Carbon Monoxide Alarm
Carbon monoxide is a toxic gas which has no color and odor and due to such characteristics it is almost impossible to detect the presence of carbon monoxide without using carbon monoxide alarms or detectors. Even a small amount of the gas can lead to serious health hazards as it accumulates in the blood and reduces its oxygen carrying capacity. Carbon monoxide is produced when fossil fuel is burned. An adequate amount of ventilation during the combustion process leads to a very small quantity of carbon monoxide being produced. However, incomplete combustion of fossil fuel, due to insufficient airing, would result in large volumes of carbon monoxide production.
Burning of any carbon containing substance will result in carbon monoxide production, e.g. wood, coal, kerosene and charcoal emit carbon monoxide when reacting with oxygen in the air. Maximum amount of carbon dioxide is produced during a cold engine startup, thus starting an engine and idling it in a closed space, like a garage, can lead to an alarming situation. Fumes containing carbon monoxide then passes into the house through the walls and any opening, rapidly crossing the safety limit.
Although proper ventilation and regular maintenance checkup of burning equipments and spaces, reduces the threat of carbon monoxide poisoning greatly, but one can never be 100% safe from it regardless of the best maintenance procedure. Especially for houses near the road, carbon monoxide produced outside by heavy traffic can affect the air composition inside the houses. This is where carbon monoxide alarms come in with the objective of detecting the level of carbon monoxide present in the air to prevent health risks. The basic operation of the alarm/detector is to measure the volume of the toxic gas over regular time intervals and set off an alarm before carbon monoxide builds up to a dangerous level thus allowing occupants to ventilate or evacuate if necessary. Carbon monoxide detector is the best safety precaution and in some places, the law specifies that a detector should be installed to avoid health hazards. Therefore it is recommended that every house should get at least one carbon monoxide detector, as high level of carbon monoxide outdoor can seep into the houses and cause carbon monoxide poisoning.
The detectors should be placed from where it can be heard during sleeping. Carbon monoxide has approximately the same density as air and it spreads out uniformly all through a room hence it could be located anywhere in the room providing that its alarm is audible from that particular location to any part of the house. The following is a list of place where carbon monoxide detectors should not be placed:
- In unheated parts of the house, such as attics and basements.
- Highly humid areas
- Where there is a chance of being exposed to chemicals contents present in cleaners, hair sprays etc.
- Near ventilation openings and chimneys
- Within 6ft radius of heaters and cookers
- Where there is direct exposure to the outside weather
Three types of sensors are available for carbon monoxide detectors, namely, biomimetic, metal oxide and electrochemical sensors. Each has a set of features which is different from the others and each works in a different way from the other two.
- Biomimetic sensors: These are disk like structures coated with a gel of synthetic hemoglobin which changes colors to notify the gas’ presence. The change in color triggers the alarm. These sensors can be operated with battery and are comparatively less expensive than metal oxide and electrochemical sensors.
- Metal Oxide sensors: These were the first type of sensors developed to detect carbon dioxide. The sensor is a tin oxide which when heated reacts with carbon monoxide gas and thus determines the level of the gas present in the surrounding environment. Detectors containing metal oxide sensor are directly connected to the power supply of the house and has a backup battery which can provide uninterrupted support of 20 hours.
- Electrochemical sensors: These sensors allow the carbon monoxide to react chemically and produce a large pulse of current which sets off the alarm. The electrochemical sensors are well known for their high sensitivity and accurate readings.
The following is a list of features one should take into account before buying a carbon monoxide detector.
- Detectors should have logos of authentic testing agencies
- If long term low level exposure is to be monitored, a detector with an in-built memory should be chosen.
- Detectors run by batteries, give its users the freedom to locate at areas of the room which they think to be most convenient, but they also they users to regularly check the battery life.
- Detectors should not be plugged into switch controlled electrical inputs.
- The sensor life for most detectors is approximately 5 years. The sensors should be replaced at least once in five year duration.
Although, it is only large volumes of carbon monoxide which is considered to be a threat, exposure to low levels for a long time can cause health problems too, particularly for young children and those with respiratory problems. Thus it is sensible to buy detectors which are equally effective in measuring both low and high levels of carbon monoxide presence, despite being expensive. Because at the end of the day, it is a safety precaution device and safety of the family members cannot be compromised with price.
