VISUAL TESTING METHOD PERSONNEL
QUALIFICATION AND CERTIFICATION:
AN OVERVIEW
BY MIKE ALLGAIER
Most major nondestructive testing (NDT) personnel qualification and
certification (PQ&C) schema address visual testing (VT) as a standalone
NDT method. However, there are significant differences between the
details of these elements. Various codes, standards, and specifications
delineate various requirements for personnel education, experience,
training, and examination of the candidates for certification. This article
addresses the common elements needed for PQ&C across different
codes, standards, and guidelines.
Introduction
Visual testing (VT) has long been
integral to other NDT methods, as it his-
torically has served as a prerequisite for
those methods. It was a prerequisite to
liquid penetrant testing (PT), magnetic
particle testing (MT), ultrasonic testing
(UT), and radiographic testing (RT)
when it was stated in those methods that
“surface conditions that would inter-
fere with the examination should be
evaluated and removed.” Level I/II cer-
tification took for granted that the pre-
requisite to PT and MT included the VT
knowledge and skills.
The VT method has gained its
own method status over the last 50
years. Early VT tools included the
human eye, a magnifying glass, a
dental mirror, a 6-in. steel scale, a
12-in. wooden ruler, and maybe a 50-ft
tape measure. Today, how to examine
an object has changed. The advent
of digital imaging has offered a great
expanse in the variety of instruments
available to capture digital images and
allow analysis of the part condition,
including measurement techniques
that are more and more sophisticated.
Remote visual inspection, also known
as RVI, can be used to inspect areas of
infrastructure from a distance that are
too dangerous, remote, or inaccessible
for direct visual inspection. RVI tech-
nologies include remotely operated
cameras, borescopes, videoscopes,
fiberscopes, and drones.
Background
When exploring PQ&C schema for VT,
we discover two major categories. The
first is direct VT (DVT) and the second
is indirect VT, more commonly referred
to as RVI.
The DVT examination definition
taken from the ASME Boiler and
Pressure Vessel Code, Section V:
Nondestructive Examination, Article 9,
Visual Examination, states that the eye
should be within 24 in. of the surface to
be examined and at an angle not less
than 30°. This can include aids such as
a magnifier or mirror. The term “aid”
implies that the surface can be inspected
without these tools, hence the direct
method of VT.
RVI is used when the above
criteria for DVT cannot be met—for
example, when the surface under
inspection is only accessible with a
mirror, a magnifying glass, a series
of lenses in a borescope, a bundle of
fibers, a charge-coupled device trans-
mitting the image to a monitor (such
as a videoscope), or a telescope for
long-distance inspections.
With either category for evaluat-
ing hardware, there are three pillars, or
goals:
Ñ to acquire an acceptable image,
Ñ to evaluate the part, component, or
system test results, and
Ñ to disposition those test results to the
appropriate acceptance or recording
criteria.
To perform these steps, the inspec-
tor or examiner needs to possess the
core knowledge and basic skills for
common applications. In addition,
industry-specific knowledge and skills
unique to various industries, products,
or VT techniques are also required.
These are called industry specific
segments (ISS). When comparing
various industry PQ&C requirements, we
observe overlaps, omissions, and unique
criteria across different programs. Some
VT requirements are common across all
industries, while others are unique to
certain ISS.
Elements of Personnel Qualification
and Certification
Proper execution and evaluation of any
VT application requires the inspector
or examiner to be qualified in the VT
method using the applicable techniques.
Compliance with those qualifications,
along with written documentation and
a summary sheet, is known as certifica-
tion. Following are a few of the common
schema for VT PQ&C used in the NDT
industry.
American Society for
Nondestructive Testing (ASNT)
The original recommendations for NDT
PQ&C date back to 1968 with the publi-
cation of ASNT Recommended Practice
No. SNT-TC-1A: Personnel Qualification
FEATURE
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VT
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and Certification in Nondestructive Testing.
Its main distinction is that it is a guide-
line, not a standard. It provides guide-
lines for employers to establish in-house
certification programs for the qualifica-
tion and certification of NDT personnel
and provides education, experience, and
training recommendations for each NDT
method. Therefore, the primary driver is
the employer’s written practice, which
can vary across individual companies.
