When manufacturing threaded components that will be plated, it’s easy to overlook one critical factor: the coating adds thickness. That added material changes thread fit, function, and ultimately compliance with drawing requirements. To prevent costly rejects or rework, manufacturers calculate the pre-plate pitch diameter — the thread size before plating — to ensure that once the coating is applied, the finished thread meets its target class of fit.
Understanding how to properly calculate and verify pre-plate pitch diameters is essential for anyone in the thread manufacturing or calibration business. Whether you’re a machinist, quality engineer, or metrology lab technician, this process combines geometric principles, coating data, and gauging know-how.
Plating and coating processes, such as zinc, nickel, chrome, or cadmium, apply a uniform (or near-uniform) layer of material on all surfaces of a threaded part. While this layer improves corrosion resistance and appearance, it also alters the geometry of the threads:
If a manufacturer machines threads to the nominal (finished) size and then plates them, the result will likely be oversized external threads or undersized internal threads. Both conditions can cause interference fits or assembly issues.
To ensure that the finished (post-plate) thread falls within the required limits, you must calculate and machine the pre-plate thread undersize or oversize to compensate for the coating buildup.
You’ll need:
Because plating occurs on all thread flanks, the thickness affects both sides of the pitch diameter.
For external threads: PDpre=PDfinished−(4×T)PD_{pre} = PD_{finished} – (4 \times T)PDpre=PDfinished−(4×T)
For internal threads: PDpre=PDfinished+(4×T)PD_{pre} = PD_{finished} + (4 \times T)PDpre=PDfinished+(4×T)
Why the multiplier of 4?
Each flank of a 60° thread receives a coating thickness of T, but due to the flank angle, the effect on the pitch diameter is 2 × T × cos(30°) per side, or approximately 1.732 × T. For simplicity and conservatism, the industry uses 4 × T as a rule of thumb to ensure adequate compensation. For fine control, use the exact geometry-based relationship: ΔPD=2×T×1sin(30°)=4×T\Delta PD = 2 \times T \times \frac{1}{\sin(30°)} = 4 \times TΔPD=2×T×sin(30°)1=4×T
Let’s say we’re producing a ½-20 UNF-2A external thread that will receive 0.0002 in. of zinc plating per surface.
PDpre=0.4675−(4×0.0002)=0.4667 in.PD_{pre} = 0.4675 – (4 \times 0.0002) = 0.4667 \text{ in.}PDpre=0.4675−(4×0.0002)=0.4667 in.
Therefore, the thread should be cut to a pre-plate pitch diameter of 0.4667 in. to achieve a finished dimension of 0.4675 in. after plating.
Once you’ve calculated the pre-plate pitch diameter, verification through measurement is critical. There are two primary methods used in industry:
The three-wire method remains the most accurate way to determine pitch diameter on precision threads. It uses calibrated wires of known diameter placed in the thread flanks, and a micrometer measurement gives a “measurement over wires” (MOW) value. From this, pitch diameter is calculated using formulas from ASME B1.2 or ISO 1502.
For pre-plate verification:
Many manufacturers prefer GO/NO-GO thread ring or plug gauges for production checks. Pre-plate gauging often uses special pre-plate master gauges manufactured with the adjusted (pre-plate) dimensions. This ensures production threads are machined correctly before plating.
Walden Gage and other accredited gauge makers can produce pre-plate master setting plugs or rings to a specified target PD, ensuring the gauging aligns perfectly with plating requirements.
In practice, plating thickness is rarely perfectly uniform. Variations occur due to part geometry, process control, and current distribution. To manage this:
Even small deviations — on the order of 0.0001 in. — can shift a thread from Class 2A to a borderline 3A fit, affecting interchangeability.
Getting pre-plate pitch diameters right isn’t just a matter of arithmetic — it’s a quality-critical control that ensures functional thread fit after coating. By applying proper compensation formulas, verifying with accredited gauging, and maintaining control over plating variability, manufacturers can achieve consistent, compliant threads and reduce costly rework.
Whether you rely on three-wire measurement or fixed limit gauging, the key is consistency, traceability, and adherence to the latest ASME and ISO standards. Accurate pre-plate pitch diameter calculation is one more step in building confidence that what’s on the print is what’s in production — every time.
