NON DESTRUCTIVE TESTING EVALUATION Auditor NDT Training The purpose of this training is to give the auditor a familiarity of the quality control and quality assurance systems associated with Nondestructive testing. Agenda: Training and Certification. Audit/Evaluation & Surveillance. Liquid Penetrant Inspection. Magnetic Particle Inspection. Radiography Inspection. Ultrasonic Inspection. Eddy Current Inspection Overview: 1) Documentation- written procedures, processes specifications and/or methods used by the vendor in performance and controls of NDT activities. 2) Organization- relationship of NDT organization to management. 3) Environment- the general physical condition of the facility, e.g.,housekeeping, storage, safety, consumable management, equipment. 4) Calibration- process by which an item is checked to a standard. 5) Training- methods used and records maintained to train and retrain NDT personnel

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AUDITOR NDT TRAINING
 The purpose of this training is to give the
auditor a familiarity of the quality control
and quality assurance systems associated
with Nondestructive testing.

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Introduction
 The reference material used in this
presentation is SNT-TC-1A, ASTM
Standards 2000 edition, Nondestructive
inspection evaluation checklist (from FAA
sight).
 From this presentation you should be able
to be able to understand and evaluate an
NDT facilities quality systems.

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Agenda
 Training and Certification.
 Audit/Evaluation & Surveillance.
 Liquid Penetrant Inspection.
 Magnetic Particle Inspection.
 Radiography Inspection.
 Ultrasonic Inspection.
 Eddy Current Inspection.

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Overview
 It is recognized that the effectiveness of
nondestructive testing applications depends upon
the capabilities of the personnel who are
responsible for and perform it.
 As the auditor you will be required to evaluate
NDT personnel and facilities to make a
determination of compliance in accordance with
the vendors manual, and required specifications.
 The five elements that can be used to evaluate
any NDT organization from manufacturing to
maintenance.

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Overview
1) Documentation- written procedures, processes
specifications and/or methods used by the vendor
in performance and controls of NDT activities.
2) Organization- relationship of NDT
organization to management.
3) Environment- the general physical condition
of the facility, e.g.,housekeeping, storage, safety,
consumable management, equipment.
4) Calibration- process by which an item is
checked to a standard.
5) Training- methods used and records
maintained to train and retrain NDT personnel

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Training and Certification
 The requirements for training,
qualification, and certification in each
NDT method should be part of the vendors
manual or written practice.
 Some recommended practices are ASN-
TC-1A, ANSI/ASNTCP89 NAS 410
(previously Mil Std 410E), ATA105, ISO
9712.

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Training and certification
 Three basic Levels of qualification.
1) Level I- An NDT Level I individual
should be qualified to properly perform
specific calibrations, specific NDT, and
specific evaluations for acceptance or
rejection determinations according to
written instructions and to record
results.The NDT Level I should receive the
necessary instruction or supervision from a
certified Level II or III individual.

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Training and certification
2) Level II- An NDT Level II individual should
be qualified to set up and calibrate equipment
and to interpret and evaluate results with respect
to applicable codes, standards and
specifications.The Level II should be thoroughly
familiar with the scope and limitations for
methods for which qualified and should exercise
assigned responsibilities for OJT training and
guidance of trainees and Level I personnel.

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Training and certification
3) Level III- An NDT Level III individual should
be capable of developing, qualifying, and
approving procedures, establishing and
approving techniques, interpreting codes,
standards, and specifications and procedures; and
designating the particular NDT methods,
techniques, and procedures used. The NDT Level
III should be responsible for the NDT operations
for which qualified and assigned and should be
capable of interpreting and evaluating results in
terms of existing codes, standards and
specifications.

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Training and certification
Level III continued- The NDT Level III should
have sufficient practical background in
applicable materials, fabrication and product
technology to establish techniques and to assist
in establishing acceptance criteria when none are
otherwise available. The NDT Level III should
have general familiarity with other appropriate
NDT methods, as demonstrated by an ASNT
Level III examination or other means. The NDT
Level III , in the methods in which certified,
should be capable of training and examining
NDT Level I and II personnel for certification in
those methods

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Training and certification
 Some procedure also may call out for a trainee, a
trainee is not authorized to accomplish, interpret
or report any inspection requirements.
 Some procedures may also call out for an NDT
instructor an instructor is usually a Level II
working under direction of the companies Level
III.
 These Levels may also be subdivided into
approval to comply with specific procedures such
as conductivity, ultrasonic thickness
measurement( should be in the vendors written
practice)

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Training and certification
 The required amount of training required to
qualify and certify the NDT inspector should be
part of the vendors written practice.
 The requirements of each recommended practice
vary on the amount of formal training and
experience.
 Personnel should complete sufficient organized
training to become thoroughly familiar with
principles and practices of the specified NDT
method.

