Life Cycle Assessment Software for Product and Process

Article pubs.acs.org/jchemeduc

Life Cycle Assessment Software for Product and Process Sustainability Analysis Marina Vervaeke* Centre for Corporate Sustainability (CEDON), HUbrussel, Stormstraat 2, 1000 Brussels, Belgium ABSTRACT: In recent years, life cycle assessment (LCA), a methodology for assessment of environmental impacts of products and services, has become increasingly important. This methodology is applied by decision makers in industry and policy, product developers, environmental managers, and other non-LCA specialists working on environmental issues in a wide variety of sectors. Especially for chemical engineers and scientists, it is essential to have an understanding of the LCAmethodology when developing new products. Performing an LCA is time intensive and the choices and assumptions made during system modeling, especially with respect to the system boundaries, the processes to include, the used technology, and geography are often decisive for the result of an LCA study. The outcomes of an LCA have to be analyzed in a critical way, especially if they are used for business decisions and policy making. Different scenarios have to be studied. Two examples are presented where LCA-software (SimaPro5) is used. The first one is a simple analysis of a coffee machine to obtain information on the environmental impact of the processes. The second one investigates different scenarios for waste treatment of paper and cardboard. KEYWORDS: Upper-Division Undergraduate, Environmental Chemistry, Collaborative/Cooperative Learning, Computer-Based Learning, Green Chemistry, Industrial Chemistry

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n recent years, concerns about climate change, increasing pressure on natural resources, and environmental pollution have brought sustainable development to the top of the political, social, and business agenda. Sustainable development was defined by the United Nation’s Commission on Environment and Development as “development that meets the needs of the present without compromising the ability of future generations to meet their own needs”.1 There are increasing legal, market, and financial pressures on manufacturing industries to develop sustainable products. Sustainable development requires methods and tools to quantify and to compare the environmental impacts of providing goods and services (“products”) to our societies. Every product has a “life”, starting from the design of the product, followed by resource extraction, production, use or consumption, and finally, end-of-life activities (collection, sorting, reuse, recycling, waste disposal). All activities, or processes, in a product’s life result in environmental impacts due to consumption of resources, emissions of substances into the natural environment, and other environmental exchanges (e.g., radiation).2 Life cycle assessment (LCA) is a methodological framework; today, it is one of the most widely used and internationally accepted methods for analyzing the environmental profile of products. An LCA is a calculation of the environmental burden of a material, product, or service during its lifetime.3 © 2012 American Chemical Society and Division of Chemical Education, Inc.

LIFE CYCLE ASSESSMENT

Structure and the Components of an LCA

LCA studies are based on scientific foundations and are carried out in conformity with the ISO 14040 series (ISO 14040−ISO 14044).4−9 These standards provide minimum requirements for the performance of an LCA and define the four basic stages for LCA studies: goal and scope definition, life cycle inventory analysis, life cycle impact assessment, and life cycle interpretation (Figure 1).1,2 The goal definition of an LCA provides a description of the goal of the study, as well as the reasons that have led to its realization, the kind of decisions that will be made from the results obtained, and if these will be of internal (for a company, for instance) or external use (to inform the general public or an institution). The scope definition describes the system, its boundaries (conceptual, geographical, and temporal), the quality of the data used, the main hypothesis, as well as the limitations of the study. A key issue in the scope is the definition of the functional unit. This is the unit of the product or service whose environmental impacts will be assessed or compared. It is often expressed in terms of amount of product or is related to the amount of product needed to perform a given function.2 The inventory analysis is a technical process of collecting data, in order to quantify the inputs and the outputs for all the processes within the boundaries of the product system, as Published: April 23, 2012 884

dx.doi.org/10.1021/ed200741b | J. Chem. Educ. 2012, 89, 884−890

Journal of Chemical Education

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Figure 1. Phases and applications of an LCA based on ISO 14040.4.

