Four standards govern two distinct levels: how thickness measurement is carried out and how it is verified that the instrument used to carry it out is up to the task.
- ✓ EN 14127 and ISO 16809: the principles of direct-contact measurement
- ✓ ASTM E797: the American practice of the contact pulse-echo method
- ✓ EN 15317: verification of the performance of the thickness gauge
- ✓ The declared conformities are given on the page of each model
The first group of standards describes the method. EN 14127 and ISO 16809 establish the principles of ultrasonic thickness measurement on metallic and non-metallic materials, based solely on measuring the time of flight of the ultrasonic pulses; ASTM E797 provides the guidelines for the contact pulse-echo method according to American practice.
The second group concerns the instrument. EN 15317 specifies methods and acceptance criteria for evaluating the performance of equipment that measures thickness with pulse-echo ultrasound: it is the standard referred to when it is necessary to demonstrate that the thickness gauge used is suitable, and not just that it was used correctly.
Need help choosing the right product?
The distinction matters in daily practice. A client who disputes a report may question the method followed or the instrument used: these are two different objections, and they are answered with different standards. Knowing which standard governs which level is the quickest way to close the discussion.
The standards in this section
| Standard | What it governs |
|---|---|
| EN 14127 | Principles of ultrasonic thickness measurement by direct contact |
| ASTM E797 | Practice for measurement with the contact pulse-echo method |
| EN 15317 | Characterisation and verification of ultrasonic thickness gauges |
| ISO 16809 | ISO standard on the ultrasonic determination of thickness |
Where Dakota NDT instruments stand
Several models of the Dakota NDT range state in their documentation conformity to ASTM E797, EN 14127 and EN 15317. The declaration applies to the individual model: you will find it on the product page and in the attached datasheet, not as a generic characteristic of the brand.
Alongside the conformity of the instrument comes the validity of the calibration, documented by the NIST-traceable calibration certificate. The details of the service are described on the Calibration page.
Frequently asked questions
EN 14127 concerns the measuring method, that is, how ultrasonic thickness measurement is carried out. EN 15317 instead concerns the instrument: it specifies methods and acceptance criteria for evaluating its performance.
They are two distinct standards, one European and one ISO, dealing with the same subject: the principles of ultrasonic thickness measurement based on the time of flight of the pulses. ISO 16809 was updated in 2025, an edition that took the title of ultrasonic determination of thickness.
On the product page of the model and in the attached datasheet. Declarations of conformity and EMC reports can be requested from us via the Contact page.
Go back to NDT Technologies and Standards or write to us from the Contact page.
Further information and contacts
Systems division and sensor integration partner : www.roder.it
More information about RODER SRL : about us
Contact for general information : info@roder.it
Contact for information about these products : info@roder.it
The information contained on this web page is provided for information purposes only. Although it has been compiled with the utmost care, it does not constitute a contractual offer or a binding commitment to supply. It may contain transcription, translation or typographical errors. For precise and up-to-date information, please contact our company directly.
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