Resource centre for greenhouse gas accounting
Ministère de la Transition Écologique
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A GHG assessment is an evaluation of the quantity of emitted (or captured and stored) GHGs in the atmosphere over one year resulting from the activities of an organization or a territory.

The emissions of the entity are classified according to predefined "categories". This classification makes it possible to identify the emission categories where the carbon impact is greatest. It is on these categories that the entity conducting its assessment needs to focus its energy and environmental strategies for reducing emissions.


Conducting your GHG assessment allows you to:

  • Structure your environmental policy
  • Identify actions enabling your energy bill to be reduced along with its global impact
  • Evaluate your vulnerability
  • Stand out through setting an example
  • Comply with regulations (if subject to them)
  • Involve your employees or partners in the exercise

Depending on the objective sought by the organization, a GHG assessment may be approached in different ways.

It is generally associated with a project and actions for reducing emissions. When carried out over a broad emissions scope, the GHG assessment enables to evaluate the carbon dependency and vulnerability of an organization, and may facilitate reflection about the enterprise development strategy.


The methodological principles relate essentially to two points:

  • the scope of the emission sources to be taken into account
  • the data to be used

These principles will vary considerably depending on the type of assessment that is carried out. For more detailed information about the methodological principles, you may refer to the pages dedicated to:

  • GHG organizational reporting (companies, collectivities, public establishments)
  • GHG reporting for territories

All the methodological principles presented are based on the ISO 14064-1 standard.


Which boundaries to choose?

The selection of the scope of study depends on the intended target of the assessment (environmental policy of the organization, regulatory requirements, carbon vulnerability, etc.), as well as on the available resources of the organization for carrying out the GHG assesmnet and implementing relevant actions.

The organization will need to consider two types of boundaries before assessing its emissions:

  • Whether or not take into account all the entities relating to its structure (subsidiaries, establishments located on other sites, activities for which the structure is responsible, etc.). This pertains to the organizational boundary.
  • Whether or not to take into account all emissions generated by the activity, be they emitted directly or indirectly. This pertains to the reporting boundary.

Outside of the regulatory framework, these boundaries choices are left to the discretion of the organization.

Which data to use?

To implement a GHG assessment, it is necessary to gather all the activity data for the organization being studied. This may concern information that is already available within the organization (primary data), but also external data to be collected from suppliers, customers, users, etc., or indeed statistical or study data (generic or secondary data).

These are the data that can be used for completing the spreadsheets for the chosen method. These data will then be associated with an emission factor enabling calculation of its carbon equivalent. These emission factors are available in the Base Carbone®.


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