When an employer has a contract
with a customer, the customer’s spec-
ification will call out the primary stan-
dards, codes, and regulations that
must be complied with to satisfactorily
complete the contract. Originally, SNT-
TC-1A had its own body-of-knowledge
outline referenced for each NDT method
as a supplement, but it was up to the
employer to modify the program to
suit their needs. Training content and
duration would be especially subject
to customization by each employer.
SNT-TC-1A provides the recommended
number of training hours in a table (see
Table 1 for VT recommendations).
Today, ANSI/ASNT CP-105: ASNT
Standard Topical Outlines for Qualification
of Nondestructive Testing Personnel spec-
ifies the body of knowledge to be used
as part of a training program qualify-
ing and certifying NDT personnel. It
applies to personnel whose tasks or jobs
require knowledge of the technical prin-
ciples underlying the NDT methods for
which they have responsibility. These
tasks include performing, specifying,
reviewing, monitoring, supervising, and
evaluating NDT work. These outlines
are approved by the American National
Standards Institute (hence the ANSI in
its title).
ANSI/ASNT CP-189: ASNT Standard
for Qualification and Certification of
Nondestructive Testing Personnel is a
standard for qualification and certifica-
tion of NDT personnel. Its main distinc-
tion is that it is a standard, not a recom-
mended practice. It builds on SNT-TC-1A
by providing comprehensive minimum
requirements for personnel certifica-
tion, such as requirements for NDT
instructors and employer certification of
Level I, II, and III personnel as well as a
requirement for the ASNT NDT Level III
certification of Level III personnel. This
standard is approved by ANSI and also
references CP-105 for training outlines.
When CP-189 is referenced in a contract,
the vendor, contractor, or prime must
meet the requirements listed therein.
The common certification elements
addressed in both the guideline
(SNT-TC-1A) and the standard (CP-189)
include education, training, experience,
and exams. Exams include three types:
physical (visual acuity) exams, written
exams, and practical exams.
American Petroleum Institute (API)
API has its own requirements for vessel
inspection, including VT. API 510, API
570, API 653, and API 1169 (note: this
list is not exhaustive) each have their
own checklists of what to inspect for in
internal and external visual inspections.
Vessels, piping, new piping construction,
tanks, and the like have broader scope
inspection requirements than surface
conditions alone. Licensed inspectors
must be utilized to prevent catastrophic
failures or unexpected operational
issues. This article does not address the
petrochemical specifics for inspection
PQ&C.
American Welding Society (AWS)
Prior education typically does not
decrease the requirements for VT Level
I or II in terms of experience, training,
physical exams, written exams, or prac-
tical exams (proficiency demonstra-
tions). However, the AWS certification
for Certified Weld Inspector (CWI) does
adjust the experience requirements
based on an individual’s education. The
more education one has, the less experi-
ence is needed to obtain CWI certifica-
tion. In this comparison, CWI is treated
as equivalent to SNT-TC-1A or CP-189
Level II.
Table 2 shows the minimum edu-
cation and work experience required to
become a CWI per AWS.
Training
All these PQ&C programs require
training. NDT requires skilled and quali-
fied personnel to perform, interpret, and
evaluate the tests. Training and certify-
ing NDT personnel can help ensure the
accuracy, reliability, and validity of NDT
results. Moreover, training and certify-
ing NDT personnel can help company
owners reduce the risk of errors, acci-
dents, and liabilities. Furthermore,
training and certifying NDT personnel
can help improve their competence,
confidence, and motivation.
The industry can choose from
various NDT training and certification
T A B L E 2
Education and work experience required to
become a CWI, per AWS
If the candidate has:
The amount of
experience required
is:
4-year bachelor’s degree 1 year
2-year associate degree 2 years
Eng/tech courses 3 years
Vo-tech courses 4 years
High school 5 years
8th grade 9 years
8th grade 12 years
Note: This concept also applies to NDT Level IIIs in SNT-TC-
1A, where higher education levels can reduce the required
amount of experience.
T A B L E 1
Recommended initial training and experience levels for VT*
Examination method NDT level Training hours
Minimum hours
in method or
technique
Total hours in
NDT
Visual testing (VT)
I 8 70 130
II 16 140 270
*per SNT-TC-1A (2024), excerpted from Table 6.3.1A
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