A contractor compares enough concrete blocks and natural stone blocks to pave the same area. The contractor measures only the mass of waste produced during manufacture and concludes that the natural stone blocks have a lower environmental impact.
What is the main limitation of the contractor's evidence?
The blocks cannot be compared because they are made from different raw materials.
The assessment should replace the measured waste data with a value judgement about each material.
The data cover one environmental impact at only one stage of each product's life cycle.
The comparison should use one kilogram of each material instead of the blocks needed for the same area.
99 exam-style questions on AQA GCSE Chemistry 10.2 Life cycle assessment and recycling, covering 10.2.1 Life cycle assessment and 10.2.2 Ways of reducing the use of resources. Each one has a worked solution and a mark scheme showing where the marks go.