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(author)

I'm really glad that you're making and selling far-UVC products. Nukit is the other manufacturer (aside from Aerolamp) that I feature on https://www.faruvc.org

I really hope that your thesis is correct, and we end up with widespread low cost high quality unencumbered far-UVC. In my looking, though, it seems like bulb life is an issue? Is that right, or have I been snookered by Ushio's marketing?


Well, one reason KrCl lamp life became an issue is that they are not replaceable in any commercially available filtered Far-UVC fixture. Currently, at the end of the KrCl excimer lamp life- typically 3000-5000 hours, you throw the entire Far-UVC device away- filters, ballast, control electronics- the whole thing in the trash. There is some talk of possible refurbishment, but at high cost with no companies really in place offering it.

There's really no excuse for this but planned obsolescence. Replaceable light bulbs are 140-year-old legacy tech and trivial to engineer.

Needless to say, this was a major stumbling block for institutional buyers- having to buy and reinstall ~$5000 worth of Far-UVC for a small room every year or two. At which point virtually every Far-UVC company started claiming everything from 5,000 hours to 20,000 hours operating life- with absolutely no data to support this. Some cite in-house testing, but no real evidence is offered.

Given that fraudulent claims in the Far-UVC industry are common, there's every reason not to trust marketing claims that aren't backed by third-party tests. If you don't have a test that proves it, don't say it. (We urge our customers to trust no one, not even us. "Trust" has no place with potentially dangerous UV devices- everything must be third-party lab tested).

A KrCl excimer lamp that could exceed the current, widely documented 3,000-5,000hr (30% degradation or L70) operating life would be huge news and we'd love to see it. But there would be patents, papers, independent lab tests, some paper trail other than manufacturer claims to support this.

Right now, it's all "trust me bro" marketing with perhaps bit of hedging about possibly using reduced power or limited operating time to increase lamp life. By the time buyers have reached 5,000 hours, the products are well out of warranty, and they are left without recourse. If someone says anything about their Far-UVC lasting more than 5,000 hours, the correct response is "Citation?".

In the absence of any credible data showing that anyone is getting an L70 over 5,000 hours of use in the real world at 100% power and uptime, we've chosen to focus on low-cost, non-IP-encumbered, replaceable bulbs, and all of our future products will use them. Any other manufacturer is welcome to use them as well, with the hope that this will get Far-UVC ownership down to the "rice cooker or oscillating fan" price range needed for those in the most desperate need. Because until everyone is protected, no one is. We're all just a cough and a plane ride from each other.


Here is a paper showing that the USHIO care222 module achieves an L70 of at least 10,000 hours: https://www.jstage.jst.go.jp/article/lsj/50/7/50_394/_pdf

Here is a poster with more data in the same series, showing that the L70 is about 13,500 hours: https://cdn.shopify.com/s/files/1/0694/8637/9189/files/24061...

I have never seen any other data for any other commercially available krypton-chloride excimer lamp besides this paper and this poster. All that is "widely documented" is manufacturers claims. The non-USHIO KrCl excimer lamps I have personally tested had L70s closer to 1000 hours, nowhere near 3000-5000 hours. Of course since I am involved in Aerolamp I am not a credible third party, but I am not asking anyone to believe me, I am simply explaining why I decline to believe this 3000-5000 hour claim that is presently without any substantiation whatsoever, not even a paper or conference poster.

Of course, a cheap 1000-hour bulb that is easy to replace and available from multiple manufacturers is great! For many people this approach makes sense. But it is not a 3000-5000 hour bulb and consumers need to know that in order to replace their bulbs in a timely fashion.

You will probably say that the paper and poster and is not credible third party data. This is why Aerolamp has submitted multiple samples to LightLab Allentown for lifetime testing. Perhaps you would be willing to do the same, given how frequently you emphasize the importance of third-party data?


>Here is a paper showing that the USHIO care222 module achieves an L70 of at least 10,000 hours: https://www.jstage.jst.go.jp/article/lsj/50/7/50_394/_pdf

The scientists who wrote this paper work directly for Ushio, correct? And it has not been replicated or verified in any way?