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Examination
 May be accomplished by an outside
agency, but does not alleviate the employer
of responsibility.
 For Level I and II a general, specific, and
practical test is required.(ASNT)
 For Level III a basic, method, and specific
test is required.(ASNT)

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Examination
 The Level III shall be responsible for the
administration and grading of examinations for
Level I Level II or other Level III personnel.
 For Level I or II personnel the composite grade
should be determined by averaging the results of
the general, specific and practical exam.(ASNT)
Note-ISO 9712 has a general and specific exam and
each exam will have a written and a practical part
 For Level III personnel the composite grade
should be determined by averaging the results of
the basic (required only once), method, and
specific exams.(ASNT)

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Examination
 Minimum passing grade should consist of no
individual test grade below 70% and the
composite grade should be no less than 80%
(ASNT).
 When an examination is administered and graded
for an employer by an outside agency and the
outside agency issues a pass or fail only, on a
certified report the employer may accept the pass
grade as a 80% for that particular examination
(ASNT).

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Examination
Also an eye exam should be accomplished
annually for near vision acuity and every 3
years for color contrast Differentiation.
Re-certification for Level I and II should be
every 3years, Level III every 5
years.(ASNT)

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Training and certification
 The employer’s certification shall be deemed
revoked when employment is terminated.
 A Level I, II or III certification may be re-
instated to the former NDT Level by a new
employer based on examination, provided all the
all these conditions have been met.
1) employee has proof of prior certification.
2) The employee was working in the capacity to
which certified within 6 months of termination.
3)The employee is being re-certified within
within 6 months of termination.

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Training and certification
4) Prior to being examined for certification,
employees not meeting the above
requirements should receive additional
training as deemed appropriate by the
Level III.(ASNT)

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Training and certification
 A Level I, II, or III whose certification has
been terminated may be re-instated to the
former NDT Level, without a new
examination, provided all the following
conditions have been met.
1) The employer has maintained the personnel
certification records.
2) The employees certification did not expire
during termination.
3) The employee is being re-instated within 6
months of termination (ASNT)

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Audit / Evaluation and
Surveillance
 Documentation
1) Does the facility have a manual to
include an organizational chart?
2) Does the manual contain or refer to the
appropriate specifications, are they
current , and available?
3) Are there provisions in the manual for
internal review/evaluation and are the
appropriate records maintained?

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Audit / Evaluation and
Surveillance
5) Are there procedures in place to revise the
manual?
6) Are there procedures in place for retention of
records?
7) Does the manual contain procedures that address
nonconformities?
8) Are the manuals and procedures available to and
used by qualified personnel?
9) Does the manual contain controls for
subcontracts for NDI services?
10) Does the manual contain controls for
management of NDI products, materials, and
consumables?

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Audit/Evaluation and
Surveillance
11) Is there a separate NDI organization in the
facility?
12) Does the NDI manager or equivalent have
direct line authority to the NDI qualified
personnel?
13) Are the NDI requirements provided to the NDI
inspection personnel by use of written practice?
14) Does the NDI manager, or equivalent, review
the quality assurance system to monitor
compliance to the FAA approved data?
15) Are proper shift change procedures in place?

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Audit/Evaluation and
Surveillance
Environment
1) Is the size of the work area sufficient to perform
the NDI inspections?
2) Is there adequate work area for storage and
separation of NDI materials?
3) Is there a method for controlling and segregating
nonconforming NDI equipment and materials?
4) Are appropriate manuals, procedures, and other
documentation available for use by qualified
personnel?

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Audit/Evaluation and
Surveillance
 Environment (continued)
5) Are adequate parts handling systems (cranes,
hoists, lifts etc…) available?
6) Do routing documents specify the operation
needed and in what sequence?
7) Is adequate protection provided to parts during
handling and routing?
8) Is metal to metal contact of finished surfaces
prevented during handling?
9) Are obsolete documents removed from
inspection areas

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Audit / Evaluation and
Surveillance
 Calibration
1) Is there a procedure for calibrating
inspection devices to certified standards?
2) Are there procedures for segregation of
functional and nonfunctional equipment?
3) Are procedures in place to ensure repaired
equipment is recalibrated?
4) Are reference standards properly labeled,
stored and used?
5) Are independent data available for reference
standards, ie., drawings, metrology, etc.?