defined in the scope. Energy and materials consumed, emissions to air, water, soil, and solid waste produced by the system are calculated for the entire life cycle of the functional unit. To make this analysis easier, the system under study is divided into several subsystems, and the data obtained are tabulated in a life cycle inventory table for each stage in the product’s life cycle.2 Life cycle impact assessment is a process to identify and characterize the potential effects produced in the environment by the system under study.2,10,11 The starting point is the information obtained in the inventory stage. It consists of four steps: • The first step is classification, in which the environmental interventions (resources consumed, emissions to the environment) identified in the inventory analysis for every subsystem are grouped in different impact categories, according to the environmental effects they are expected to produce. Impact categories include climate change, stratospheric ozone depletion, photochemical ozone and smog formation, acidification, toxicological stress, the depletion of resources, water use, land use, noise, radiation, and so forth. For example, CO2, CH4, and N2O emissions are classified in the category “climate change” and C2H4, CH3COCH3, H2CO are classified in the category “smog”. • The second step, called characterization, consists of weighting the different substances contributing to the same environmental impact. For example, the relative contribution of different gases such as CO2, CH4, N2O to climate change are weighted and each expressed in kg eq CO2. The weighting factors are made available to practitioners in the literature, in the form of databases. The indicator score, expressed as global warming potential, for the impact category “climate change” can be calculated by summarizing the weighted data. At this point, the environmental profile of the system is obtained, consisting of a set of indicator scores, one for each impact category. • The third step is normalization of the indicator scores, which involves relating the environmental profile of the system to a broader data set or situation. For example, relating the system’s global warming potential to the European yearly global warming potential. As such, information is obtained on the contribution of a product to the total climate change for a certain geographical region. Normalization allows to compare indicators across impact categories and to choose between product alternatives, for example, to prioritize two products, one with a low climate change indicator and high toxicological indicator and another with a higher climate

change indicator and a lower toxicological indicator. Normalization results can help to judge the relative importance of different impact categories within an LCA study. • The last step is weighting. The environmental profile, expressed in a set of normalized indicators, is reduced to a single impact score by using weighting factors based on subjective value judgments. For instance, a panel of experts or public could be formed to weight the impact categories. The advantage of this stage is that different criteria (impact categories) are converted to a numerical score of environmental impact, thus, making it easier to make decisions. However, a lot of information is lost, and reality is simplified. Normalization, grouping, and weighting are not a requirement of ISO 14044:2006. A number of impact assessment methodologies are available to the LCA practitioner and several of them are implemented in software, commercially available on the market. Three frequently applied life cycle impact assessment methods are the Danish method “Environmental Design of Industrial Products 2000” (EDPI2000) and two Dutch methods “Ecoindicator 99” and “Life Cycle AssessmentAn Operational Guide to the ISO Standards 2001” (CML2001). The Ecoindicator 99 method has a damage-oriented or an end point approach, proceeding from the identification of areas of concern (damage categories) to the determination of what causes damage to these (impact categories). The Eco-indicator 99 method considers three damage categories: human health, ecosystem quality, and resources.12,13 The result obtained with the Eco-indicator 99 method is expressed as a single Ecoindicator score in eco-points (Pt) or milli-points (mPt). One eco-point can be interpreted as one-thousandth of the annual environmental load of one average European inhabitant. Interpretation is the last stage of an LCA study. The results obtained are presented in a synthetic way, presenting the critical sources of impacts and the options to reduce them. Interpretation involves a review of all the stages in the LCA process to check the consistency of the assumptions and the data quality, in relation to the goal and the scope of the study.2,11 Direct applications of LCA include product development and improvement, strategic planning, public policy making, and marketing (Figure 1).1,14 The general aim of an LCA is: • to provide an environmental evaluation, as complete as possible, of products and processes for the different phases of the life cycle; • to identify major environmental impacts and the life cycle stages or “hot-spots” contributing to these impacts; 885



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Figure 2. A simplified process chart for the life cycle of a coffee machine.

Figure 3. (A) Normalization and (B) weighting analysis of 0.1 kg virgin aluminum by Eco-indicator 99 (H) V2.06/Europe EI 99 H/A.

