SUSTAINABLE NDT
Regarding the July 2025 Materials
Evaluation article “Supporting
Sustainability for Nondestructive Testing,”
I appreciate the effort to bring sustain-
ability into the broader conversation within
NDT. It’s a timely and important topic, and
the article touches on several relevant
themes. That said, I believe a few areas
could benefit from further clarification or
balance—especially for readers who may
be less familiar with the practical and tech-
nical nuances of penetrant testing.
The article suggests that water-based
penetrants are naturally more environ-
mentally friendly than traditional oil- or
surfactant-based systems. However, this
isn’t always true. Water-based formulations
often include corrosion inhibitors, surfac-
tants, wetting agents, and other additives
that can make wastewater treatment more
complex and may require special disposal
measures. These formulations can also
be more costly to produce and manage,
so they are not necessarily cheaper just
because they contain water.
While water-based options can be
appropriate in some scenarios, they
are not universally more sustainable or
lower-impact than conventional pene-
trants—especially when full lifecycle
considerations (e.g., waste treatment, cost,
compatibility) are taken into account.
As a manufacturer, I agree that we
have a responsibility to continuously
improve our environmental and regu-
latory footprint. However, our ability to
do so is often constrained by customer
needs and specifications. Many end
users are tied to procedures that explic-
itly call out certain brands or products,
and changing those procedures typically
requires formal requalification, internal
approvals, and often third-party over-
sight. Environmental, Health, and Safety
(EHS) permits and fire department
regulations can further restrict allowable
chemistry.
The reality is that even when a more
“sustainable” option exists, customers
may not have the flexibility to implement
it without significant operational impact.
Finally, it may be worth clarifying that
AMS 2644 does not currently approve
any Level 3 or Level 4 water-based pene-
trants for final acceptance of aerospace
hardware—and it’s unlikely this will change
in the near future. These formulations
typically don’t meet the performance and
durability requirements demanded by
high-sensitivity inspections in aerospace.
I share this feedback in the spirit of
professional collaboration. Sustainability
is a conversation we all need to be part
of, and I appreciate ASNT’s initiative in
bringing these topics to the forefront.
That said, a follow-up piece or clarification
could go a long way in helping readers
understand the practical challenges that
both manufacturers and users face when
it comes to implementing more sustain-
able practices in NDT—especially in high-
spec or highly regulated environments.
Thanks for all the work you do to
elevate the industry and promote
dialogue on important issues.
PETER PELAYO
ASNT NDT LEVEL III (MT/PT)/NAS 410 LEVEL 3
LOS ALAMITOS, CA
LETTERS
|
SCANNER
done through three working groups:
Parts Tracking, Data Analytics, and
Aircraft-on-Ground (AOG) Support.
There has been a spate of recent news
stories regarding the prevalence of fake
parts or falsified airworthiness certificates
for aircraft engines and other systems.
Having the means to digitally track indi-
vidual parts from birth to disposal, and
allowing stakeholders the necessary
access to these records, would help alle-
viate some of the issues related to such
counterfeiting. This critical aspect of MRO
is being undertaken by the Parts Tracking
working group.
The Data Analytics working group is
developing governance standards for the
legal and fair sharing of operational data
among key aviation participants. These
include OEMs, operators, component
and system manufacturers, and MRO
vendors—and, due to the regulatory envi-
ronment, also the regulators. One of the
most interesting problems being tackled
by this working group is how to analyze
operational data to get to the root cause
of technical issues when the data is scat-
tered across multiple sovereignties (i.e.,
stored on servers in different countries
where the operators or MROs reside).
This challenge becomes even more
complex when the solutions to these
technical issues are based on AI algo-
rithms that depend on a preponderance
of data to converge on the right answers.
In addition to the technical barriers, there
are serious data governance issues that
must be resolved to make these solutions
feasible—that is where the IDCA’s work
comes in.
Finally, the AOG Support working
group is focused on developing data-
sharing standards that will allow different
airlines and parts suppliers (both manu-
facturers and distributors) to exchange
the required parts data, along with all
the necessary paperwork, in a timely
manner, so that an aircraft stranded in a
remote location can get back in the air in
the shortest possible time. In these cases,
the IDCA’s goal is to develop and publish
industry-consensus standards that allow
seamless access to necessary data by
authorized parties, so that inefficiencies
in the system are reduced and needless
contractual barriers are eliminated.
AUTHOR
Ravi Rajamani, PhD: drR2 Consulting
ravi@drr2-consulting.com
ADDITIONAL RESOURCES
EU Data Act, https://digital-strategy.ec
.europa.eu/en/policies/data-act.
Independent Data Consortium for Aviation
(IDCA) Issue Papers, www.dataforaviation.
org/issue-papers-toc.
SAE AIR7161: Guidance for Digital Thread
Data Standards Enablement, Monitoring,
and Quantification with the Digital Thread
Framework and Digital Thread Index, https://
www.sae.org/standards/content/air7161.
NDE OUTLOOK FROM P. 14
NDE Outlook focuses on possibility thinking
for NDT and NDE. Topics may include technology
trends, research in progress, or calls to action. To
contribute, please contact Associate Technical Editor
Ripi Singh at ripi@inspiringnext.com.
