Life Cycle Impact Assessment and Results

What are Areas of Protection (AOPs)?

The overarching categories of value that environmental impacts can damage: Human Health, Natural Environment / Ecosystem Quality, Natural Resources

What impact category is associated with (kg Sb_eq/kg)

Depletion of Abiotic Rescourses

What impact category is associated with (m² year)

Land Use Competition

What impact category is associated with (kg CO_{2 eq}/kg)

Global Warming

What impact category is associated with (kg CFC-11/kg)

Ozone Depletion

What impact category is associated with (HTP)

Human Toxicity

What impact category is associated with (kg 1,4-DBC(C₆H₄Cl₂)/ kg)

Eco-toxicity

What impact category is associated with (kg C₂H₄/ kg)

Photochemical Ozone Creation

What impact category is associated with (kg SO_{2 eq}/kg)

Acidification

What impact category is associated with (kg PO₄^3-/kg)

Eutrophication

How are impact calculated?

It is calculated by the sum of the multiplication of a characterization factor with the matching emission.

∑ CFi × Qi

What is a midpoint indicator in life cycle impact assessment and what is an endpoint indicator?

Midpoint → Indicates the early effects in the cause-effect chain

Endpoint → Indicates the damage to selected areas of protection, later in cause-effect chain

Example: Emission of CO₂

Midpoint: Change in the atmosphere's ability to absorb infrared radiation

Endpoint: Measures the damage caused by global warming, such as human casualties from heatwaves

What are the common strategies for the selection of life cycle impact categories?

The Shotgun Approach → Includes all impact categories that are part of a given method

The Sniper Approach → A short list of targeted impact categories is selected, relevant to the question the LCA wishes to answer

What are the advantages and disadvantages of the Shotgun approach?

Advantage: The risk to miss out on unexpected impact is decreased

Disadvantage: Showing all of these results may overwhelm the audience

What are the advantages and disadvantages of weighting?

Advantages: Helps to resolve trade-offs and ease interpretation and communication

Disadvantages: Includes value judgement and it is barred in the ISO standard for “comparative assertions disclosed to the public”

What are the three principles of weighing for environmental impact categories?

Economic information - The impacts are monetized by willingness to pay or market surveys

Distance to target - Targets may be set by social entities or nature (critical loads on what a ecosystem can carry)

Priorities as expressed by panels - May be based on preference or opinions of experts or of lay people

When different parts of a production process are not included in impact results, what type of analysis cannot be used?

Dominance analysis: This analyzes the contribution of the different processes in a system

If the results of several impact categories show a similar trend is it enough to communicate just one impact category?

No, one might miss out on an important impact or even a burden shift

What do the negative values in the results indicate?

Processes that create an environmental credit for the system. They reduce the environmental impact of the system analyzed. This is due the the fact that the processes have a lower environmental impact than the process they replace.