Carbon monoxide, commonly known as “silent killer” gas, is an odorless gas with highly toxic properties that, at room temperature, is completely undetectable by human senses. Since the heating season is already underway and many people heat their homes with gas heaters, the risk of carbon monoxide poisoning is increasing.
Where does carbon monoxide come from and why is it so dangerous?
It is a highly poisonous, colorless and odorless gas, slightly lighter than air, which means it mixes with air easily and spreads through it. It is produced by the incomplete combustion of many fuels, including wood, oil, gas, gasoline, kerosene, propane, coal and crude oil, caused by a lack of the oxygen necessary for complete combustion. This may result from an insufficient supply of fresh (outside) air to the appliance where combustion takes place, due to contamination, wear or incorrect adjustment of a gas burner, as well as premature closing of a furnace or stove firebox. This is particularly dangerous in homes where windows are tightly closed or sealed for the winter. Carbon monoxide is also often produced during fires.
The danger of carbon monoxide poisoning stems from the fact that the gas cannot be detected by humans. It enters the body through the respiratory system and is then absorbed into the bloodstream. In the respiratory system, carbon monoxide binds to hemoglobin 210 times faster than oxygen, blocking the supply of oxygen to the body. This poses a serious threat to human health and life. It prevents oxygen from being properly distributed in the blood and causes damage to the brain and other internal organs. Acute poisoning may result in irreversible damage to the central nervous system, coronary insufficiency and heart attack, or even death.
How can poisoning be prevented?
The primary cause of poisoning is incomplete combustion, which may occur, for example, when windows are closed too tightly and there is no proper ventilation. This causes carbon monoxide to form and obstructs its removal. As much exhaust gas will flow outside as fresh air flows into the room. Above all, it is therefore necessary to ensure a constant supply of fresh air to the firebox (gas heater, gas stove, coal stove or furnace) and the unobstructed discharge of exhaust gases.
Remember to:
- open a window slightly in the home when using any source of fire (a gas heater with an open combustion chamber, a gas stove or a coal stove)
- do not cover ventilation grilles or air-intake openings
- use the services of a qualified person when installing heating appliances and systems
- have ventilation systems and chimney flues periodically inspected and cleaned (when using coal and wood, this should be done at least once every 3 months; when using natural gas or heating oil, at least once every six months. The building manager or owner is required, among other things, to have the ventilation system inspected at least once a year)
- use technically sound appliances in which combustion takes place, in accordance with the manufacturer's instructions; check the technical condition of heating appliances
- use appliances with the appropriate approvals for placing them on the market; in doubtful situations, request the declaration of conformity issued by the appliance's manufacturer or importer, i.e. a document containing information on the technical specifications, intended use and scope of application of the appliance
- when replacing windows with new ones, check that the ventilation works properly, because new windows are usually much more airtight than those previously used in the building and may worsen ventilation
- regularly check the air draft, for example by holding a sheet of paper against an opening or ventilation grille; if nothing is obstructing the ventilation, the sheet should stick to the opening or grille
- frequently ventilate the room where combustion takes place (kitchens and bathrooms equipped with gas water heaters), and preferably ensure that the windows are slightly open, even if only through a small gap
- place carbon monoxide detectors in the part of the house where your family sleeps. For greater safety, additional detectors should be placed in every room; do not burn charcoal indoors, in a garage, on an enclosed porch or in similar places unless they have adequate ventilation
- do not leave a car running in the garage, even if the garage door is open
- do not ignore symptoms such as shortness of breath, headaches and dizziness, nausea, vomiting, confusion, weakness, or an accelerated heart rate and breathing, as they may indicate carbon monoxide poisoning; in such a situation, immediately ventilate the room you are in and seek medical advice.
What are the symptoms of carbon monoxide poisoning?
- headaches
- dizziness
- general fatigue
- shortness of breath
- difficulty breathing
- rapid, irregular breathing
- drowsiness
- nausea.
The weakness and exhaustion experienced by a person suffering from carbon monoxide poisoning, together with impaired orientation and the ability to assess danger, make the person completely passive (they do not escape from the area where the poison has accumulated), lose consciousness and, if no one comes to their aid, die.
