TEN350 The waveform that hijacked the IEC lightning standards

Welcome to the TEN350.com website

If you've been involved in lightning protection in 90% of the world's countries, it is almost a certainty that the concept of the 10/350 waveform has been foisted upon you without your consent. You may not know it, but its origins have been purposefully hidden, its true significance misrepresented, and its lack of workability casually ignored. This website fills in the missing pieces, sets the record straight on vital data, and lifts the veil on some rather uncomfortable issues.


The information on this website is provided as a public service solely for educational and informational purposes. Permission is granted to download, display, print and reproduce this material in an unaltered form for personal non-commercial use or for use within your organization.

11 slides on the home page link to the main subject pages. Further links at the bottom of the home page, plus the navigation buttons at the top of every page, allow you to move around the site. Many references can be accessed by clicking on the underlined sections of the text.

WEBSITE MISSION: The goal of this website is to improve the quality of lightning surge protection by:

  • • Documenting how the 10/350 waveform and so-called “Class 1 Test” have severely damaged the workability of IEC lightning protection standards.
  • • Unveiling the true origin of the 10/350 waveform. (It’s not what you have been told.)
  • • Annotating how CIGRE’S 2013 Technical Brochure 549 denies any possible basis for using a 10/350 waveform test.
  • • Documenting some of the earlier turmoil on this subject. Some of the original, hard to find, documents are made available for those who wish to go more deeply into the past record.
  • • Reminding one and all that surge protection can be workable and effective when not encumbered by a bad-hat monkey such as the 10/350 waveform.

Don't take anything in this website on faith.

If you've been an advocate of the 10/350 waveform or the Class 1 Test, we suggest you start off by examining the method by which you reached your conclusions about these things and then listing the facts on which those conclusions rest. After that, study the information provided on this web, compare it to your own experience, and decide for yourself how soundly based were those earlier conclusions.

We thank you for visiting and wish you luck in improving the state of lightning protection in your area.

The image below shows the past 20 years' of LPS (lightning protection suffocation.) Roll your mouse over it to see what happens in the next 20 years.


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