The vast majority of CEAA assessments are screenings. While the term "screening" may suggest a cursory review, screenings involve the systematic assessment of environmental effects and mitigation measures in order for a responsible authority to make a decision on the significance of environmental effects and whether or not to take action in support of the project.
All projects are subject to a screening unless they are identified on the Comprehensive Study List Regulations. Projects on the Comprehensive Study List Regulations are typically large-scale undertakings and for this reason a more intensive assessment is required.