This book has come as a contribution in establishing a standalone reference in the field of air engineering and science, as such a book is desperately needed in undergraduate teaching, postgraduate research, science and scientific research and engineering projects, solving air pollution problems, and much more. The book aims to help in planning, designing, proofing and operating air cleaning plantations and in solving air pollution problems. The book proved of value to engineers, medical personnel, public health operators, city planners, agricultural engineers and general researchers.