Know more

Our use of cookies

Cookies are a set of data stored on a user’s device when the user browses a web site. The data is in a file containing an ID number, the name of the server which deposited it and, in some cases, an expiry date. We use cookies to record information about your visit, language of preference, and other parameters on the site in order to optimise your next visit and make the site even more useful to you.

To improve your experience, we use cookies to store certain browsing information and provide secure navigation, and to collect statistics with a view to improve the site’s features. For a complete list of the cookies we use, download “Ghostery”, a free plug-in for browsers which can detect, and, in some cases, block cookies.

Ghostery is available here for free: https://www.ghostery.com/fr/products/

You can also visit the CNIL web site for instructions on how to configure your browser to manage cookie storage on your device.

In the case of third-party advertising cookies, you can also visit the following site: http://www.youronlinechoices.com/fr/controler-ses-cookies/, offered by digital advertising professionals within the European Digital Advertising Alliance (EDAA). From the site, you can deny or accept the cookies used by advertising professionals who are members.

It is also possible to block certain third-party cookies directly via publishers:

Cookie type

Means of blocking

Analytical and performance cookies

Realytics
Google Analytics
Spoteffects
Optimizely

Targeted advertising cookies

DoubleClick
Mediarithmics

The following types of cookies may be used on our websites:

Mandatory cookies

Functional cookies

Social media and advertising cookies

These cookies are needed to ensure the proper functioning of the site and cannot be disabled. They help ensure a secure connection and the basic availability of our website.

These cookies allow us to analyse site use in order to measure and optimise performance. They allow us to store your sign-in information and display the different components of our website in a more coherent way.

These cookies are used by advertising agencies such as Google and by social media sites such as LinkedIn and Facebook. Among other things, they allow pages to be shared on social media, the posting of comments, and the publication (on our site or elsewhere) of ads that reflect your centres of interest.

Our EZPublish content management system (CMS) uses CAS and PHP session cookies and the New Relic cookie for monitoring purposes (IP, response times).

These cookies are deleted at the end of the browsing session (when you log off or close your browser window)

Our EZPublish content management system (CMS) uses the XiTi cookie to measure traffic. Our service provider is AT Internet. This company stores data (IPs, date and time of access, length of the visit and pages viewed) for six months.

Our EZPublish content management system (CMS) does not use this type of cookie.

For more information about the cookies we use, contact INRA’s Data Protection Officer by email at cil-dpo@inra.fr or by post at:

INRA
24, chemin de Borde Rouge –Auzeville – CS52627
31326 Castanet Tolosan CEDEX - France

Dernière mise à jour : Mai 2018

Menu Logo Principal RMT (Mixt Technological Network) Animal Farms and Environnement French Environment and Energy Management Agency logo "animal emissions" animal emissions

Animal Emissions

Guidelines for the measurement of air flow rate with CO2 balance in animal houses

figure_BilanT_H2O_CO2

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

File (PDF)