• to compare environmental impacts of alternative products, processes or activities; • to provide decision makers with information on the environmental effects of these activities and identify opportunities for environmental improvements. LCA can be applied by decision makers in industry and policy, product developers, environmental managers, and other nonLCA specialists working on environmental issues in a wide variety of sectors.15

Other processes show typical continental, national, or even regional characteristics, such as electricity generation, road transport, cement manufacturing, and agricultural production.2 To assist the inventory analysis, data have been collected in life cycle databases in a unit process. These data are used as building blocks in different life cycle models. The databases contain data on the most important processes (manufacturing, transportation, disposal, electricity and thermal energy generation, etc.) and materials (plastics, metals, biological materials etc.).2 Several international and national-level databases have been created that cover more commonly used goods and services. Software tools have been developed to make system modeling (process-chart) and calculation (inventory analysis and impact assessment) of an LCA easier and faster. The initial steps were taken about two decades ago, with the main focus often on the assessment of production processes. Over time, LCA-software also has been applied to other fields such as waste management. A software tool generally consists of a database and a graphical user interface where the data are handled, modeled,

LCA Databases and Software

Life cycles easily comprise hundreds of processes. The collection and compilation of data for the environmental exchanges between processes in the product system and the environment is often the most work- and time-consuming step in an LCA.1 Product systems usually contain process types common to nearly all studies; these are energy supply, transport, waste management services, and the production of commodity chemicals and materials. Because of global markets, many of these process types are similar or even identical (oil extraction in the Middle East, steel manufacturing in Asia, etc.). 886



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filters (3650) and the energy consumption can then be included based on this assumption. A simplified life cycle of the coffee machine is given in Figure 2. Only the polystyrene housing, the glass jug, the steel hot plate, and an aluminum riser pipe are included. Paper used for the production of filters and the electricity consumption needed to brew the coffee and keep the coffee hot are included. Other parts of the coffee machine, the coffee beans, and the water have been omitted. Assumptions about consumer behavior for the disposal stage are that the machine will be put in the trash and thus processed as municipal waste and that only the glass jug can be regarded as household waste. Some of the filters end up in the trash and some with organic waste. Such a process chart, with a quantity for each process on the basis of the functional unit, provides a useful insight for further analysis. The Eco-indicator 99 scores (Europe EI 99 H/A) are obtained by multiplying the amount by the indicator value for each process (Figure 2). For aluminum, for example, this is calculated as follow: 0.1 kg × 780 mPt/kg = 78 mPt. The process chart of the coffee machine can easily be built by selecting the processes in the database (in the required amount) and connecting them in the graphical user interface. Students are asked to analyze the processes “aluminum”, “steel”, and “polystyrene”, which are important basic materials for the production of this consumer good, and the process “electricity low-voltage” that represents the energy used by the coffee machine during its life time. For each of these processes, the database provides a detailed description of the used technology, cutoff rules, allocation rules, transport and energy model, and information about the end of life waste treatment. The inventory table illustrates the inputs and outputs for the amount of product or energy selected and outputs for the amount of product per energy selected and is the base for classification, characterization, normalization, and the final step weighting to obtain the Eco-indicator. The calculated results for characterization, normalization, and weighting are presented in tables and graphs. The results for normalization and weighting of 0.1 kg virgin aluminum are illustrated in Figure 3. Important impact categories for the production of aluminum are the emission of inorganic substances (31 mPt) and the extraction of fossil fuels (26 mPt). Figure 4A illustrates the Eco-indicator value for 0.1 kg virgin aluminum. In the second part of the assessment, the students compare and evaluate alternative processes for the aluminum production and the electricity low-voltage. They are asked to look for alternatives to make both processes more environmental attractive. Figure 4B illustrates the Eco-indicator value for the production of 0.1 kg 100% recycled aluminum, which is much lower compared to virgin aluminum. Thereto the students receive the essential information about the different industrial production processes of aluminum.17−21 The low-voltage electricity Eco-indicator in this model has a value of 10.3 mPt/MJ and represents the environmental load resulting from the production of low voltage electricity in The Netherlands (time period 1990−1994, average technology, mix of fossil fuels, renewable sources, and nuclear sources). When the coffee machine is used in Switzerland, a country where hydroelectric power accounts for about 60% of the total electricity production, the Eco-indicator value is reduced to 2 mPt/MJ.

and analyzed, following the ISO 14040 series recommendations. The modeling consists mainly of connecting successive processes with material flows in what is called the process chart. Each process represents a stage in production and is defined by its input and output. The LCA software tool SimaPro5 (Pré Consultants B.V.) can be used for the evaluation of different products and is also applied in waste management. SimaPro provides different impact assessment methods including the Eco-indicator 99.16 Data have been collected for the most common materials and processes and Eco-indicator 99 numbers, that express the total environmental load, were calculated from them. Standard Ecoindicator 99 values are available for the production of materials (based on 1 kg material), production processes (expressed in square meters or kg), transport (unit is the transport of 1 ton of goods over 1 km), energy (based on 1 MJ energy), and waste processing and recycling (based on 1 kg product).13

