## 3 Results
### Life Cycle Impact Analysis
In Scenario 2, Climate Change, Fossil Depletion, Ozone Depletion, Water Depletion, and Agricultural Land Occupation categories showed the lowest environmental burdens when compared to Scenarios 1 and 3. In Scenario 3, the best environmental performance was observed in the impact categories of Human and Ecosystem Toxicities, Marine and Freshwater Eutrophication, Terrestrial Acidification, Metal Depletion, Photochemical Oxidant Formation, Ionizing Radiation, Particulate Matter Formation, and Urban Land Occupation, when compared to Scenarios 1 and 2. Comparing Scenarios 2 and 3, it is observed that Scenario 3 allows a further reduction of the values of impact in 13 categories out of 18 analysed when compared to Scenario 2. The reduction percentages vary from 28% (Metal Depletion) to 993% (Natural Land Transformation). The results of the environmental impacts obtained in Scenario 1 for the present case study are in good agreement with those reported in the literature for the diamond multi-wire/circular saw (DMWS) [18], where the impact values in the categories Climate change, Ozone depletion, Water depletion, Particulate matter formation, Photochemical oxidant formation, Freshwater, and Terrestrial eutrophication are almost in the same order of magnitude of those obtained in this work, even if different methodologies of calculation were used (Recipe 2016 in this work vs. ILCD in the bibliographic reference [18]). The small difference observed between the present work and similar works [13] for the water depletion, from values of 2.48 kg/m\({}^{2}\) granite slab, obtained in the present work, to an average value of 11.1 kg/m\({}^{2}\) reported in the literature [3,18], demonstrates higher efficiency of the sawing equipment considered in this work towards the natural water depletion category. It must be noticed that the Natural land transformation category is favoured by GS disposal into landfills since the avoided extraction of inert filler, as well as of feldspar, are responsible for greater changes on natural land. Among the 18 environmental indicators analysed, applying the weighting function, which allows ranking the impact categories according to the damage they can trigger in human health, ecosystems, and resource depletion, those that contribute the most are particulate matter formation, human toxicity, fossil depletion, climate change, and natural land transformation (Figure 4a-e). The category of fine particulate matter formation is affected by a percentage of 99.77% in Scenario 1 by stone sawdust formation during granite cutting, which produces approximately 1.3 kg of fine particulates per m\({}^{2}\) of granite slab. Small and insignificant environmental credits (<0.5%) are provided by the avoided feldspar or inert filler production considered in Scenarios 2 and 3 in this impact category. The formation of fine particulate matter, besides an environmental issue, must be addressed as a health and safety risk for workers, who are recommended to wear FFP2-3 masks, as well as guarantee the regular cleaning operation of the workspaces and perform regular medical surveillance for respiratory disease control (Figure 4a). Regarding human toxicity, Scenario 3 is the one that provided the lowest environmental burden due to the credits generated by the avoided generic market for inert filler and by avoided inert filler transport. These credits account for \(-209\%\) of the total value of human toxicity since \(-142\%\) are due to transport and the remaining\(-67\%\) to sand extraction and processing. They allow a reduction of human toxicity by a percentage of 93% when compared to Scenario 1. The worst environmental performance of Scenario 1 is due to a percentage of 7.9% to electric energy consumption (PT mix), whereas 90.8% is associated with the treatment of GS to sanitary landfill (Figure 4b). No significant credits are obtained by the avoided feldspar production considered in Scenario 2 in the Human toxicity impact category.