Pre-Inspection Surface Preparation Checklist for NDT

Use this checklist before removing paint, rust, oxide, scale, or residue from an area scheduled for nondestructive testing. It is designed to coordinate the owner, maintenance team, surface-preparation contractor, and qualified NDT representative before work begins.

1. Confirm the Inspection Authority

• □ Name the owner, engineer, inspection company, or other party controlling the examination.
• □ Identify the NDT Level II, Level III, or other authorized representative who can answer preparation questions.
• □ Obtain the applicable drawing, work order, code reference, procedure, and revision.
• □ Record who may approve the test area and who has final authority to accept the prepared surface.
• □ Confirm that the preparation contractor is not being asked to interpret indications or certify the examination.

2. Define the Examination

• □ Select the method: PT/LPI, MT/MPI, UT, ET, VT, or another method.
• □ Identify the exact component, weld, joint, heat-affected zone, scan path, or inspection window.
• □ Mark the required boundary and the margin around the examination area.
• □ Record whether the inspection targets surface, near-surface, or internal discontinuities.
• □ Confirm whether more than one NDT method will be used and in what sequence.
• □ Record any lighting, access, temperature, dryness, or surface-roughness limits in the procedure.

3. Document the Asset and Existing Surface

• □ Identify the substrate and alloy when known.
• □ Confirm whether material intended for MT is ferromagnetic.
• □ Record coating type, number of layers, approximate thickness if known, and application history.
• □ Photograph corrosion, scale, soot, process residue, grease, oil, weld spatter, previous penetrant, magnetic-particle carrier, or contrast coating.
• □ Identify possible lead, chromium, cadmium, asbestos, or other hazardous constituents from records or testing.
• □ Note cracks, sharp edges, thin sections, machined surfaces, identification marks, and geometry that must be preserved.
• □ Record prior repairs, heat treatment, grinding, blasting, chemical cleaning, or earlier NDT work when known.

4. Apply the Method-Specific Questions

PT / LPI

• □ What must be removed so penetrant can reach surface-breaking openings?
• □ Is the material solid and nonporous under the selected PT procedure?
• □ What cleaner, rinse, drying time, and surface temperature does the procedure require?
• □ Could oil, grease, moisture, old penetrant, carrier, or smeared material remain inside discontinuities?
• □ Does the inspector need PT completed before another method deposits material on the surface?

MT / MPI

• □ Has the inspector confirmed that the material is ferromagnetic?
• □ Is any existing coating allowed to remain, and if so, what limit applies under the procedure?
• □ Must rust, scale, grease, weld spatter, or loose debris be removed for particle mobility, contrast, yoke placement, or sensitivity?
• □ Will contrast coating be applied after preparation?
• □ Who handles magnetization, field verification, demagnetization, and post-inspection cleaning?

UT

• □ What probe footprint and scan path must contact the part?
• □ Must coating or corrosion be removed, or can the selected technique inspect through the existing condition?
• □ What surface smoothness and couplant compatibility are required?
• □ Are temperature, curvature, access, or calibration locations defined?

ET and VT

• □ For ET, does the selected technique require bare conductive material, or can it work through the coating?
• □ For VT, what coating, residue, corrosion product, or obstruction must be removed to expose the required features?
• □ What lighting, magnification, borescope, camera, or dimensional access must remain available?

5. Compare Preparation Methods

• □ Evaluate laser cleaning, power tools, abrasive blasting, chemical cleaning, or a combined sequence against the required outcome.
• □ Separate contaminant removal from any profile requirement.
• □ Identify added media, residue, scratch, smearing, heat, dust, noise, spark, containment, and cleanup concerns for each method.
• □ Confirm that no blast-cleaning or coating-preparation standard is being assigned to a different process without a valid specification basis.
• □ Select the smallest representative test area that includes the real substrate and contaminant combination.

6. Plan the Work Area and Safety Controls

• □ Record whether the work is indoors, outdoors, occupied, operating, elevated, confined, or near sensitive equipment.
• □ Identify nearby combustible material, reflective surfaces, openings, windows, traffic, and uncontrolled access routes.
• □ Define isolation, lockout/tagout, ventilation, extraction, fire-watch, access-control, and housekeeping responsibilities as applicable.
• □ For Class 4 laser work, establish the controlled area, trained personnel, wavelength-appropriate protective eyewear, beam controls, extraction, and emergency procedures.
• □ Plan characterization, collection, labeling, storage, transport, and disposal of removed material and process waste where required.
• □ Confirm permits, owner rules, union requirements, hot-work classification, or site-specific approvals before mobilization.

7. Approve the Test Area

• □ Photograph and identify the test location before work.
• □ Record the preparation method and agreed target condition.
• □ Stop and review any unexpected substrate response, residue, coating behavior, or access limitation.
• □ Complete the procedure-required final cleaning and drying.
• □ Have the authorized NDT representative inspect and approve or reject the test area.
• □ Record any changes required before production preparation begins.

8. Define the Handoff Record

• □ Before-and-after photographs with identifiable locations.
• □ Marked drawings, inspection windows, or component identifiers.
• □ Date, shift, access condition, and work area released.
• □ Preparation method and any project-specific work-completion notes agreed in advance.
• □ Outstanding final-cleaning steps assigned to the appropriate party.
• □ Inspector acknowledgment that the surface was received for examination.
• □ Clear distinction between surface-preparation records and the separate NDT report.

Primary Sources

• ASNT — NDT Methods
• ASNT — Liquid Penetrant Testing
• ASNT — Magnetic Particle Testing
• ASNT — Ultrasonic Testing
• ASNT — Electromagnetic Testing
• ASNT — Visual Testing
• OSHA Technical Manual — Laser Hazards and Controls