A portable carbon monoxide detector operates on a trigger-based alarm system that identifies whether there is an accumulation of carbon monoxide in a particular area over an indicated duration of time. Specifically, these carbon monoxide detectors use several types of sensors to sense carbon monoxide within the air.
Biomimetic sensors are most commonly placed on portable carbon monoxide detector cards. This type of sensor reproduces the effect of carbon monoxide when it comes into contact with haemoglobin in the blood. The colour of the card turns into a darker hue when it absorbs carbon monoxide.
An alternative type of carbon monoxide detector is one that uses a metal oxide as the semiconductor. This metal oxide sensor (MOS) is composed of a sensitive film that is made of tin or tungsten oxides. The film reacts with gases and when a high level of carbon monoxide is detected, the circuits within the sensor lower the electrical resistance to produce an alarm.
Some types of carbon monoxide sensors such as electrochemical sensors are able to detect dangerous levels of carbon monoxide instantly. These are often used in professional sensing equipment. The electrodes immersed in a chemical solution are used to detect changes in the flow of electric current and give off warning signals.
A portable carbon monoxide detector is an interesting piece of equipment. Although there are variations to designs, detectors contain a small silicon microchip which sends an electronic charge that functions as a signal to the other parts of the detector. Light-emitting diode (LED) indicators or liquid crystal display (LCD) panels serve as the main screen that flashes when the carbon monoxide reaches an extremely high level. Wires may or may not be connected to the building’s electrical system but for most portable types, a battery is enough to provide power. A detection chamber or sensor inlet measures the carbon monoxide gas concentration in the area in parts per million (ppm).
These digital portable carbon monoxide detectors are usually a better choice for real time “on the go” applications. These respond to high levels of CO instantly, allowing a person to address his situation to avoid more serious injuries.