## 4 Life-Cycle Assessment
### Brief History of Life-Cycle Assessment  
The beginnings of LCA were in the 1960's and were based on concerns over supplies of raw materials and energy resources. Various studies attempted to model long-term energy and raw materials demand and production levels. An internal study of the raw material and energy requirements of beverage containers at the Coca Cola Company in 1969 was the foundation for LCA in the United States. During the 1970's its popularity increased in the United States and Europe. It was called Resource and Environmental Profile Analysis in the United States and Ecobalance in Europe [28]. The Society of Environmental Toxicology and Chemistry (SETAC) sponsored two LCA workshops in 1992 and a year later SETAC LCA advisory groups produced the \"Bible\" of LCA principles and procedures (Guidelines for Life-Cycle Assessment: A \"Code of Practice\") [28]. Since then numerous governmental agencies, mostly in Europe and the United States, have developed their own guidelines [33]. In the mid 1990's an international set of standards was published by the International Standards Organization (ISO) [34] and today are the most recognized [33]:  
\(\bullet\) ISO 14040 Environmental management, LCA, Principles and framework.  
\(\bullet\) ISO 14041 Environmental management, LCA, Goal definition and inventory analysis.  
\(\bullet\) ISO 14042 Environmental management, LCA, Life-cycle impact assessment.  
\(\bullet\) ISO 14043 Environmental management, LCA, Life-cycle interpretation.  
\(\bullet\) ISO 14044 Environmental management, LCA, Requirements and guidelines.  
Life-cycle assessment is an environmentally-based analytical tool and many early applications were related to wood and paper products sustainability issues. LCA will not capture and measure many of the variables that are important in forest certification standards, so actual forest management sustainability life cycle assessments are not very common. Forest products are well-covered in the literature and were some of the first to be analyzed _via_ LCA. Wood [35, 36] and wood products, like wood building supplies [37], softwood lumber [38], plywood [39], oriented standboard [40], I-joists [41], glue-laminated timber [42], and laminated veneer lumber [43] have fully-developed LCAs in the literature and a review of LCA and the environmental impact of buildings has been published in this journal [30]. Pulp and many types of paper have been analyzed by LCA [36, 44-46].  
Forest products tend to be the focus of consumer involvement in terms of actual purchasing decisions that might favor products with lesser environmental impacts. Few consumers interact with the forest, while most all consumers interact with forest products on a regular basis. LCA was used in the mid-1970's to evaluate competitive building materials. The earliest life cycle inventory on wood products was conducted by the National Research Council, Committee on Renewable Resources for Industrial Materials (CORRIM). The CORRIM report contrasted energy requirements to produce various building construction materials. For example, compared to a wood stud wall, steel studs would require nine times more energy to produce and concrete blocks would require three times more energy [47]. Wood in use was not the only LCA focus; declines in Pacific Northwest timber harvests resulted in use of nonrenewable resources for construction purposes and significant carbon dioxide being added to the atmosphere. Wood was shown to use less energy in the manufacturing process and to produce less carbon dioxide emissions than steel or concrete [48]. LCA has generally been restricted to life cycle inventories for the wood and paper industries; a full LCA would be very complex andwould have to start with timber growing, harvesting, cutting, barking and chipping in the woods and follow through manufacturing, processing, use, and disposal. The manufacturing process has thus been the focus of LCA in these industries [49].