What is CO2?
CO2 is a naturally occurring gas that is found in the earth’s atmosphere. It is invisible, odorless and 50% heavier than Air. CO2 is a main product from combustion processes and from the natural metabolism of living organisms.
Humans inhale oxygen and exhale carbon dioxide. The CO2 level in exhaled Air is rather constant about 3,8 % (38.000 ppm). When CO2 is exhaled, it will quickly be mixed with the surrounding air and, provided that the ventilation is good, the concentration will be reduced to harmless levels. Indoor CO2 levels usually vary between 400 and 2000 ppm (parts per million). Outdoor CO2 levels are usually 350 – 450 ppm depending largely on the season. Heavily industrialized or contaminated areas may periodically have a CO2 concentration of up to 800 ppm. The levels of outdoor CO2 are higher in areas where traffic is very heavy.
CO2 is produced by breathing, fires, cars, inaccurate mixing of detergents and fermentation. CO2, in spite of not being classified as a toxic in itself, is an insidious gas. It is harmless in small quantities but in high concentrations it is fatal. Because the gas is odorless it cannot be detected without measuring instruments and many fatal accidents have occurred in e.g. beer cellars and in modern restaurants with large quantities of CO2 being used for production of soft drinks. As well as in other locations where CO2 is used to treat water.
CO2 must not be confused with Carbon Monoxide (CO), a very toxic gas that is a by-product from poor combustion in i.e. cars and fireplaces. Carbon monoxide is dangerous at very low concentrations (25 to 50 ppm).
What is CO2 used for?
CO2 is presently the fastest growing general used gas in the world, with a wide variety of applications ranging from refrigerant in cooling systems, balancing Ph in swimming pools, freezing food-stuff, industrial cleaning, Dry Cleaning (Dry Wash) and as an additive in food, carbonizing drinks and numerous other applications.
Indoor CO2 measurement provides a dynamic measure of the balance between CO2 generation in the space, representing occupancy and the amount of low CO2 concentration outside air introduced by ventilation. Few gases have such varied areas of application as CO2. Interest and demand for the gas is strongly increasing. This is mainly a result of its proving to be the most environmentally friendly alternative to many different hazardous substances used in today’s modern society. New legislation has been introduced insuring safety.
CO2 is used in most modern Slaughter houses to gas the animals. It is considered by many as a humane method for “stunning” the animals.