A U G U S T 2 0 2 5 • M AT E R I A L S E V A L U AT I O N 15
Regarding the July 2025 Materials
Evaluation article “Supporting
Sustainability for Nondestructive Testing,”
I appreciate the effort to bring sustain-
ability into the broader conversation within
NDT. It’s a timely and important topic, and
the article touches on several relevant
themes. That said, I believe a few areas
could benefit from further clarification or
balance—especially for readers who may
be less familiar with the practical and tech-
nical nuances of penetrant testing.
The article suggests that water-based
penetrants are naturally more environ-
mentally friendly than traditional oil- or
surfactant-based systems. However, this
isn’t always true. Water-based formulations
often include corrosion inhibitors, surfac-
tants, wetting agents, and other additives
that can make wastewater treatment more
complex and may require special disposal
measures. These formulations can also
be more costly to produce and manage,
so they are not necessarily cheaper just
because they contain water.
While water-based options can be
appropriate in some scenarios, they
are not universally more sustainable or
lower-impact than conventional pene-
trants—especially when full lifecycle
considerations (e.g., waste treatment, cost,
compatibility) are taken into account.
As a manufacturer, I agree that we
have a responsibility to continuously
improve our environmental and regu-
latory footprint. However, our ability to
do so is often constrained by customer
needs and specifications. Many end
users are tied to procedures that explic-
itly call out certain brands or products,
and changing those procedures typically
requires formal requalification, internal
approvals, and often third-party over-
sight. Environmental, Health, and Safety
(EHS) permits and fire department
regulations can further restrict allowable
chemistry.
The reality is that even when a more
“sustainable” option exists, customers
may not have the flexibility to implement
it without significant operational impact.
Finally, it may be worth clarifying that
AMS 2644 does not currently approve
any Level 3 or Level 4 water-based pene-
trants for final acceptance of aerospace
hardware—and it’s unlikely this will change
in the near future. These formulations
typically don’t meet the performance and
durability requirements demanded by
high-sensitivity inspections in aerospace.
I share this feedback in the spirit of
professional collaboration. Sustainability
is a conversation we all need to be part
of, and I appreciate ASNT’s initiative in
bringing these topics to the forefront.
That said, a follow-up piece or clarification
could go a long way in helping readers
understand the practical challenges that
both manufacturers and users face when
it comes to implementing more sustain-
able practices in NDT—especially in high-
spec or highly regulated environments.
Thanks for all the work you do to
elevate the industry and promote
dialogue on important issues.
PETER PELAYO
ASNT NDT LEVEL III (MT/PT)/NAS 410 LEVEL 3
LOS ALAMITOS, CA
LETTERS
|
SCANNER
done through three working groups:
Parts Tracking, Data Analytics, and
Aircraft-on-Ground (AOG) Support.
There has been a spate of recent news
stories regarding the prevalence of fake
parts or falsified airworthiness certificates
for aircraft engines and other systems.
Having the means to digitally track indi-
vidual parts from birth to disposal, and
allowing stakeholders the necessary
access to these records, would help alle-
viate some of the issues related to such
counterfeiting. This critical aspect of MRO
is being undertaken by the Parts Tracking
working group.
The Data Analytics working group is
developing governance standards for the
legal and fair sharing of operational data
among key aviation participants. These
include OEMs, operators, component
and system manufacturers, and MRO
vendors—and, due to the regulatory envi-
ronment, also the regulators. One of the
most interesting problems being tackled
by this working group is how to analyze
operational data to get to the root cause
of technical issues when the data is scat-
tered across multiple sovereignties (i.e.,
stored on servers in different countries
where the operators or MROs reside).
This challenge becomes even more
complex when the solutions to these
technical issues are based on AI algo-
rithms that depend on a preponderance
of data to converge on the right answers.
In addition to the technical barriers, there
are serious data governance issues that
must be resolved to make these solutions
feasible—that is where the IDCA’s work
comes in.
Finally, the AOG Support working
group is focused on developing data-
sharing standards that will allow different
airlines and parts suppliers (both manu-
facturers and distributors) to exchange
the required parts data, along with all
the necessary paperwork, in a timely
manner, so that an aircraft stranded in a
remote location can get back in the air in
the shortest possible time. In these cases,
the IDCA’s goal is to develop and publish
industry-consensus standards that allow
seamless access to necessary data by
authorized parties, so that inefficiencies
in the system are reduced and needless
contractual barriers are eliminated.
AUTHOR
Ravi Rajamani, PhD: drR2 Consulting
ravi@drr2-consulting.com
ADDITIONAL RESOURCES
EU Data Act, https://digital-strategy.ec
.europa.eu/en/policies/data-act.
Independent Data Consortium for Aviation
(IDCA) Issue Papers, www.dataforaviation.
org/issue-papers-toc.
SAE AIR7161: Guidance for Digital Thread
Data Standards Enablement, Monitoring,
and Quantification with the Digital Thread
Framework and Digital Thread Index, https://
www.sae.org/standards/content/air7161.
NDE OUTLOOK FROM P. 14
NDE Outlook focuses on possibility thinking
for NDT and NDE. Topics may include technology
trends, research in progress, or calls to action. To
contribute, please contact Associate Technical Editor
Ripi Singh at ripi@inspiringnext.com.
A U G U S T 2 0 2 5 • M AT E R I A L S E V A L U AT I O N 15
