Carbon Monoxide Poisoning Symptomsby Laura Ginn Writer
Concerns about gas safety usually focus on the dangers of gas explosions. While gas is flammable, of course, and can cause an explosion under certain conditions, the larger gas safety issue is actually carbon monoxide poisoning. Unlike town gas (also called coal gas), distilled from coal and in common use in the United Kingdom until the 1960s, modern natural gas has been purified and processed to rid it of contaminants. In fact, gas delivered to end-users in the United Kingdom is pure enough that traces of tert-Butylthiol (t-butyl merceptan) or thiophane are added to provide an odor similar to that of rotten eggs, as a safety measure to warn of a gas leak.
The danger from carbon monoxide arises as a by-product from the process of combustion. Although gas is one of the cleanest-burning fossil fuels in common use, it does produce some chemical products during combustion. Even under the most efficient conditions, burning gas produces approximately 40 parts per million (ppm) of carbon monoxide (CO, in chemical nomenclature). This level increases when the combustion is only partial, such as occurs when the gas jets of an oven, stove top, heating grate or other gas appliance is dirty or damaged. The concentration of this colorless, odorless gas (the tell-tale odor-producing chemicals are destroyed during combustion) can reach much higher levels during incomplete combustion, particularly if the space is not properly ventilated.
Carbon monoxide molecules can, when breathed, cause damage and eventually death. As one atom of carbon connected to one atom of oxygen, the CO molecule bonds readily with red blood cells (hemoglobin) and myoglobin (the oxygen-carrying protein in muscle tissues), replacing oxygen molecules. As a result, the body can become starved of oxygen, causing asphyxiation, brain damage and interference with muscle activity, including heart failure. Even at relatively low levels of CO in the atmosphere, at 35 ppm, a healthy adult can begin to feel a slight headache as the brain is deprived of a percentage of its oxygen.
If the ventilation of a space – such as a kitchen or living room – is not sufficient to dissipate the CO gas being produced, the concentration can reach deadly levels. At concentrations above 800 ppm, a healthy adult will begin to experience nausea and even convulsions in less than an hour and, within two hours, can pass out. At twice that level, or 1,600 ppm (which is only a miniscule 0.16% of the entire atmosphere), death can occur within two hours. As the concentration of CO climbs even higher, anyone continuing to breathe this colorless, odorless gas will die; the greater the concentration, the sooner death will occur.
Acute CO poisoning usually occurs during structure fires, when concentrations of CO (and other deadly gases) can rise quickly to very high levels. Even if a person exposed to these high levels of CO is rescued before death occurs, there are long-term health consequences. Short-term memory loss, confusion, amnesia (memory loss of previous events) and dementia are all related to the consequences of oxygen starvation to the brain. As dramatic as these events are, the dangers of chronic (long-term) CO poisoning at lower concentrations can also be devastating to human health. Living or working in an area with even one one-hundredth of one percent concentration of CO – just 100 ppm – can cause a continuous headache, confusion, memory loss and mental depression. Due to the affinity of muscles’ myoglobin to bond with CO instead of oxygen, individuals with a history of heart disease are in danger of further heart damage. Pregnant women and their unborn children are also in danger of harm to their health.
The most dangerous aspect of CO poisoning is that, typically, less than 30% of people subjected to dangerous levels of this gas even show any recognizable symptoms. It is possible for someone to live or work for years in a building with high CO levels without realizing that anything is amiss. For that reason, it is considered to be an important part of public health programmes to ensure that all buildings using gas appliances – from gas furnaces to ovens – to have carbon monoxide detectors. Anyone living in a structure considered to be at risk for CO poising can easily be tested with a non-invasive pulse co-oximeter. This simple device, clipped to the end of a fingertip, passes wavelengths of light through the tissue to measure the oxygen levels in the body.While gas appliances are modern conveniences found throughout the country, they can present the possibility of a health hazard. Being aware of the dangers of carbon monoxide poisoning is an important part of gas safety.
Laura Ginn appreciates that all home owners should be aware of the effects of carbon monoxide poisoning as part of their general gas safety awareness. Using the energy saving tips and guides on uSwitch you can find out everything you need to know to stay up to date on gas safety.
Created on Dec 31st 1969 19:00. Viewed 0 times.