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Audit / Evaluation and
Surveillance
 Calibration (continued)
6) Are the calibration methods
documented?
7) Do calibration methods include
environment controls, standards to be
used, and accuracy requirements?
8) Are setup verifications performed on all
shifts as appropriate?

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Liquid Penetrant (ASTM E1417)
 2 Basic Types
1) Type I Fluorescent
2) Type II Visible
 4 Methods
1) Method A – Water washable
2) Method B – Post-emulsified, lipophilic
3) Method C – Solvent-removable
4) Method D – Post-emulsified,
hydrophilic

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Liquid Penetrant
 Sensitivity Levels – These levels are for
Type I penetrants only. Type II penetrants
have only a single sensitivity and is not
represented by any level.
1) Sensitivity Level ½ - Very low
2) Sensitivity Level 1 – Low
3) Sensitivity Level 2 – Medium
4) Sensitivity Level 3 – High
5) Sensitivity Level 4 – Ultrahigh

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Liquid Penetrant
 Developers shall be the following forms
1) Form a – Dry powder
2) Form b – Water-soluble
3) Form c – Water-suspendable
4) Form d – Nonaqueous for Type I
fluorescent.
5) Form e – Nonaqueous for Type II
visible dye.
6) Form f – Specific application

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Liquid Penetrant
 Solvent removers shall be of the following
classes
1) Class 1- Halogenated
2) Class 2 –Nonhalogenated
3) Class 3 – Specific application

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Liquid Penetrant
 Quality control and system performance.
1) Penetrant contamination –
Accomplished daily to determine if any of
the following conditions are evident:
precipitates, waxy deposits, white
coloration, separation of constituents,
surface scum, or any other evidence of
contamination or breakdown.

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Liquid Penetrant
 Developer contamination ( Aqueous:
soluble and suspendable) accomplished
daily.
1) Checked for fluorescence, as
appropriate, and coverage by immersing an
aluminum panel. Failure to uniformly wet
the panel or any observed fluorescence is
unsatisfactory and the developer shall be
replaced.

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Liquid Penetrant
 Developer concentration – Aqueous soluble and
suspendable accomplished weekly.
1) Checked with a hydrometer to supplier
specification.
 Developer condition – (Dry) accomplished daily.
1) Check to see that the developer is fluffy and not
caked also check for fluorescent specks 10 or more
specks or any caking is unsatisfactory

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Liquid Penetrant
 Water wash pressure – checked each shift.
1) Should not exceed 40 psi, minimum
distance 12 inches from part. (need not be
recorded)
 Water Temp. – Checked each shift 50 to
100 degrees F.
Note: If immersion rinse is being used
the water should be agitated.

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Liquid Penetrant
 Black Light intensity – Checked daily.
1) Minimum 1000 micro watt/cm2 at 15 inches also
check filter for damage.
 Inspection area cleanliness – Checked daily (Need
not be recorded)
 Water based penetrant water concentration –
Checked weekly.
1) Checked with a refractometer to MFG.
Specifications.

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Liquid Penetrant
 Non-water based penetrant water content
(Method A) Checked monthly.
1)Test method D95 or Karl Fischer
method. 5% water content Max.
 Emulsifier concentration – (hydrophilic)
Checked weekly.
1) Checked with a refractometer to
MFG specifications.

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Liquid Penetrant
 Penetrant sensitivity – Checked weekly.
1) A comparison with unused sample if
the sensitivity drops below unused material
is unsatisfactory.
 Fluorescent brightness – Checked
quarterly.
1) Usually accomplished in a Lab. With
a fluorometer or a photofluorometer must
maintain 90% of original brightness.

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Liquid Penetrant
 Penetrant removability (Method A) –
Checked monthly.
1) Test shall by accomplished using
normal wash parameters compare with
unused material.
 Emulsifier removability – Checked
monthly.
1) Compare with unused material on
test piece or production part.

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Liquid Penetrant
 Emulsifier water content (lipophilic) –
Checked monthly.
1) Test method D95 or Karl Fischer
method usually sent to a Lab.
 Drying oven calibration – Checked
quarterly (may be reduced or extended
when substantiated by performance)

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Liquid Penetrant
 Light meter calibration – Checked
semiannually (may be reduced or extended
when substantiated)
1) Both black light and visible light
meters IAW MIL-STD-45662 or
ANSI/NCSL Z540-1

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Liquid Penetrant
 Preparing and Precleaning – All coatings
and other conditions such as paint, plating,
corrosion, scale, smeared metal, welding
flux, chemical residues or any other
material that could prevent from entering
discontinuities, suppress dye performance,
or produce unacceptable background.