Posted on October 28.2025In thread inspection, the Go/No-Go gage has long been the trusted final word on whether a threaded component meets specification. But while many quality teams think of these fixed limit gages as simple “fit” indicators, their role is far more nuanced. Each pass or fail outcome is the result of a precise geometric relationship between the gage’s thread form and the part’s actual thread geometry.
Understanding how Go/No-Go gages interact with thread form integrity—not just pitch diameter—is critical for anyone responsible for maintaining quality in precision manufacturing. Subtle deviations in flank angle, lead, or profile truncation can produce misleading results, where a thread may technically “fit” but still fall short of its intended function.
Thread inspection often centers on the pitch diameter, the imaginary cylinder where the width of the thread ridge equals the width of the groove. While this is a key functional parameter, the Go/No-Go gage evaluates more than just size.
Because the gage’s thread form is manufactured to the same geometry as the nominal design, it simultaneously checks multiple elements at once:
If any of these elements deviate—even within small limits—the fit of the Go plug or No-Go ring gage will change. The gage may falsely indicate a pass if flank angle errors compensate for undersize pitch diameter, or vice versa. This interdependence is what makes gage calibration and proper use essential to accurate thread verification.
Each Go/No-Go inspection effectively performs a form comparison between two mating geometries. When a Go gage is inserted into a threaded component:
The opposite applies for external threads inspected with ring gages.
However, when a thread form deviates—for example, if the flank angle narrows slightly—the contact point between the gage and the part shifts. This changes the effective pitch diameter the gage perceives. A narrow flank angle can make a part appear “tight,” while a wide angle may cause premature acceptance of an undersized thread.
Similarly, lead variation or drunken threads (nonuniform pitch along the axis) can create localized tight spots. In such cases, the Go gage may enter smoothly at the start but bind deeper into engagement. While that might look like a simple dimensional issue, it actually signals a geometric inconsistency—a condition Go/No-Go gages are uniquely sensitive to, even when variable measurements miss it.
Under ISO/IEC 17025, calibration laboratories must demonstrate traceability of all measurement results to the International System of Units (SI). For Go/No-Go thread gages, this traceability chain connects back to national standards such as NIST Master Thread Gages in the United States or UKAS-accredited standards in the UK.
A properly accredited calibration ensures:
When a manufacturer uses ISO 17025–calibrated gages, each pass/fail result is traceable to an unbroken chain of standards. That means when a Go gage fits—or fails—it reflects not only dimensional accuracy but also internationally recognized thread form integrity.
(See: NIST Master Thread Plug and Ring Gages, ISO 1502:1996 – ISO Metric Screw Threads — Gauges and Gauging)
Even with well-calibrated tools, the interaction between gage and thread can be distorted by real-world factors:
A part can have a perfect pitch diameter and still fail in service if its thread form is off. Poor flank engagement reduces load-bearing area and leads to early stripping or fatigue failure. Conversely, overly truncated crests can cause excessive play, vibration, and leakage in pressure fittings.
In safety-critical industries like aerospace or medical devices, these small errors can have serious consequences. That’s why many quality engineers now supplement Go/No-Go gaging with form measurement techniques—such as optical thread scanners or coordinate measuring machines (CMMs)—to visualize the actual thread geometry.
Still, Go/No-Go gages remain the most practical and immediate method for verifying both size and form interaction on the shop floor. When properly calibrated and handled, they provide a remarkably sensitive indicator of real-world fit.
To get the most reliable results from Go/No-Go gages:
When these practices are combined with ISO 17025–accredited calibration, manufacturers can confidently rely on their Go/No-Go gages to detect even subtle thread form deviations before they cause costly rework or field failures.
Go/No-Go gages do much more than confirm if a thread “fits.” They are a mechanical expression of the complete thread geometry—flank, lead, truncation, and roundness—brought into physical contact with a precisely calibrated standard.
By understanding how these gages interact with thread form, and by maintaining traceable calibration under ISO/IEC 17025, manufacturers can ensure that every accepted thread is not only dimensionally correct but functionally sound. In an era of increasing precision and accountability, thread form integrity is the real measure of quality—and the humble Go/No-Go gage remains one of its most effective guardians.
