GDT300 - Geometric Dimensioning & Tolerancing (GDT)

Outline info
Last revision date 2017-05-29 00:39:46.88
Last review date 2017-07-17 00:16:21.049

Subject Title
Geometric Dimensioning & Tolerancing (GDT)

Subject Description
This subject introduces students to geometric dimensioning and tolerancing (GD&T), a design specific manufacturing and inspection language for effective technical communication. Students learn the symbols, rules, definitions and terminologies of GDT as outlined in the current standard ASME Y14.5M-1994. This subject includes hands-on practice in the lab.

Credit Status
One credit toward the Manufacturing Quality Inspection Certificate Program

Learning Outcomes
Upon successful completion of this subject the student will be able to:

1. Define geometric dimensioning and tolerancing (GDT) and commonly used GDT terminology

2. Apply the rules of the ASME standard Y14.5M-1994

3. Use standard GDT symbols appropriately

4. Recognize various sources of standards related to GDT

5. Use GDT to create and inspect parts according to CSA/ANSI standards

6. Use GDT to communicate drawings and designs

Cheating and Plagiarism
Each student should be aware of the College's policy regarding Cheating and Plagiarism. Seneca's Academic Policy will be strictly enforced.

To support academic honesty at Seneca College, all work submitted by students may be reviewed for authenticity and originality, utilizing software tools and third party services. Please visit the Academic Honesty site on for further information regarding cheating and plagiarism policies and procedures.

All students and employees have the right to study and work in an environment that is free from discrimination and/or harassment. Language or activities that defeat this objective violate the College Policy on Discrimination/Harassment and shall not be tolerated. Information and assistance are available from the Student Conduct Office at

Accommodation for Students with Disabilities
The College will provide reasonable accommodation to students with disabilities in order to promote academic success. If you require accommodation, contact the Counselling and Disabilities Services Office at ext. 22900 to initiate the process for documenting, assessing and implementing your individual accommodation needs.

Students should have a minimum Ontario Secondary School Diploma,or mature student status and industrial or mechanical design  and drafting experience. Instruction is not provided in basic drafting or the principles of mechanical design.

Students are reminded that they are responsible for assessing their eligibility for the subject.

Topic Outline

  • Engineering Drawing and Tolerancing
  • Introduction to Geometric Tolerancing Symbols and Terms
  • Rules and Concepts of GDT
  • Form Controls
  • Datums (Planer)
  • Datums (Axis and Centerplane)
  • Ordination Control
  • Tolerance of Position

Mode of Instruction
Lectures, labs, presentations, demonstrations, videos/movies.

Prescribed Texts
Fundamentals of Geometric Dimensioning and Tolerancing, 3rd edition, Alex Krulikowski, Nelson Education Inc. ISBN: 9781111129828

Reference Material

Required Supplies

Promotion Policy

Grading Policy
A+ 90%  to  100%
A 80%  to  89%
B+ 75%  to  79%
B 70%  to  74%
C+ 65%  to  69%
C 60%  to  64%
D+ 55%  to  59%
D 50%  to  54%
F 0%    to  49% (Not a Pass)
EXC Excellent
SAT Satisfactory
UNSAT Unsatisfactory

For further information, see a copy of the Academic Policy, available online ( or at Seneca's Registrar's Offices.

Modes of Evaluation

  • Assignments are due at the beginning of the class on which they are due.
  • A late penalty of 10% per day is assessed for late assignments, including those not handed in at the beginning of class when due.
  • Material will not be accepted after one week following the due date and/or when the marked material is returned to students, whichever comes first.
  • Assignments are to be prepared by computer.

Absenteeism and Exams
  • Students should be aware that absenteeism almost guarantees an inability to achieve satisfactory grades.
  • Students who are absent for an examination due to an emergency (e.g., motor vehicle accident, hospitalization or death in the family) may provide official documentation within five days of the missed exam and be provided a deferred exam at a later date.  Official documentation includes a death notice or an original doctor’s certificate identifying the date, length of time expected absence and the specific reason for the absence.  Examinations missed without official documentation and approval result in a grade of zero.
  • There are no deferred options for missed tests.  The value of missed tests, at the discretion of the Faculty, will be added to other evaluation components

English Proficiency
  • All written work should demonstrate the following characteristics for clarity and conciseness:
-writing is consistent with the rules of English grammar
-spelling and punctuation are correct
-sentences are structured correctly
-main ideas are supported with specific, relevant examples and reasons
-work flows logically through supporting statements/paragraphs
-work is arranged in correct format (e.g., as a report, essay)
-up to 10% of the final grade may be deducted on all work if the above English competencies are not met.

Format for Assignments
  • Students must use the standard, APA style for quoting sources.   Help is available at:

Laboratory Attendance
The laboratory component is essential and therefore it is strongly recommended  that you attend all labs.  Any missed labs must be supported with a legal document with three days of the lab.  Any student who fails to attend 2 scheduled laboratory classes for a 7 week subject and more than 3 laboratory classes for a 14 week subject will not pass the subject.    

Laboratory Safety
Students are required to review and understand the safety procedures and guidelines outlined on the first class and sign the sheet to this effect before beginning work in the laboratory.  Students must also wear a lab coat and safety glasses when conducting experiments.
A student who arrives without the proper safety equipment will not be permitted to participant in the lab but will be asked to leave the class.  The student will receive no grade for the lab missed.

Grading is based on the following marking scheme:

Term Tests (3 at 20% each) 60%
Assignment 10%
Final Exam 30%
Total 100%

**Please retain this document for future educational / employment use.

Other Evaluation Considerations
The student is expected to comply with the Safety Rules for working in the laboratory, sign the safety contract, and WILL NOT UNDER ANY CIRCUMSTANCES WEAR CONTACT LENSES in the laboratory.  The student will know where all safety equipment is located in the laboratory and will be familiar with WHMIS concepts and signage.


Approved by: Denis Gravelle