LECTURE NOTES For Environmental Health Science Students Engineering Drawing Wuttet Taffesse, Laikemariam Kassa Haramaya University In collaboration with the Ethiopia Public Health Training Initiative, The Carter Center, the Ethiopia Ministry of Health, and the Ethiopia Ministry of Education 2005
Funded under USAID Cooperative Agreement No. 663-A-00-00-0358-00. Produced in collaboration with the Ethiopia Public Health Training Initiative, The Carter Center, the Ethiopia Ministry of Health, and the Ethiopia Ministry of Education. Important Guidelines for Printing and Photocopying Limited permission is granted free of charge to print or photocopy all pages of this publication for educational, not-for-profit use by health care workers, students or faculty. All copies must retain all author credits and copyright notices included in the original document. Under no circumstances is it permissible to sell or distribute on a commercial basis, or to claim authorship of, copies of material reproduced from this publication. ©2005 by Wuttet Taffesse, Laikemariam Kassa All rights reserved. Except as expressly provided above, no part of this publication may be reproduced or transmitted in any form or by any means, electronic or mechanical, including photocopying, recording, or by any information storage and retrieval system, without written permission of the author or authors. This material is intended for educational use only by practicing health care workers or students and faculty in a health care field.
PREFACE The problem faced today in the learning and teaching of engineering drawing for Environmental Health Sciences students in universities, colleges, health institutions, training of health center emanates primarily from the unavailability of text books that focus on the needs and scope of Ethiopian environmental students. This lecture note has been prepared with the primary aim of alleviating the problems encountered in the teaching of Engineering Drawing course and in minimizing discrepancies prevailing among the different teaching and training health institutions. It can also be used as a reference material for professional sanitarians. The graphics of engineering design and construction may very well be the most important course of all studies for an engineering or technical career. The indisputable reason why graphics or drawing is so extremely important is that it is the language of the designer, technician, sanitarian, and engineer, used to communicate designs and construction details to others. The language of graphics is written in the form of drawings that represent the shape, size, and specifications of physical objects. The language is read by interpreting drawings so that physical objects can be constructed exactly as originally conceived by the designer. i
This lecture note is devoted to provide general aspects of graphic communication orthographic projections, like maps geometric etc construction, particularly for environmental sanitation works such as dry pit latrine construction, drainage or sewerage construction etc. Each chapter begins by specifying learning objectives. The text and the self-explanatory drawings are much helpful to understand the subject even for the beginners. More over, other subsidiary topics like sectioning, projection of points and lines are added to enable students acquire concrete knowledge and skill for their professional career. Finally, it contains a glossary, which summarizes important terminologies used in the text. For further reading, students are encouraged to refer books which are listed in the bibliography section. ii