Posted on October 27.2025
In any manufacturing process involving threaded components—bolts, nuts, threaded holes, tappet threads—the inspection of those threads is a critical control point. Using thread gauges correctly ensures you are making the right “attribute” decision: the part either meets the specification or it doesn’t. But simply handing a thread plug or ring gauge to an operator and expecting perfect results is risky. Today, we’ll walk through a systematic approach to proper usage of thread gauges, covering selection, setup, inspection technique, maintenance and calibration links to quality systems.
1. Select the correct gauge for the job
First and foremost: ensure you are using the right type of gauge for your threaded feature. There are two complementary styles:
Thread plug gauges (Go/No Go) for internal threads (nuts, tapped holes)
Thread ring gauges (Go/No Go) for external threads (bolts, studs)
Quality Magazine:
https://www.qualitymag.com/articles/94425-thread-basics-go-no-go-acceptance
Here are key selection pitfalls:
Matching the specification on the drawing exactly: thread size, series, class of fit (e.g., 2A/2B or 3A/3B) must correlate with the gauge you use. Using a 3B-class ring gauge on a 2A external thread is incorrect and can lead to bad parts passing or good parts rejected.
CrossCo:
https://www.crossco.com/resources/articles/mistakes-to-avoid-thread-gages
Understanding the difference between setting gages and working/wear check gages. Setting plugs or ring masters are calibrated to master standards and are not designed for production checking—they should not be used in place of a working Go or No-Go member.
CrossCo:
https://www.crossco.com/resources/articles/mistakes-to-avoid-thread-gages
Ensuring the gage reaches the required depth of thread in the part. For example, No-Go members must engage the thread for the correct number of turns (often 2½–3 turns) to validate size across length; if your part is shorter, you may need a special gage.
Quality Magazine:
https://www.qualitymag.com/articles/94425-thread-basics-go-no-go-acceptance
Matching materials and wear characteristics: if you’re gauging a hard material part, a standard tool-steel gage may wear prematurely and lead to mistaken acceptance. As one article advises: consider chrome‐plated or carbide gages for high usage/hard parts.
CrossCo:
https://www.crossco.com/resources/articles/mistakes-to-avoid-thread-gages/
2. Prepare the environment, instrument and part
Even the best gauge can give erroneous results if environmental, usage or handling conditions are sub-optimal. Key steps include:
Confirm that both the part and the gauge are at the calibration reference temperature (commonly 20 °C / 68 °F). Thermal expansion between the part and the gage can cause false rejects or false accepts.
https://elsmar.com/elsmarqualityforum/threads/controlled-environment-environmental-requirements-for-calibrations.16424
Clean the gage and the part: remove chips, burrs, lubricant residue, corrosion or debris that could interfere with thread engagement. A dirty or damaged thread surface can mask a size error.
Apply a thin film of appropriate lubricant on the gage to reduce friction and avoid galling, particularly for long threads or high-volume usage.
Inspect the gage for signs of wear, damage, chips or nicks before use. A gage with worn threads may incorrectly accept out-of-tolerance parts.
Make sure the part is properly fixtured/stabilized and aligns with the axis of the gauge insertion to avoid skewing the engagement or seating of the Go/No-Go feature.
3. Perform the inspection correctly
When you’re ready to inspect, follow a consistent method and record results (as applicable) for traceability.
Go member (should fit):
Insert or run the Go end of the gage with controlled hand force (avoid excessive torque or mechanical drive). The Go should engage fully to the depth required (or until the stop feature). If it does not fully enter, the thread is too small or not deep enough.
Quality Magazine:
https://www.qualitymag.com/articles/94425-thread-basics-go-no-go-acceptance
For internal threads, insert the Go plug and wind carefully—avoid forcing. For external threads, screw on the Go ring until it seats.
No-Go member (should not fit):
After the Go passes, attempt the No-Go. It must not fully engage beyond the allowed number of turns (commonly 2½–3 complete turns) or thread depth. If it does, the feature is too large or oversize.
