ASNT NDT III LT study plan
ASNT NDT III LT · Give each week a clear focus.
8 weeks · About 6 hours per week
Leak Testing (LT) Method Fundamentals and Techniques
Define leak testing principles, leak rate units, and the distinction between leak and permeation/outgassing
Differentiate tracer-gas, pressure-change, bubble-emission, and mass-spectrometer techniques by sensitivity range
Explain the operating principle of helium mass spectrometer leak detection including vacuum vs. sniffing modes
Convert between leak rate units (atm-cc/s, mbar-L/s, Pa-m3/s) and order-of-magnitude sensitivities
Your checkpoint
One-page comparison matrix of LT techniques with sensitivity ranges and unit conversions worked out
Leak Testing (LT) Method Fundamentals and Techniques
Select an appropriate LT technique for a given component, sensitivity requirement, and production environment
Describe calibration and reference-leak practices for at least two techniques
Identify common false indications and sources of error (virtual leaks, background helium, temperature effects)
Outline safety controls for vacuum, pressure, and tracer-gas hazards
Your checkpoint
Written technique-selection rationale for three hypothetical parts with sensitivity targets and justification
Leak Testing Method Qualification, Administration, and Procedure Development
Draft a leak test procedure to a recognized format including scope, references, personnel, and acceptance criteria
Write step-by-step test instructions with equipment setup, calibration steps, and data-recording requirements
Establish acceptance/rejection criteria tied to a specified leak rate and test sensitivity
Define documentation, traceability, and reporting fields required for a compliant procedure
Your checkpoint
Complete draft LT procedure document (3-5 pages) with all required sections
Leak Testing Method Qualification, Administration, and Procedure Development
Explain method qualification/validation concepts including sensitivity, repeatability, and reproducibility
Design a demonstration-of-capability test for a chosen LT technique
Evaluate procedure effectiveness against a known reference standard or calibrated leak
Identify revision-control and re-qualification triggers
Your checkpoint
Written qualification plan with pass/fail criteria for a selected LT technique
General NDT Knowledge and Basic Physics
Apply gas laws (ideal gas, Boyle's, Dalton's) to leak rate and pressure-change calculations
Explain viscosity, molecular flow, and conductance effects on leak detection sensitivity
Describe basic vacuum system components and their role in LT
Perform order-of-magnitude calculations relating pressure change, volume, and time to leak rate
Your checkpoint
Worked problem set of ten quantitative leak-rate and gas-law calculations with solutions
General NDT Knowledge and Basic Physics
Summarize general NDT method families and where LT fits relative to other methods
Explain basic transducer, sensor, and signal-conditioning principles used in LT instruments
Describe material and surface effects (adsorption, permeation) that influence LT results
Interpret instrument readouts and distinguish signal from noise
Your checkpoint
Annotated summary sheet of general NDT physics and instrument principles relevant to LT
Certification Program Administration and Standards (SNT-TC-1A, CP-189)
Compare SNT-TC-1A and CP-189 requirements for written practice, training, experience, and examination
Map the Level I/II/III duties and responsibilities to LT-specific tasks
Outline the certification and recertification cycle including examination structure and grading
Identify employer responsibilities for maintaining certification records and administering the program
Your checkpoint
Side-by-side SNT-TC-1A vs. CP-189 comparison table with LT-specific certification requirements
Leak Testing (LT) Method Fundamentals and Techniques & Leak Testing Method Qualification, Administration, and Procedure Development & General NDT Knowledge and Basic Physics & Certification Program Administration and Standards (SNT-TC-1A, CP-189)
Review all four domains using a structured question set and log weak areas
Re-derive key calculations and unit conversions from memory
Re-explain the technique-selection and procedure-writing logic without notes
Complete a timed practice assessment and analyze errors by domain
Your checkpoint
Timed practice exam score report with a written remediation list for remaining weak areas
Milestones
Week 2: Can correctly select an LT technique and justify sensitivity for an unseen part in under 10 minutes
Week 4: Has a complete drafted procedure and qualification plan that a peer can follow without clarification
Week 6: Scores 80% or better on a self-administered quantitative gas-law and physics problem set
Week 8: Achieves 80% or better on a full-length timed practice assessment across all four domains