Ad and revenue policy
This site is free. The domain, the hosting and the hours that go into it are not. Below is how the site earns money, what I accept and what I do not.
Affiliate links
The Udemy links in the recommended courses section are affiliate links. If you buy a course through one of them, Udemy pays me a small share. It costs you nothing extra. Those links are marked rel="sponsored" in the page source.
I do not teach the courses on that list and I am not responsible for what is in them. I quote their ratings and student numbers as they appeared on Udemy on the day I added them; those numbers move over time.
Advertising
Ads on this site are served by Google AdSense. Google chooses where they go, which means an ad can appear on any page, the calculators and the fault tree included. I switched it on knowing that, because it is what keeps the site standing.
But if an ad slows a page down, covers the content, or gets in your way while you are working, write to me: [email protected]. I will shut that placement off. Ad revenue does not come before a technician being able to use a page comfortably on site.
Google and its partners may serve ads based on your earlier visits here or elsewhere, using cookies. You can switch off personalised ads at Google ad settings.
Sponsorship and consulting
I may accept sponsorship or consulting offers from companies. If that happens, it is stated plainly on the page concerned. As these lines are written there is no active sponsorship agreement.
What I do not accept
I do not change a technical opinion for money. I will not describe a manufacturer’s product differently from how I have found it in the field. The fault tree, the status code library and the calculators are manufacturer-independent and will stay that way; no sponsor goes into them. I do not write favourable reviews in exchange for payment.
Measurement
Traffic is measured with Cloudflare Web Analytics, which uses no cookies and collects no personal data. Glossary searches that return nothing are logged as a counter so I can see which terms are missing; nothing is kept about who searched. Full detail: privacy policy.
Questions or objections
If anything here looks off to you, write: [email protected]
Last updated: 9 September 2026