Quality Magazine:
https://www.qualitymag.com/articles/94425-thread-basics-go-no-go-acceptance
Record the result: pass or fail. Ensure the decision point is clear: if Go passes and No-Go fails → part acceptable. Any other result → reject.
4. Review and interpret results
It’s important to treat this as an attribute gage decision—Go/No-Go is not providing you a dimension; it’s giving a “yes/no” outcome.
Walden Gage Calibration Services:
https://www.foxvalleymetrology.com/blog/thread-inspection-101-part-i-thread-gage-basics
Some additional considerations:
If many rejections occur, check the gauge (for wear/damage), check the process (machining, tapping, plating shrinkage) and confirm correct specification.
Periodically verify gage performance against a master or reference standard—even though the operator performs Go/No-Go, the gage itself must be verified in the calibration program.
Keep in mind that uncertainty of the measurement chain (including gage wear, environmental drift, operator variation) must be considered, especially when tolerances are tight. In some cases, measurement uncertainty may be a significant fraction of tolerance.
Quality Magazine:
https://www.qualitymag.com/articles/95656-dealing-with-measurement-uncertainty?
Record inspection data, traceability log of gages, calibration status, and any deviations—for internal audit and for linking to your accredited calibration system (e.g., ISO/IEC 17025).
5. Maintenance, calibration and lifecycle of thread gauges
Proper care and maintenance extend the life of your gauges and support your quality system. Consider the following:
Regular cleaning and protective coating (oil, wax film) after use, especially in humid or corrosive environments.
Store thread plug and ring gauges in protective cases or racks to avoid impact, deformation or contamination.
Inspect gages periodically: look for wear on Go ends (which typically wear faster) and on No-Go seating ends. Replace or re-calibrate when wear is evident.
Schedule calibrations at intervals based on usage, tolerance criticality, environment and history of wear. Some references indicate that for gages in heavy use or hard material parts, calibration and inspection frequency should increase.
Cutwel:
https://www.cutwel.co.uk/blog/thread-gauge-calibration?
Choose a calibration laboratory that is ISO/IEC 17025-accredited and has traceability to national standards. This ensures that your calibration results are accepted internally and externally, and you maintain the measurement traceability chain.
Document calibration certificates, gage identity, calibration interval, results including measurement uncertainty (which may be relatively large for thread gages).
Quality Magazine:
https://www.qualitymag.com/articles/95656-dealing-with-measurement-uncertainty?utm_source=chatgpt.com
6. Integrating with your quality system
From a management/quality‐systems perspective, incorporating thread gauge usage into your inspection procedure supports consistency, traceability and audit readiness:
Define a standard operating procedure (SOP) for thread gauging (selection, handling, inspection method, decision criteria, record keeping).
Train operators on correct gage usage—avoid common mistakes like forcing the gage, using the wrong class of fit, or using setting gages in production.
CrossCo
Maintain a gage log: include gage ID, size/class, calibration date, next due date, usage count (if tracked), wear history.
When changes occur (new part design, plating change, thread form change), review your gage inventory and ensure you still use the correct gauge or if a new/custom gage is required.
https://www.crossco.com/resources/articles/mistakes-to-avoid-thread-gages/
Monitor inspection results: a sudden increase in No-Go failures may indicate gage wear, process drift or incorrect gage use. Use this as a trigger for root-cause action.
Link the gage maintenance and calibration schedule to your quality system documentation (for example, referencing that your calibration provider is ISO/IEC 17025-accredited and maintains traceability). This links back to your audit readiness and continuity of measurement assurance.
Conclusion
Correct use of thread gauges is more than just handing them to an operator: it involves selecting the right gauge, setting up the environment and part, following a consistent inspection method, ensuring gage integrity and calibration, and embedding the process in your quality system. For manufacturers of threaded parts, these steps reduce risk, support measurement confidence, and improve production consistency. When your thread gages are well-managed and your operators well-trained, the Go/No-Go decision becomes a strong pillar of your inspection strategy rather than a weak link.
