Well written. However, the tests in your report were performed totally incorrectly.
You say that you used "a calibrated 254 nm UV-C light source". The videos show that this was a cheap (non-germicidal) LED UVC lamp of the type UVGO that can be bought on eBay: https://www.ebay.com/itm/315790301232
There is no guarantee or proof that this cheap LED was calibrated.
On the other hand, your measuring radiometers were LS126C and LS127C UV Light Meters, calibrated by the manufacturer Linshang specifically for investigation of low-density mercury UV sources, and low-density mercury UV germicidal lamps, respectively: https://www.linshangtech.com/product/LS126C_EN.html
Thus their UV intensities/doses must be measured by radiometers calibrated specifically for each type of the lamp.
In summary, your tests performed using Intellego's dosimeters which were previously tested and validated independently by the RISE institute of Sweden, show that indeed, electronic radiometers designed for use with low-density mercury lamps grossly overestimate the dose of UV radiation that LED UV sources produce. This result is not surprising and has nothing to do with the quality of Intellego's dosimeter cards.
We appreciate the feedback and agree that getting UV measurements right isn’t as simple as it sounds. That said, our research is explicitly focused on our on-the-ground observations in China, where all UV-measuring instruments (including both our Radiometers) are calibrated according to JJG 879-2015 《外辐射照度计检定规程》（Verification Regulation of Ultraviolet Radiometers), the country’s official national standard for UV irradiance meters. We are not comparing our research to any observations by the RISE Institute of Sweden or any other third parties.
OK, thank you for accepting the criticism. Thus, we agree that you used wrong combination of UV lamp and radiometers. Note that I didn’t doubt that radiometers had been calibrated at the factory (i.e. to match the spectral profile of mercury lamps). But the manufacturer clearly stated that they should be used for low-pressure mercury lamps only, which you totally ignored.
The recent investigation of Intellego has brought me here, and as someone in the field, I have some criticism of your criticism, if you'll allow me. The spectral response of the radiometers are stated to be between 230-280 nm, with the highest sensitivity around 254 nm. This shows a pretty narrow band, so the rest of the mercury spectrum shouldn't be measurable. Considering how strong the 254 nm peak in a low pressure Hg lamp is, a 254 nm LED should be able to replicate it very well, and a radiometer with such wavelength selectivity shouldn't show much variation between the two.
But, the question of the quality of the LED itself is still in question. However, I don't see why the Intellego strips would be *less* sensitive to another wavelength than a conventional electronic radiometer. I would expect the Intellego strips to have a broader sensitivity range, and therefore show a higher dose for, say, 280 nm UV light than the radiometers, if that were the case.
Did you contact/listen/read transcripts of recently departed Henkel employees' thoughts on Intellego and its products with which they have firsthand experience?
I realize that Europe (and basically anything non-Asia distribution) isn't the region that you focus on.
China companies violate agreements & contracts oftentimes (and pirating/"fakes" abound), especially with Western companies. This is a sharp contrast to Europe/US contractual norms.
Great fieldwork - I will need to verify your conclusions, but for now, I agree with the part about trust needing to be earned twice, by doing what they say. We'll find out both very soon. https://www.sleepwellinvestments.com/p/intellego-was-a-mistake
Well written. However, the tests in your report were performed totally incorrectly.
You say that you used "a calibrated 254 nm UV-C light source". The videos show that this was a cheap (non-germicidal) LED UVC lamp of the type UVGO that can be bought on eBay: https://www.ebay.com/itm/315790301232
There is no guarantee or proof that this cheap LED was calibrated.
On the other hand, your measuring radiometers were LS126C and LS127C UV Light Meters, calibrated by the manufacturer Linshang specifically for investigation of low-density mercury UV sources, and low-density mercury UV germicidal lamps, respectively: https://www.linshangtech.com/product/LS126C_EN.html
https://www.linshangtech.com/product/ls127c-integrated-uv-light-meter.html
It is known that low-density mercury UV sources have a completely different spectral profile compared to LED UV sources:
https://www.opsytec.com/uv-applications-knowledge/spectral-database-for-uv-lamps-and-uv-leds
Thus their UV intensities/doses must be measured by radiometers calibrated specifically for each type of the lamp.
In summary, your tests performed using Intellego's dosimeters which were previously tested and validated independently by the RISE institute of Sweden, show that indeed, electronic radiometers designed for use with low-density mercury lamps grossly overestimate the dose of UV radiation that LED UV sources produce. This result is not surprising and has nothing to do with the quality of Intellego's dosimeter cards.
We appreciate the feedback and agree that getting UV measurements right isn’t as simple as it sounds. That said, our research is explicitly focused on our on-the-ground observations in China, where all UV-measuring instruments (including both our Radiometers) are calibrated according to JJG 879-2015 《外辐射照度计检定规程》（Verification Regulation of Ultraviolet Radiometers), the country’s official national standard for UV irradiance meters. We are not comparing our research to any observations by the RISE Institute of Sweden or any other third parties.
OK, thank you for accepting the criticism. Thus, we agree that you used wrong combination of UV lamp and radiometers. Note that I didn’t doubt that radiometers had been calibrated at the factory (i.e. to match the spectral profile of mercury lamps). But the manufacturer clearly stated that they should be used for low-pressure mercury lamps only, which you totally ignored.
The recent investigation of Intellego has brought me here, and as someone in the field, I have some criticism of your criticism, if you'll allow me. The spectral response of the radiometers are stated to be between 230-280 nm, with the highest sensitivity around 254 nm. This shows a pretty narrow band, so the rest of the mercury spectrum shouldn't be measurable. Considering how strong the 254 nm peak in a low pressure Hg lamp is, a 254 nm LED should be able to replicate it very well, and a radiometer with such wavelength selectivity shouldn't show much variation between the two.
But, the question of the quality of the LED itself is still in question. However, I don't see why the Intellego strips would be *less* sensitive to another wavelength than a conventional electronic radiometer. I would expect the Intellego strips to have a broader sensitivity range, and therefore show a higher dose for, say, 280 nm UV light than the radiometers, if that were the case.
Did you contact/listen/read transcripts of recently departed Henkel employees' thoughts on Intellego and its products with which they have firsthand experience?
I realize that Europe (and basically anything non-Asia distribution) isn't the region that you focus on.
China companies violate agreements & contracts oftentimes (and pirating/"fakes" abound), especially with Western companies. This is a sharp contrast to Europe/US contractual norms.
Great fieldwork - I will need to verify your conclusions, but for now, I agree with the part about trust needing to be earned twice, by doing what they say. We'll find out both very soon. https://www.sleepwellinvestments.com/p/intellego-was-a-mistake
Wow, you really put in a lot of effort. Congrats!
Thorough work of independent research!
Incredible research nice work!
this is amazing work. very thorough.
Amazing, first proper research on INT!
Amazing work!
Likewise!
great work !
got here from @SWI comment, and loved every sentence.
Superb investigative efforts!
Tomorrow may be a fun day for you.