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EXAMPLES OF LCA The analysis of a coffee machine and the study of different scenarios for waste treatment of paper and cardboard are used

Figure 4. Eco-indicator of 0.1 kg (A) virgin aluminum, (B) 100% recycled aluminum.

to illustrate the LCA methodology (definition of the functional unit, process chart, inventory analysis, classification, characterization, normalization, weighting, interpretation) with SimaPro5. LCA of a Coffee Machine

The product analyzed is a coffee machine for domestic use. The purpose of the calculation is to obtain an overall impression of the product’s major environmentally damaging processes; thus, only main processes are included. This information can be used to identify environmental hot spots (processes that have a large impact on the environment) and to establish priorities in the search for more environmentally friendly design alternatives. The functional unit is defined as “all the products and processes needed, over a period of 5 years (the life time of the coffee machine), for the provision of 5 cups of coffee twice a day and keeping it hot for half an hour after brewing”. The number of 887



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Figure 5. A simplified process chart for the life cycle of paper.

materials studied, the region in question, the technology used, and so forth.22 There is considerable debate on the relative environmental advantages and disadvantages of recycling versus incineration with energy recovery of paper and cardboard. The vast majority of the LCA studies on the recycling of paper and cardboard indicate that recycling of waste paper and cardboard has a lower environmental impact compared to landfilling and incineration.3,22 The environmental benefit of recycling is less pronounced when incineration with energy recovery is considered. Paper and cardboard have a relatively high heating value, similar to wood, and this energy (13−15 MJ/kg) can be released and utilized via incineration. In many incineration plants, this energy is transformed into electricity and supplied to the grid or supplied directly as heat via district heating. The goal of the LCA is to compare the environmental impact of recycling and incineration with energy recovery of paper and cardboard. The functional unit of the product system is defined as “1 kg paper or 1 kg cardboard waste entering the waste management system”. Figure 5 shows the stages in the life cycle of paper. Paper is essentially a sheet of fibers with a number of added chemicals that affect the properties and quality of the sheet. The main raw materials used for the production of paper are pulp processed from wood and deinked pulp processed from separately collected newspapers and magazines. The report “Best available techniques in the pulp and paper industry” from the European Commission describes the processes, resources, chemicals, and energy used for the production of paper (and cardboard), the emissions to the atmosphere and water and the generation of solid waste during production. This report reveals valuable information on inputs and outputs of the production process and thus on the different components appearing in the inventory table.23,24 The first phase of the life cycle of paper is forestry. The second phase is pulping where wood for paper production may

Figure 6. Eco-indicator incineration (with energy recovery) of 1 kg of paper.

LCA of Paper and Cardboard

The second case study looks at the LCA of paper and cardboard with particular attention to waste management. In the waste policy of the European Union, waste prevention has been set as the first priority of waste management. Prevention is followed by material recycling, recovery as energy and safe final disposal. It is noteworthy that this priority list is not always the most preferable. It appears that the overall sustainability of waste management solutions may vary depending on the 888



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Figure 7. Avoided electricity for 1 kg of incinerated paper.

be received as debarked logs or as byproduct chips from some other wood working industry like sawmills and plywood mills. Chemical and thermo mechanical pulping techniques can be applied to produce cellulose fiber. The sulfate or kraft process is the dominating chemical pulping process worldwide due to the superior pulp strength properties and its application to all wood species. The main raw materials used are renewable resources (wood and water) and chemicals for cooking (to destroy the lignin) and bleaching. Before the early 1990s, free chlorine was used to bleach the paper, but today chlorine dioxide and ozone are used. The kraft pulp process has a high total energy consumption; however, most of it is produced internally from wood as energy resource. In mechanical pulping, the wood fibers are separated from each other by mechanical energy applied to the wood matrix (logs or chips). The objective is to maintain the main part of the lignin to achieve a high yield with acceptable strength properties and brightness. In mechanical pulping, the wastewater effluents (washing, bleaching) and consumption of electricity for the drives of grinders and refiners are the main items. The production of virgin thermo mechanical pulp has a much lower energy consumption, but this energy is mainly obtained from electricity. Because of these differences, it is important and even necessary to clarify what type of pulp is being investigated. The third phase is the manufacturing of paper, where different additives are used to improve the product properties. This phase is followed by the production of newspapers and magazines and their distribution to the readers. For effective use of collected paper, it is necessary to sort and classify this material into suitable quality grades. The sorted paper is usually compacted by baling machines. The options for waste management of paper are paper recycling (repulping), incineration with or without energy recovery, and landfilling. A complete repulping plant includes a repulper, a mechanical cleaning unit, and an deinking unit. The recycled paper is mixed with water and chemicals in the repulper and is agitated to release the cellulose fibers. A mechanical cleaning unit is used for the removal of coarse contaminants (nonpaper items such as stones, sand, metal, string, glass, plastic foils, paper clips, etc.) from the fibers. In the deinking unit, chemicals are added to release ink particles from the fibers. Ink removal is necessary in plants manufacturing paper grades where brightness is important, for example, for printing and writing paper and