Posted on October 24.2025Go/No-Go Gages: The Unsung Heroes of Dimensional Quality Control
In the era of digital metrology and automated inspection systems, it’s easy to overlook one of manufacturing’s simplest yet most reliable quality tools: the Go/No-Go gage. Despite their apparent simplicity, these fixed-limit devices remain indispensable in high-volume production environments, where speed, repeatability, and conformance verification matter most.
From automotive and aerospace to medical and defense industries, Go/No-Go gages serve as the first line of dimensional defense – confirming whether a part meets design intent before it ever reaches final inspection.
A Go/No-Go gage is built around a binary measurement philosophy. Rather than indicating deviation from nominal, it simply answers the question: does the part conform to specification?
By applying both ends, inspectors can instantly verify compliance with a tolerance band, making Go/No-Go gages exceptionally efficient for shop-floor use.
For Go/No-Go gages to be effective, their calibration must be traceable to national or international standards. Accredited laboratories following ISO/IEC 17025 ensure controlled environmental conditions, proper uncertainty budgets, and documented traceability to NIST or equivalent standards. Accredited calibration isn’t just a formality – it safeguards the reliability of every Go/No-Go check performed on the shop floor.
Fixed-limit gages complement advanced technologies:
Go/No-Go gages may lack the sophistication of coordinate measuring systems, but their simplicity, durability, and reliability continue to make them invaluable in modern manufacturing. Whether under ISO 9001 or ISO/IEC 17025, fixed-limit gages quietly ensure dimensional quality remains under control.
Sources:
NIST: Dimensional Metrology
BIPM: International Vocabulary of Metrology
Quality Magazine: Dimensional Gaging Best Practices
ISO/IEC 17025: 2017 Standard Overview
NEWS
Ensuring Confidence with Go/No-Go Gauges: Calibration, Interval Strategy & Best Practices for ISO/IEC 17025 Labs
In today’s fast-paced manufacturing environment, attribute gauging tools such as Go/No-Go (fixed-limit) gauges remain a workhorse method for high-volume inspection of features of size. While the concept is straightforward – the “GO” member must pass, the “NO-GO” must not – ensuring traceable, reliable performance of these gauges requires a disciplined calibration and interval strategy, especially for a lab operating under the requirements of ISO/IEC 17025.
## 1. Understanding fixed-limit gauges and the metrology context
Fixed-limit gauges – often called Go/No-Go gauges – work by verifying that a part’s feature of size falls within defined limits. For example, a GO plug should fit the hole, while a NO-GO plug should not.
In the context of geometric dimensioning and tolerancing (GD&T), Go/No-Go gauges are frequently used to satisfy the Envelope Principle (Rule #1) for a feature of size – that the part feature must lie inside the perfect-form envelope at the Maximum Material Condition (MMC).
Because the gauges are fixed in limit, the tolerance of the gauge itself effectively consumes part of the part feature’s tolerance. A common guideline – the “10% rule” – states that the gauge tolerance (sum of GO and NO-GO tolerance) should not exceed about 10% of the part’s tolerance budget.
In practice:
– GO member sits at the minimum limit plus a small tolerance
– NO-GO member sits at the maximum limit minus a small tolerance
This ensures no bad part passes – albeit at the cost that some good parts at the extreme may be rejected.
From a metrology-lab viewpoint, these fixed-limit gauges must themselves be calibrated and traceable, often in an environment referenced to standards and under controlled conditions. For ISO/IEC 17025-accredited labs, that means documenting calibration procedures, measuring uncertainty, tracking wear, and managing intervals.
## 2. Calibration interval strategy: What drives it and how to justify it
For complex measuring equipment such as micrometers or CMMs, calibration intervals are derived from usage, stability, and risk. Attribute gauges like Go/No-Go should receive the same metrological rigor when inspection decisions carry quality risk.
Key drivers of interval selection include:
– Usage frequency – number of inspections per day
– Wear and damage risk – from burrs, drops, or contamination
– Impact of failure – product or process risk if gauge drifts
– Past calibration data – trends of drift and stability
– Environmental control – temperature, humidity, cleanliness
– Compliance – documentation required for ISO/IEC 17025 justification
Example: For a plug gauge inspecting a 1.0000 in +0.002/-0.000 hole, the 10% rule suggests a gauge tolerance of ±0.0001 in for GO and NO-GO members.
