Yale University
225 Prospect Street
New Haven, CT 06520
phone: 203.432.5215
greenchemistry@yale.edu

Overview of Green Chemistry and Green Engineering

In chemistry, safety is usually thought of as an issue of chemical exposure; risk is managed through specialized training of personnel and use of protective equipment.  There are problems with this approach from an economic standpoint and also in terms of human health and the environment-- when protections fail or the connections between exposures and harmful effects are not well understood, risk may be unintentionally maximized.  Green chemistry offers a different approach.  When hazard is considered as an inherent chemical property just as malleable to chemists as color, odor, or melting point, it becomes possible to design products  and processes for reduced hazard.  In other words, hazard is seen as a design flaw.  When hazard is minimized, exposure levels become irrelevant and risk is permanently lower.  Green chemists avoid risk-risk tradeoffs by adhering to a set of principles that encompass the entire lifecycle of a chemical.

Green engineering is also based on reduction of inherent waste and hazards in all stages of the lifecycle of a material, product, process, or system.  Green engineering moves beyond baseline engineering quality and safety specifications to consider environmental, economic, and social factors.