newsprint. After deinking, the pulp is thickened and washed and is ready to be used for the production of paper. The students are asked to analyze the Eco-indicator for the processes chemical pulping (kraft process), thermo mechanical pulping, repulping, landfilling, incineration without energy recovery and incineration with energy recovery listed in the database. They are also asked to describe under which conditions incineration with energy recovery is preferable to recycling. The incineration of 1 kg paper has an Eco-indicator value of 3.9 mPt and the electricity produced from the heat released during incineration is 2.16 MJ. The Eco-indicator value for the traditional production of 2.16 MJ electricity in Europe is 11.7 mPt. (Figures 6 and 7). The total Eco-indicator for the incineration of 1 kg of paper with energy recovery is 3.9 mPt − 11.7 mPt = −7.8 mPt. The eco-indicator for the production of 1 kg of paper out of wood varies between 20 and 90 mPt depending on the desired paper quality, the used technology, the geography, and so forth. The production of 1 kg of paper out of 100% recycled fiber is about 32 mPt. Incineration with energy recovery becomes favorable over recycling when the best available techniques are used for fiber production from wood and bleaching. The same exercise is applicable on cardboard.

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TEACHING EXPERIENCES

Selection of Software and Course Content

A lot of LCA software tools are available on today’s market. It is important that the selected LCA tool is easy to use, well documented with a user guide and software tutorial, and comprises several industrial processes with a complete inventory table (raw materials and emissions) and visualization of the results (classification, characterization, normalization and weighting). SimaPro is the program of choice because it answers these criteria and is also intended for non-LCA experts. Students are able to work with it in less than 1 h. In the assessment, real industrial processes and actual environmental issues have to be dealt with. The choice of the material and process should have a clear effect on the outcome of the LCA. In the first example, the students are asked to compare the environmental effect of virgin aluminum and recycled aluminum. Recycled aluminum now accounts for over half of all U.S.-produced aluminum. In the second example students are asked to analyze the eco-indicator for the processes 889



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(12) Dreyer, L. C.; Niemann, A. L.; Hauschild, M. Int. J. Life Cycle Assess. 2003, 8 (4), 191−200. (13) Goedkoop, M. Eco-indicator 99 Manual for Designers; Ministry of Housing, Spatial Planning and the Environment Communications Directorate: The Hague, The Netherlands, 2000; p 48. (14) Azapagic, A. Chem. Eng. J. 1999, 73, 1−21. (15) Wenzel, H.; Hauschild, M.; Alting, L. Environmental Assessment of Products. Vol. 1: Methodology, Tools and Case Studies in Product Development; Kluwer Academic Publishers Group: Dordrecht, The Netherlands, 2001; p 543. (16) SimaPro; Pré Consultants: Amersfoort, The Netherlands. Available from http://www.pre.nl/simapro (17) Gatti, J. B.; de Castilho Queiroz, G.; Corrêa Garcia, E. E. Int. J. Life Cycle Assess. 2008, 13 (3), 219−225. (18) Industrial Technologies Program Energy Efficiency and Renewable Energy. U.S. Energy Requirements for Aluminum Production. Historical Perspective, Theoretical Limits and Current Practices. U.S. Department of Energy, 2007; p 150. (19) Gaustad, G; Olivetti, E.; Kirchain, R. J. Ind. Ecol. 2010, 14 (2), 286−308. (20) European Integrated Pollution Prevention and Control Bureau. Reference Document on Best Available Techniques in the Non-Ferrous Metals Industries: European Commission: Sevilla, Spain, 2001; p 807. (21) European Integrated Pollution Prevention and Control Bureau. Draft Reference Document on Best Available Techniques for the NonFerrous Metal Industries; European Commission: Sevilla, Spain, 2009; p 900. (22) Dahlbo, H.; Laukka, J.; Myllymaa, T.; Koskela, S.; Tenhunen, J.; Seppälä, J.; Jouttijärvi, T.; Melanen, M. Waste Management Options for Discarded Newspaper in the Helsinki Metropolitan Area; Finnish Environment Institute: Helsinki, Finland, 2005; p 151. (23) European Integrated Pollution Prevention and Control Bureau. Reference Document on Best Available Techniques in the Pulp and Paper Industry; European Commission: Sevilla, Spain, 2001; p 509. (24) European Integrated Pollution Prevention and Control Bureau. Draft Reference Document on Best Available Techniques in the Pulp and Paper Industry; European Commission: Sevilla, Spain, 2010; p 746.