The calibration interval might begin at 12 months, shortened to 6 or 3 months if usage is heavy, the part critical, or wear-prone.
Documenting justification within the calibration system should include:
– Gauge ID and nominal size
– Tolerance and usage context
– Historical data and stability trends
– Risk assessment
– Chosen interval with rationale
This meets ISO/IEC 17025 requirements for traceability, uncertainty, and equipment management.
## 3. Best practices for Go/No-Go gauges in calibration labs
Best practices for maintaining reliability and compliance include:
– Ensure correct design and specification – apply the 10% rule.
– Label clearly – “GO” and “NO-GO” with nominal size, calibration and due date.
– Control storage and handling – protect from drops, forcing, or corrosion.
– Train operators – proper insertion technique and acceptance criteria.
– Inspect before use – check surfaces for wear, burrs, or contamination.
– Record usage and condition – maintain logs of inspections and incidents.
– Calibration process – measure against traceable standards, record uncertainty and conditions.
– Review and adjust intervals – refine based on trend and risk.
– Link inspection results to calibration health – rising rejects may indicate gauge drift.
## 4. Risk mitigation and value proposition
Using Go/No-Go gauges within a disciplined calibration program delivers both quality and cost benefits:
**Benefits include:**
– Speed and simplicity on the shop floor
– Prevention of defective parts from advancing
– Reduced calibration burden versus complex instruments
– Reinforced ISO/IEC 17025 credibility and audit readiness
**Risks when neglected:**
– Acceptance of bad parts due to gauge wear or drift
– Over-rejection of good parts due to tolerance consumption
– Audit or compliance failure if records or justification are missing
## 5. Practical implementation roadmap
**Step 1 – Inventory fixed-limit gauges:** Catalogue all Go/No-Go gauges (plugs, rings, thread, etc.) including size, tolerance, and calibration history.
**Step 2 – Classify by risk/usage:** Define categories such as critical, high-volume, or low-usage.
**Step 3 – Establish initial intervals:** Start with 12 months for low-risk, 6 months for high-risk; document rationale.
**Step 4 – Implement calibration procedure:** Follow ISO/IEC 17025-compliant methods; record uncertainty and environmental conditions.
**Step 5 – Monitor performance and usage logs:** Track inspection counts, rejects, and incidents.
**Step 6 – Review annually:** Analyze calibration data and adjust intervals as justified.
**Step 7 – Train and communicate:** Ensure all personnel understand gauge usage, calibration control, and value to the customer.
## Conclusion
While Go/No-Go gauges may appear simple, their proper management under ISO/IEC 17025 brings measurable benefits – improved yield, fewer defects, stronger audit readiness, and lower cost of quality.
Through interval justification, usage tracking, and calibration best practices, calibration labs can safeguard inspection processes and reinforce the credibility of their metrology programs.
Posted on October 21.2025
Digital caliper measuring tool with a black body and silver slider.
For many manufacturers, calibration certificates are trapped in PDFs and spreadsheets—hard to search, easy to misinterpret, and impossible to automate without custom scripts. Digital Calibration Certificates (DCCs) flip that script. By encoding calibrated values, uncertainties, traceability chains, and metadata in a standard, signed, machine-readable format, DCCs unlock straight-through processing from your calibration provider to your ERP, QMS, CMMS, SPC, and gauge management systems.
A DCC is a calibration certificate represented in a structured data format (commonly JSON or XML) with:
Several national metrology institutes and accreditation bodies have aligned on principles to make DCCs interoperable: consistent schemas, SI-based units, unambiguous identifiers, and validation signatures that survive system-to-system transfer.
ISO/IEC 17025 allows electronic certificates provided labs ensure integrity, authenticity, and readability for clients and regulators.
ILAC guidance emphasizes that electronic records/certificates are acceptable if controls maintain identity, integrity, and availability, and if content requirements for calibration certificates are met.
In practice, a DCC helps labs exceed “electronic certificate” expectations by adding structured semantics + signatures, not just a PDF.
Many accredited labs are experimenting with DCC exports. If a full DCC isn’t available, start with a hybrid: PDF + machine-readable attachment (JSON/XML) and a signature.
