In many instances, the means to sense gaseous CO2 levels and to activate carbon dioxide alarms, should those levels become unsuitable for a given task or environment can prove invaluable. In fact, the applications for this type of technology are apt to appear almost unlimited. In addition to playing a pivotal role in a wide range of industrial and commercial processes, one of the most important uses for this technology lies in the continuous monitoring and adjustment of indoor air quality (IAQ), both within as well as in the immediate vicinity of a building. In the absence of such oversight, these levels could pose a serious risk to the health and safety to the occupants.

Even though the gas is exhaled by all animal life in significant quantities, our senses cannot detect CO2 unassisted, so carbon dioxide alarms linked to specialised sensors are required, in order to alert people to the risk of excess atmospheric concentrations. Even at levels of just 1 part per thousand, one’s ability to concentrate is affected and the recognised international safety limit has been set as 0.5%. Symptoms intensify with rising levels, headaches occurring at around 2% and increased respiration and blood pressure at the 3% mark, followed by choking and eventual asphyxiation as levels approach 10%.

The biggest danger to humans lies in poorly ventilated, confined spaces. In pubs, for instance, the gas is used to pump draught beverages and to add the fizz. The dispensing equipment is often used in small, unventilated cellars, making the use of CO2 sensors and carbon dioxide alarms vital to the safety of personnel responsible for changing the barrels. The process involves disconnecting and reconnecting the gas lines and so carries the risk of heavy leakages that could lead to toxic levels in the ambient air.

The sensors in question employ one of two alternative principles, making use of either an infrared source or chemical interactions between the gas and a layer of reactive material. Non-dispersive Infrared (NDIR) sensors are most commonly used for measurement of the gas as used in the manufacture of carbonated drinks and in many of the fermentation processes employed by the pharmaceutical, brewing and winemaking industries. Although more expensive and less compact than their chemical counterparts, the infrared sensors are more robust and eliminate the drift that results in inaccurate CO2 readings, causing carbon dioxide alarms to be activated inappropriately.

As stated earlier, the uses for this technology are manifold. Innovative and, in some cases, even bizarre new applications, such as providing a major advance in the detection of stowaways or intruders by their exhalations, are constantly being added. Other common areas in which these devices are proving to be indispensable are the monitoring of landfill gas concentrations, cryogenics and building management.

IEPSA is a leading supplier of analytical and scientific equipment to medical, educational and industrial establishments around South Africa. Aware of the need for quality and reliability, we ensure that all of the products we offer are thoroughly tried and tested, and sourced only from the most reputable international manufacturers in Europe, the United Kingdom and the United States.

Analox Sensor Technology is a recognised specialist in this field, from whom we import both fixed and portable CO2 sensors and carbon dioxide alarms.

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