How can you help someone suffering from carbon monoxide poisoning?
- immediately ensure a supply of fresh, clean air
- move the injured person to a safe place, into the fresh air, as quickly as possible
- loosen the injured person's clothing, but do not undress them, as they must not be allowed to become chilled
- call the emergency services (ambulance service – tel. 999, fire service – tel. 998 or 112).
- if the poisoned person is not breathing after being taken into the fresh air, immediately begin artificial respiration and cardiac massage.
Safe use of gas instantaneous water heaters
Gas is a widely available energy source commonly used in households. The tightness of a gas installation is an obvious condition for safe use, since a gas-air mixture may explode. However, most gas users do not know when there may be a risk of carbon monoxide poisoning (commonly known as “silent killer” gas). In Poland, around 100 people die each year from carbon monoxide poisoning caused by gas instantaneous water heaters, while several times more suffer poisoning requiring hospitalization.
The vast majority of fatal accidents occur between November 1 and March 31, during the cold season. Closed, airtight windows are the cause. The formation of carbon monoxide and its penetration into homes can easily be prevented by meeting four basic conditions for the safe use of gas-burning appliances. They are:
- proper installation
- a constant supply of fresh air
- unobstructed discharge of exhaust gases
- proper use ensuring that the gas appliance remains in good technical condition.
Proper installation
A gas heater may be installed or replaced only by an authorized specialist, in accordance with the manufacturer's instructions. Installation and adjustment work performed by an unauthorized person may pose a threat to the health and lives of residents. The same requirements apply to installation and adjustment work on gas stoves. The stove should be located as close as possible to the exhaust ventilation grille, and the work surfaces should be positioned between the window and the stove so that fresh air flows above them.
A constant supply of fresh air
A constant supply of fresh (outside) air to the appliance where gas combustion takes place is essential. A lack of fresh air causes oxygen deficiency. This deficiency results in incomplete combustion and the formation of carbon monoxide. This happens, for example, when the windows of the home are tightly closed. A constant supply of fresh air to the home is also necessary for the unobstructed discharge of exhaust gases. Therefore, remember to ventilate the bathroom thoroughly before every bath, equip airtight windows with air vents, and keep a window or transom slightly open in the home while bathing. Covering ventilation grilles—both the intake grille in the bathroom door and the exhaust grille at the entrance to the ventilation duct—poses a risk of fatal poisoning.
Unobstructed discharge of exhaust gases
A gas heater should be tightly connected to the flue, and the flue must be tight and unobstructed. An unsealed chimney weakens the draft or may cause exhaust gases to enter adjacent rooms. Chimney ducts (smoke, exhaust and ventilation ducts) must be inspected in accordance with applicable regulations. The inspection should be carried out by authorized persons, and the owner or manager is responsible for having the building inspected. However, unobstructed discharge of exhaust gases requires not only a clear flue but also a constant supply of fresh air to the room where gas combustion takes place. Exhaust gases will not be discharged if a gas heater in operation is located in a closed, sealed home. A constant supply of air to the room where the gas heater is switched on is therefore necessary to meet two basic safety requirements: complete combustion of gas and unobstructed discharge of exhaust gases. Do not switch on a fan in the kitchen or elsewhere in the home while bathing, because its operation weakens the natural exhaust draft in the gas heater's flue.
Good technical condition of the gas appliance
Gas appliances should be kept clean and in good technical condition, and periodically inspected in accordance with the manufacturer's recommendations. The obligation to maintain gas appliances in the required technical condition and make them available for inspection is imposed on the occupant of the premises by the Regulation of the Minister of the Interior and Administration of August 16, 1999, on the technical conditions for the use of residential buildings (Journal of Laws No. 74 of September 9, 1999, item 836, § 17(1) and (2)).
For the safety of themselves and their family, every user of gas appliances should feel responsible for this obligation. A gas heater that has been used for many years should be reported for inspection without delay. An old, worn, uncleaned and improperly adjusted gas heater poses a threat to life. Repair and maintenance of a gas appliance may be entrusted only to persons with the appropriate qualifications.
Your health and life, as well as those of your loved ones, may depend on following the advice above. A little precaution is all it takes!
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