For industry out of waste management, the observed and surveyed unit is the establishment, in fact, is the closest to the expense and better located unit.
Regarding the waste management sector, the observed and surveyed unit is the legal unit. Indeed, preliminary tests for the survey have shown that for this sector the information was available at entreprise level.
Since the observation year 2009, the survey is conducted by internet (a paper questionnaire can be sent on request). More than 80% of the surveyed establishments do respond.

For more information: see methodological note