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Magnetic Particle(ASTM E1444)
 Magnetic particle inspections can be
accomplished wet, dry, fluorescent, visible,
utilizing AC or DC current induced
magnetism in the circular, longitudinal
direction, or multidirectional.
 FAR part 145.49 you must have equipment
for wet and dry magnetic techniques,
residual and continuous methods and
portable for inspections of welds both on
or off the aircraft.

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Magnetic Particle
 Quality control and performance checks.
 Light intensity. Check daily
1) Black Light minimum intensity 1000
micro watt/cm2 also check filter for
damage.
2) Visible Light minimum 100fc or
1000 lx.
3) Ambient Light 2fc maximum.

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Magnetic Particle
 System performance using a test piece or ring
specimen. Check daily.
 Wet particle concentration. Check each shift –
Shall be .1 to .4ml in a 100ml sample fluorescent
particles. Shall be 1.2ml to 2.4ml for
nonfluorescent particles.
 Gauss meter (Teslameter) reading zero. Check
each use.
 Gauss meter (Teslameter) accuracy. 6 months.
 Ammeter accuracy. Check 6 months – usually
accomplished with a shunt and a calibrated
ammeter IAW MFG specifications +-10%.

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Magnetic Particle
 Quick break check. Check 6 months - can
use an oscilloscope or other method
recommended by the MFG.
 Dead weight check. Check 6 months –
Yokes and permanent magnets (when
allowed)
1) A.C. shall have a lifting force of at
least 10lbs with a 2 to 4 inch spacing.
2) D.C. lifting force 30lbs 2 to 4inch
spacing, or 50lbs 4 to 6inch spacing.

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Magnetic Particle
 Wet particle contamination. Check each
shift/ weekly.
1) Examine the the liquid above the
precipitate with a black light. fluorescence
should be comparable to original solution.
2) Examine the graduated portion of
the tube both visible light and black light
for striations or bands, different in color or
appearance this may indicate
contamination 30% maximum.

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Magnetic Particle
 Water break test. Check daily – Only on
water based vehicle with a wetting agent.
1) Flood the part with conditioned
water, and the appearance is noted after
flooding is stopped. If film of suspension
breaks, exposing bare surface, insufficient
wetting agent is present or the part has not
been cleaned properly.

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Magnetic Particle
 Preparation of parts.
1) Demagnetize the part before
examination if prior operations have
produced a residual magnetic field.
2)The surface of the part to be
inspected shall be smooth, clean, dry, and
free of oil, scale, machining marks, or
other contaminants or condition that might
interfere with the efficiency of the
inspection.

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Magnetic Particle
3) No coating that may prevent detection
of surface defects. Paint or chrome greater
than .003 inch in thickness, and
ferromagnetic coating such as
electroplated nickel greater than .001 inch

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Radiography
 Safety and exposure requirements are regulated
by the NRC and State agencies.
 Individual exposure should be maintained on
record at the facility.
 Industrial radiation license is issued by the state
and also thru the NRC for the use of a radioactive
isotopes.
 CFR 10 Parts 19, 20, 21, 30, 34 and 70 apply to
regulating and licensing for use of radioactive
isotopes.

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Radiography
 CFR 10 Part 19 regulations establish the
requirements for posting of notices, work
instructions and reports by licensees to
persons (employees) who participate in
licensed activities and options available to
employees in connection with NRC
inspections of licensees. Part 19
establishes the right and responsibilities of
individuals and the NRC on any matter
within the commissions jurisdiction.

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Radiography
 CFR 10 Part 20 establishes standards for
protection against radiation hazards arising
out of activity under licenses issued by the
NRC. Part 20 discusses the concept of
ALARA, and standards for dose limits for
all persons who receive, possess, use or
transfer material licensed under the NRC.

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Radiography
 CFR 10 Part 21 establishes reporting
procedures and requirements for any
individual or responsible officer of a firm
constructing, owning, operating or
supplying components licensed or
regulated by the NRC that fail to comply
with or regulations relating to safety. Part
21 establishes time limits for reporting to
the NRC when basic component defect or
failure pose a substantial hazard.