Ensure you can verify digital signatures and store the raw payloads.
Align DCC fields to your asset model (ID, family, location, process owner), decision rules, and due-date logic. Catalog gaps (e.g., missing serials, ambiguous unit codes) and agree on fixes with your lab.
Pick a mixed set (hand tools, plug gauges, thread rings, calipers). Measure benefits: ingestion time, data errors, out-of-tolerance response time, audit prep.
Maintain a set of trusted public keys/certificates from your labs and—where available—sector trust lists. Automate signature checks on receipt.
Feed as-found/as-left data into interval optimization and MSA. Use DCCs to refine risk-based intervals and to justify changes with objective evidence.
The long-awaited update to ISO/IEC 17025 has arrived. Released in late September 2025, the new edition of the standard modernizes the framework for competence in testing and calibration laboratories. As the backbone of global metrological confidence, this revision introduces new expectations around digital records, data integrity, sustainability, and risk-based thinking.
For calibration professionals and quality managers, understanding these updates early will make the upcoming transition smoother-and ensure continued trust in measurement results.
While the structure of the standard remains familiar, several key areas have evolved:
The 2025 update aligns with ISO’s sustainability goals, encouraging laboratories to document and reduce environmental impacts related to calibration activities-such as equipment energy consumption and waste disposal.
The updated standard reinforces a risk-based approach to personnel competence and equipment verification. Rather than rigid schedules, labs are encouraged to justify calibration intervals based on performance history and risk assessment.
To support mutual recognition, the new edition harmonizes terminology and competence principles across other conformity assessment standards, simplifying integration for multiscope organizations.
ILAC has announced a three-year transition period, meaning accredited labs must fully conform to ISO/IEC 17025:2025 by September 30, 2028. Early planning is crucial-especially for labs with large equipment inventories or complex LIMS systems.
Recommended actions:
Walden Gage helps manufacturers and calibration labs maintain confidence and compliance during this transition through:
Whether you’re preparing for reassessment or updating internal calibration plans, Walden Gage products are built to meet evolving quality system demands.
The 2025 revision of ISO/IEC 17025 underscores that calibration is not just about measurement-it’s about trust, data, and sustainability. Labs that embrace the digital and environmental elements early will not only comply, but lead.
Authoritative Source: NIST Handbook 150: ISO/IEC 17025
As tolerances tighten, unverified gauges can trigger defects, scrap, and audit findings. Establish a calibration program with clear intervals, control of records, and traceability to safeguard product quality and customer trust.
Review the full guidance from the source linked above and align your calibration intervals and documentation accordingly. Walden Gage can assess your current program and implement improvements that reduce risk and downtime.
Posted on October 10.2025
Walden Gage is always striving to provide our clients with access to the highest quality in all lines of fixed limit gaging. Spline Gaging is no exception. As far as fixed limit gages go, spline gages can be some of the most complex and difficult to design and build. After extensive research and investigation into the methods of manufacture and measurement Walden Gage is pleased to offer access to the nation’s best and brightest manufacturers of these comely measuring instruments. Please contact us today to learn more about how we can help you acquire your unique measurement solution!
Posted on July 26.2015
As a small business started in Connecticut, relocated to New York and expanded to include locations in New Hampshire Walden Gage has been focused on expanding the business to better serve you, our valued client. In recent months we have expanded our list of available resources to include familiar names such as Gage Assembly, Hemco Gages, Vermont Gage, PMC Lonestar and many more. Contact us today to learn more about out long list of available resources and new locations that may be coming to your area soon!
Posted on July 26.2015At Walden Gage, we are more than a supplier—we're your dedicated ally in achieving unparalleled accuracy and efficiency in precision measurement. With over 20 years of hands-on experience in the manufacturing industry, we specialize in delivering custom and complex fixed limit gauging solutions alongside ISO/IEC 17025-accredited calibration services. Our mission is to simplify your quality assurance processes by connecting you with the industry's most reliable tools and resources, ensuring your operations run smoothly without the hassle of vendor hunting or compliance worries. Whether you're dealing with intricate part geometries o
