I. INTRODUCTION
This course provides the training of visual inspectors to a level whereby they can teach the SDI/TDI Visual Inspection program to others.

II. COURSE OBJECTIVES
To re-emphasize to inspector instructor candidates the proper handling, filling, and inspection techniques including the identification of the various defective conditions which can lead to cylinder rejection or condemnation. A great deal more emphasis is placed on the knowledge base of the instructor candidate than is normally required of a cylinder inspector.

III. QUALIFICATIONS OF GRADUATES
A. Upon successful completion of this course graduates may teach others to visually inspect high-pressure scuba cylinders for defective conditions which could cause a cylinder failure.

IV. WHO MAY TEACH
This course may be taught by any active SDI/TDI Visual Inspector Instructor Trainer.

V. INSTRUCTOR - INSTRUCTOR TRAINER RATIO
A. No more than 5 instructor candidates per demonstration setup (tools and tanks for the practical)
B. No more than 25 candidates per active SDI/TDI Instructor Trainer

VI. INSTRUCTOR CANDIDATE PREREQUISITES
A. Minimum age of 21.
B. Be affiliated with an organization that has a high pressure air compressor and fill station
C. Be a qualified cylinder inspector by a nationally recognized agency.
D. Can prove that he/she has inspected a minimum of 50 high-pressure cylinders.
E. Has been a Visual Inspector for a minimum of 6 months.

VII. REQUIRED COURSE MINIMUMS
Classroom lecture and demonstrations hours - 5

VIII. REQUIRED MATERIALS - CANDIDATES
Each instructor candidate is required to have a copy of the following:
A. SDI/TDI Visual Inspection Procedures Student Manual
B. SDI/TDI Visual Inspection Procedures Instructor Manual

IX. REQUIRED EQUIPMENT
The following equipment is the minimum required per inspection group while performing the visual inspection procedure. The instructor trainer may provide the required equipment.
A. A right angle mirror (dental mirror) with a magnification of 2X and having a diameter small enough to enter the tank neck.
B. Inspection light of sufficient size and intensity to illuminate the mirror and threads being inspected.
C. A light wand or other light source to illuminate the interior surfaces of the cylinder being inspected.
D. A right angle 1X power mirror and light source to enable the inspection of the interior crown area of the cylinder being inspected.
E. A straight and right angle pick and some gauging method to estimate the depth of any pitting noted on the cylinder walls.

X. REQUIRED SUBJECT AREAS
The following topics must be covered during this course. The SDI/TDI Visual Inspection Procedures Student Manual and the SDI/TDI Visual Inspector Instructor manual are mandatory for use during this course, but instructors may use any other text or materials that they feel help present these topics.
A. Purpose
B. Legal requirements, standards of the community
C. Safe handling of cylinders
D. Fill station operator rules and recommendations
1. Identification of the various tank markings
2. Legal / illegal filling requirements
3. Filling procedures
4. Use of and interpretation of EOI stickers
E. Tools and their uses
1. Use of eddy current technology in assisting the detection of thread cracks in 6351-T6 aluminum cylinders
F. Visual inspection indications
1. Proper identification of the various defect conditions
G. Criteria for rejection and condemnation of a cylinder
1. Define the criteria for cylinder rejection
2. Define the criteria for condemning a cylinder
3. Cover when to mark a cylinder “With notation”
H. Other services
1. Valve inspection and cleaning
2. The basis for cylinder cleaning
I. Visual Inspection Procedure
1. Step by step walkthrough of the inspection process

XI. REQUIRED SKILLS
The student is required to display a degree of competency in the identification of various defect conditions presented to him by the instructor using actual cylinders with known defective conditions.
A. Inspect three cylinders with at least one having a defective condition

XII. GRADUATION REQUIREMENTS
In order to complete the course, students must:
A. Satisfactorily complete the SDI/TDI Visual Inspection written examination.
B. Satisfactorily complete the SDI/TDI Visual Inspection Instructor written examination.
C. Demonstrate the ability to identify those conditions in a cylinder that would reject or condemn it.

XIII. SUPPORT MATERIALS
A. Instructor Registration
B. SDI/TDI Visual Inspection Procedures Power Point Presentation
C. CGA publication C6-1993
D. CGA publication C6.1-1995
E. CFR 49 parts 171 - 179