# Environmental Impact Specification
As discussed in the Step-by-Step guide to Environmental Impact, global environmental impact parameters may be specified in the Environmental Impact Specification dialog.
Global environmental impact parameters are listed for each material type. Highlighting a material type and clicking Edit (or double-clicking the material type) opens the Environmental Impact Wizard for that material type.
The reinforcement % for environmental impact is used to combine the concrete values with the rebar values in determining values for reinforced concrete.