages and country houses often encounter a specific source of stench. Namely, the operation of a wastewater treatment facility (septic tank), where wastewater settles and is subsequently purified by microorganisms.

When the bacteria die, waste processing stops, and residents are faced with the problem of how to urgently eliminate the monstrous smell from the sewer that has taken over the entire house.

The death of microorganisms that are important in wastewater treatment can cause an unpleasant odor in a private home

The extinction of microorganisms can be triggered by the following factors:

• Using aggressive household chemicals containing chlorine or other similar components.
• Shallow laying of pipes and septic tank zones into the soil. To prevent icing of water in the sewer system, they must be below the freezing level of the soil.
• Prolonged lack of drainage, which may be caused by the long absence of the owners. In this case, the bacteria are left without a nutrient medium, as a result of which their colonies die.

To eliminate these reasons, you should be well aware of the rules for using a septic tank and strictly follow them.

Common Causes

The sewer system may smell unpleasant due to errors made in the design and installation of the pipeline. Among them are the following:

• there is no fan ventilation, which is necessary for blowing out the drain;
• the system outlet is located below 4 m from the window level;
• there is no head on the fan pipe;
• the ventilation duct for air removal is located close to the house;
• insufficient height of the fan outlet.

If the siphon breaks, an unpleasant odor may also appear. This device retains water, which acts as a plug between the room and the sewer. The volley discharge of waste liquid through the riser leads to the failure of the part. If the diameter is insufficient, water fills the cross-section of the passage, forming a low pressure that draws the liquid out of the device along with it. The water seal goes into the system pipe, allowing the stench to enter the house.

Siphon breakdowns often occur due to careless handling of the equipment. After which it will need to be repaired or completely replaced. When the apartment is visited periodically, the water plug dries out and gases from the sewer enter the room. Causes of unpleasant odors also include freezing of water, contamination of ventilation, damage in the form of cracks and accumulation of debris in pipes. Each situation requires its own way to eliminate odor in the toilet.

No head on the fan pipe.

Conclusions and useful video on the topic

The video below explains the main sources of indoor odor and how to eliminate it.

A putrid smell in the house should not be tolerated: it not only irritates the sense of smell, but also contains gases and microorganisms harmful to the body. It is important to identify the source of sewer odor in the apartment as early as possible in order to eliminate it on your own or by involving specialists.

Tell us about how you dealt with negative sewer odor on your own. Please comment on the information we provide in the block below. Here, ask questions, share effective methods of combating odor, and post thematic photos.

Odor danger

The sewer smell is persistent. Absorbed by the fabric of upholstered furniture, wallpaper, food, and wardrobe items. It is difficult to remove; aromatic aerosols help little. Clothes remain smelly after several washes.

The air from the sewer is dangerous for those living in the apartment. It is saturated with methane and hydrogen sulfide - toxic gases produced by the breakdown of organic particles that are harmful to health. And a large accumulation of methane becomes explosive.

Molds that multiply in high humidity are also dangerous. Constant inhalation of fungal spores provokes allergies and asthma.