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Radiography
 CFR 10 Part 30 prescribes rules applicable
to all persons in the United States
governing domestic licensing of byproduct
material under the Atomic Energy Act of
1954, as amended, and Title II of the
Energy Reorganization Act of 1974.

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Radiography
 CFR 10 Part 34 establishes requirements
for the issuance of licenses for the use of
sealed sources containing byproduct
material and radiation requirements for
persons using such sealed sources in
radiography. Nothing in this part shall
apply to uses of byproduct material for
medical diagnosis or therapy.

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Radiography
 Part 34 cont. Includes requirements for
operating and emergency procedures, for
training of radiography personnel,
equipment performance, record
maintenance, securing and storing
radiographic exposure devices and
personal audits.
 CFR 10 Part 70 requirements for
packaging, preparation for shipment, and
transportation of licensed material.

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Radiography
 Radiation detection devices.
1) Survey Meter – Measures dose rate.
Gas filled tubes are used in the 2 types of
survey meters: the ionization chamber
survey meter and the Geiger-Muller
(or G-M) survey meter.
The Ion chamber survey meter is
primarily used. Survey meters should be
calibrated every 6 months (CFR 10 Part
34)

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Radiography
2) Pocket Dosimeter – The pocket dosimeter is
basically an air- filled ion chamber.The pocket
dosimeter uses a charger to apply an electric
charge to zero the quartz fiber as the dosimeter is
exposed to ionization radiation, the ions created
will neutralize the charge on the fiber and wire
causing the fiber to move toward the wire giving
a reading of exposure in milliroentgen (mR). The
pocket dosimeter should be calibrated every12
months.

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Radiography
3) Film Badge or TLD – Must be sent out
monthly to a certified Lab for reading, they
will send back a report of individual
exposure, which must become a part of the
individual personal exposure record.
4) Rate Alarm – Set to 500 mrem/hr.
calibrate every 12 months, may only be
required for use with isotopes.

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Radiography
 ALARA – Is an acronym for “as low as
reasonably achievable” which means make
every effort to maintain radiation exposures
as far below the dose limits as is practical.
 The radiation area shall maintained to a
maximum of 2 millirems.

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Radiography
 Storage of materials
1) Film should be stored in a cool dry
place on it’s end, the expiration date
should be on the box.
2) Chemicals (starter, fixer, and
developer) should be stored in an
appropriate locker. Most of these
chemicals have a 2 year life limit marked
on the box.

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Radiography
 Radiation Safety Officer.
1) The RSO is the individual with the
responsibility for overall radiation safety
program and who meets the requirements.
2) The RSO shall ensure that radiation safety
activities are being performed in accordance with
approved procedures and regulatory requirements
in the daily operation of the licensees program.
3) The RSO shall establish and oversee all
operating, emergency, and ALARA procedure.

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Radiography
 RSO cont.
4) Overseeing and approving all phases of
the training program for radiographic personnel.
5) Ensure that the required radiation surveys
and leak tests are performed and documented in
accordance with regulations.
6) Ensure that personal monitoring devices
are calibrated and used properly.
7)Ensuring that operations are conducted
safely and to assume control for instituting
corrective actions.

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Radiography
 Radiographer – should have had not only
the required amount of radiography
training, but should have also had training
in radiation safety. If the individual is
using radioactive isotopes must meet the
requirements of CFR10 Part 34.
 Radiographer Assistant – Should have
training in radiation safety and if using an
isotope must meet the requirements of
CFR 10 Part 34.

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Ultrasound
 Ultrasonic testing is the process of applying
ultrasonic sound (above 20,000Hz) to a specimen
and determining its soundness, thickness or some
physical property.
 Ultrasonic pulse echo instrument generates high
voltage electrical pulse of short duration. These
pulses are applied to the transducer which
converts them into mechanical vibrations that are
applied to the material.

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Ultrasound
 Ultrasonic through transmission –
Requires 2 transducers one for sending and
the other for receiving. Short or continuous
waves are transmitted into the material.The
quality of the material being tested is
measured in terms of energy lost by the
sound beam as it travels through the
material.

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Ultrasound
 Contact testing – Where the transducer is coupled
to the material through a thin layer of couplant.
 Immersion testing – Both the material and the
transducer are immersed in a tank of couplant
(usually water).
 Couplant – The primary purpose of a couplant is
to provide a suitable path between the transducer
and the test surface
 NOTE – Do not use glycerin as a couplant on
aluminum may cause corrosion

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Ultrasound
 Longitudinal wave – Have particle vibrations in a
back and forth motion in the direction of
propagation.
 Shear waves – Have particle vibrations
perpendicular to the direction of wave motion.
Shear waves will not travel through liquid or gas.
 Surface waves – Are elastic vibrations whose
energy is confined to a narrow region just below
the surface.

