The 12 Principles of Green Engineering
[First published in Paul T. Anastas and J.B. Zimmerman, "Design through the Twelve Principles of
Green Engineering", Environmental Science & Technology Vol. 37, No. 5 (March 1, 2003), pp. 95A-101A.]
Principle 1: Designers need to strive to ensure that all material and energy inputs and outputs are as
inherently non hazardous as possible.
Principle 2: It is better to prevent waste than to treat or clean up waste after it is formed.
Principle 3: Separation and purification operations should be designed to minimize energy consumption and
Principle 4: Products, processes, and systems should be designed to maximize mass, energy, space, and time
Principle 5: Products, processes, and systems should be "output pulled" rather than "input
pushed" through the use of energy and materials.
Principle 6: Embedded entropy and complexity must be viewed as an investment when making design choices on
recycle, reuse, or beneficial disposition.
Principle 7: Targeted durability, not immortality, should be a design goal.
Principle 8: Design for unnecessary capacity or capability (e.g., "one size fits all") solutions
should be considered a design flaw.
Principle 9: Material diversity in multicomponent products should be minimized to promote disassembly and
Principle 10: Design of products, processes, and systems must include integration and interconnectivity
with available energy and materials flows.
Principle 11: Products, processes, and systems should be designed for performance in a commercial "afterlife".
Principle 12: Material and energy inputs should be renewable rather than depleting.
The 12 Principles of Green Chemistry
[First published in Martyn Poliakoff, J. Michael Fitzpatrick, Trevor R. Farren, and Paul T. Anastas, "Green
Chemistry: Science and Politics of Change," Science Vol. 297 (August 2, 2002), pp. 807-810.]
It is better to prevent waste than to treat or clean up waste after it is formed.
Synthetic methods should be designed to maximize the incorporation of all materials used in the process
into the final product.
Wherever practicable, synthetic methodologies should be designed to use and generate substances that
possess little or no toxicity to human health and the environment.
Chemical products should be designed to preserve efficacy of function while reducing toxicity.
The use of auxiliary substances (e.g., solvents, separation agents, and so forth) should be made
unnecessary wherever possible and innocuous when used.
Energy requirements should be recognized for their environmental and economic impacts and should be
minimized. Synthetic methods should be conducted at ambient temperature and pressure.
A raw material or feedstock should be renewable rather than depleting wherever technically and
Unnecessary derivatization (blocking group, protection/deprotection, temporary modification of physical/chemical
processes) should be avoided whenever possible.
Catalytic reagents (as selective as possible) are superior to stoichiometric reagents.
Chemical products should be designed so that at the end of their function they do not persist in the
environment and break down into innocuous degradation products.
Analytical methodologies need to be developed further to allow for real-time in-process monitoring and
control before the formation of hazardous substances.
Substances and the form of a substance used in a chemical process should be chosen so as to minimize
the potential for chemical accidents, including releases, explosions, and fires.
[From the Los Angeles Times, January 18, 2008 :-]