Click on 'Requirements' on the left hand side of the page.
Click on 'Settings' under 'Requirements' on the left hand side of the page.
Click on the pencil next to the Requirement that you would like to edit.
Scroll down to the 'Advanced' section and click to expand.
Once expanded scroll down to the Departments section.
To add the Requirement to the Department select the Department from the Available list and click on the single arrow > to move it over to the Selected list. If this Requirement should be assigned to all of the Departments simply click on the double arrows >> to move them all from the Available to the Selected list.
To remove the Requirement from the Department select the Department from the Selected list and click on the single arrow < to move it over to the Available list. If this Requirement should be removed from all of the Departments simply click on the double arrows<< to move them all from the Selected to the Available list.