Introduction

The air flow measurement by CO₂ balance is a good alternative to the air flow measurement in an animal housing when this one is not realizable, like the naturally ventilated buildings. The goal of this method is to control the CO₂ gradient between the inside and the outside of the house. This method does not give extremely precise measurement because of CO₂ variations related to the animal activity. It can nevertheless be modelled to improve the accuracy of the results. It is possible to take these measurements over one day, half-day or when the variations in CO₂ production are negligible.

The principle of measurements is identical to the tracing one. It is supposed that ventilation explains the relation between the production of CO₂ and the CO₂ gradient, and one deduced that the rate of ventilation equalizes the ratio of the CO₂ gradient by the theoretical production of CO₂.

Equipment

Depending on discontinuous or continuous measurements, the equipment will vary.

One can refer to the procedures "masse balance" or "tracing" for respectively discontinuous or continuous sampling.

In any cases, it is recommended to use equipment for the measurement of air temperature and humidity, and to measure the concentration in CO₂ inside and outside the house (inlet and outlet when the house does not exchange directly with outside the house).

Guideline details

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