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Ultrasound
 Displaying ultrasonic indications – Three
basic types A-scan, B-scan, C-scan.
A-scan is a time versus amplitude
display which reveals a discontinuity using
a pip on a CRT. The A scan is read from
left to right.
B-scan typically uses an oscilloscope
type screen to display a cross sectional
view of the material being tested.

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Ultrasound
C-scan – Is a “Plan View” presentation
similar to an X-ray picture.The C-scan
shows shape and location of the
discontinuity but does not show depth.

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Ultrasound
 Calibration standards – Such as the IIW
block, Miniature calibration block, Area
amplitude blocks, DSC blocks and
Distance amplitude blocks.Calibration
standards are used for adjustments for
simple ultrasonic testing procedures and to
check on the reproducibility of
measurement.

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Ultrasound
 Reference standards – Aid in calibrating the
instrument and indicating whether the
discontinuities expected will be detected by
preselected sensitivity. The standards apart from
facilitating initial adjustment of the instrument,
also check on reproducibility of the
measurement.
 Reference standard material should be identical
to the object being tested in chemical
composition, heat treat, physical and mechanical
characteristics.

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Ultrasound
 Facility being evaluated should have the
appropriate standards, transducers,
equipment, technical data.
 To prepare a part for ultrasonic inspection
the part should be free of loose paint, dirt,
and scale.

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Eddy Current
 Eddy current testing is a non-destructive test
technique based on inducing electrical currents in
the material being inspected and observing the
interaction between those currents and the
material.
 Eddy Current can be used for crack detection,
conductivity measurement, nonconductive
coating thickness, material loss due to corrosion
 Indicating devices – An important part of the
eddy current test system is the part of the
instrument that gives the technician of the change
in impedance. As usual there are several different
types of devices used.

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Eddy Current
1) Analog meter
2) Digital meter
3) Oscilloscope
4) Impedance plane
5) Strip chart recorders

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Eddy Current
 Eddy Current Coils and Probes –
Inspection coils can have a variety of
forms and can be arranged in a variety of
ways. The choices of the type of
arrangement of the inspection coil depends
on the test situation.
1) Single coil absolute
2) double coil absolute
3) Differential coil arrangement
4) Reflection coil arrangement

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Eddy Current
 The previous coil arrangements can be installed
on a variety of probe configurations such as.
1) Surface probes
2) Holes probes
3) Encircling
4) Internal (bobbin)
 Erroneous indications can come from
nonspecific variations in the test object such as
coating thickness changes, conductivity
changes, even electrical interference.

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Eddy Current
 Reference standards – should be of the
same material chemical composition, heat
treat, physical and mechanical properties
as the part to be inspected.

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Eddy Current
 Conductivity measurements –
Conductivity measuring can be used to
determine a materials temper if you know
the alloy, it can be used to sort different
alloys, it can also be used to determine
heat damage on aluminum alloys.
Conductivity measurement alone can not
be used to identify different alloys due to
the overlap of conductivity ranges.

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Eddy Current
Conductivity cont. Accomplishing a
conductivity measurement is achieved by
using a conductivity instrument setting it
up with known calibration standards of
known value. A reading is given in %
IACS (International Annealed Copper
Standard) These standards should be
checked periodically for accuracy due
some materials conductivity changes with
age

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Eddy Current
 Conductivity cont. Another way is to make
a conductivity curve with an impedance
plane instrument utilizing the calibration
standard.
 Surface and subsurface defects can be
discovered using eddy current by using
different probe and coil configurations. As
a rule the lower the frequency used the
larger the depth of penetration.

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Eddy Current
 As with any other NDT method the facility
must have the appropriate equipment,
probes, standards, technical data and
trained personnel to perform the work.

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Summary
 In this class we have covered training and
certification, audit and evaluation and 5 of the
most commonly used NDT methods in general
terms.
 Read the vendors written practice, and look at the
specifications in which inspections are to be
accomplished Ensure that they have the required
materials to accomplish the work. While using
the 1A standard and a little familiarity with NDT
a thorough audit will be accomplished.

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Information
 Additional information on the subject of
NDT can be purchased from the ASNT at
asnt.org