chemical pulping, thermo mechanical pulping, and repulping. These processes are well documented in the literature and are applied worldwide. Course Organization

General aspects of the LCA methodology are presented as a teacher-centered course lecture. The process chart of the life cycle of the coffee machine as well as the one of the paper production are explained. The teaching methodology suitable for these two LCA examples is “cooperative learning”. In this type of classroom environment, students are assigned to threemember teams where they work together without formal role assignments. Each team uses a computer with installed software SimaPro for dealing with both LCAs. The teacher manages the progress of students making sure that all members accomplish the goals. Results are summarized and guided by the teacher. Learning Outcomes

The students get a better insight in the different phases of the LCA methodology through the use of the documented LCA database, embedded in the software, as well as through the use of the calculation tool, that generates the inventory table and the data and graphs for classification, characterization, normalization and weighting. Students learn to explore that the assumptions made on technology (old or new), geography, allocation, and so forth influence the main conclusion of the LCA.

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AUTHOR INFORMATION

Corresponding Author

*E-mail: [email protected].

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REFERENCES

(1) Hauschild, M.; Jeswiet, J.; Alting, L. CIRP Ann. 2005, 54 (2), 1− 21. (2) Rebitzer, G.; Ekvall, T.; Frischknecht, R.; Hunkeler, D.; Norris, G.; Rydberg, T.; Schmidt, W.-P.; Suh, S.; Weidema, B. P.; Pennington, D. W. Environ. Int. 2004, 30, 701−720. (3) Villanueva, A.; Wenzel, H.; Strömberg, K.; Viisimaa, M. Paper and CardboardRecovery or Disposal. Review of Life Cycle Assessment and Cost-Benefit Analysis on the Recovery and Disposal of Paper and Cardboard; European Environment Agency: Copenhagen, Denmark, 2005, p 157. (4) ISO 14040: Environmental ManagementLife Cycle Assessment Principles and Framework; International Standard Organisation: Geneva, Switzerland, 1997. (5) ISO 14041: Environmental ManagementLife Cycle Assessment Goal and Scope Definition and Inventory Analysis; International Standard Organisation: Geneva, Switzerland, 1998. (6) ISO 14042. Environmental ManagementLife Cycle Assessment Life Cycle Impact Assessment; International Standard Organisation: Geneva, Switzerland, 2000. (7) ISO 14043: Environmental ManagementLife Cycle Assessment Life Cycle Interpretation; International Standard Organisation: Geneva, Switzerland, 2000. (8) ISO 14040: Environmental ManagementLife Cycle Assessment Principles and Framework; International Standard Organisation: Geneva, Switzerland, 2006. (9) ISO 14044: Environmental Management - Life Cycle Assessment Requirements and Guidelines; International Standard Organisation: Geneva, Switzerland, 2006. (10) Remmerswaal, H. Milieugerichte Productontwikkeling; Academic Service: Schoonhoven, The Netherlands, 2000; p 252. (11) Pennington, D. W.; Potting, J.; Finnveden, G.; Lindeijer, E.; Jolliet, O.; Rydberg, T.; Rebitzer, G. Environ. Int. 2004, 30, 721−739. 890


Life Cycle Assessment Software for Product and Process

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