>I am simply explaining why I decline to believe this 3000-5000 hour claim that is presently without any substantiation whatsoever

Very sensible, it should be checked also and claims until then retracted.

>This is why Aerolamp has submitted multiple samples to LightLab Allentown for lifetime testing. Perhaps you would be willing to do the same, given how frequently you emphasize the importance of third-party data?

Sounds like a great idea, we have multiple new gas formulations to test and low-cost replaceable bulbs mean it will be easy to offer customers greater operating life as we improve them. Perhaps Aerolamp would also like to refrain from making any claims without third party data as well? It would be a good example for us to set.


That's really interesting; I had thought it was just the high CO2 was a proxy for greater occupancy, but it does look like there is a physical effect.

https://www.nature.com/articles/s41467-024-47777-5


Yes, it's due to changing the pH of water in the air.

And skin damage


(author)

The non-profit OSLUV evaluates lamps and measures their emissions. Here's their evaluation for the Aerolamp, which is the one I've purchased: https://reports.osluv.org/static/assay/aerolamp%20devkit--27...


OSLUV is fantastic; doing great work.


This isn't the kind of thing you can do with a license, as long as training a model doesn't require a license. Now, that's an open question legally in the US, and there are active lawsuits, but that does seem like the way it's most likely to play out.

Why do you think there's was an implicit agreement that documentation was only intended for humans? I've written a lot of documentation, much of it open source, and I'm generally very excited that it has proved additionally useful via LLMs. If you had asked me in 2010 whether that was something I intended in writing docs I'm pretty sure I would have said something like "that's science fiction, but sure".

You still intended it for humans. Intent is defined by what one is aiming for, and without knowledge of an alternative, that was your intent.

100% I get that you are OK with it being used by non-human ingestion. And I think many might be OK with that.

One thing, I'm not sure how helpful the documentation is. I think we're getting training out of example, not docs. This makes me think... we could test this by creating a new pseudo-language, and then provide no examples, only docs.

If the LLM can then code effectively after reading the docs, we'd have a successful test. Otherwise? It's all parroting.


(author)

This absolutely depends on the frequency of UVC and the intensity of the lamp. The lamps this post links such as https://aerolamp.net are putting out 222-nm, which is much safer than longer UVC wavelengths and the intensity is well under TLV when placed 8.5ft up (or higher).

See https://www.faruvc.org for more on eye safety.


They can leak into higher wavelengths. You are really putting a whole lot of trust in manufacturers if you are sitting underneath one of these for decades with unprotected eyes. Not a risk I would take personally (I have glaucoma already, so I'm a bit more sensitive than the average person about eye health)

Ah nice, their data sheet has a spectrum. Kind of odd that they don't market the "we filter out the harmful parts" feature more prominently.

Kinda like advertising "Asbestos-Free Cereal" isn't it? If someone was marketing a product to me and they were super insistent about how super duper safe it was I would probably start getting suspicious

UV rightfully raises concerns about skin damage, highlighting that they're careful about excluding the harmful parts would be helpful for customers who either know just enough to think "UV bad" or to those who wonder how narrow their filters are.

Imo a better analogy would be selling a circular saw with a safety mechanism and hiding the latter in the specsheet.


No, it's more like advertising asbestos-free talc.

Many manufacturers refuse to post third party spectral assays detailing safety and power output, it's a big problem.

> I have not seen the pyramid with bread, cereal, rice and pasta at the base pushed for at least ~20 years.

Thats right. It was replaced 20 years ago by https://en.wikipedia.org/wiki/MyPyramid


Ahh. Maybe because I'm AU-based millennial, but the only "food pyramid" I was aware of was the grains-heavy 90s one that I would randomly see here and there, so that was my point of reference.

That is what I found on my quick search too. I am pretty sure I saw some alternatives to the bread, ... based pyramid before 2005 as well.

> the first one was in 1982 or something

The first one came out in 1992, and was active until MyPyramid came out in 2005. Which was then active until MyPlate came out in 2011.


you're correct, my eyesight gets worse as the day goes on and i saw the second "9" as an 8. that only partially reduces the impact from my claim of X, Millennial, Zoomer; as i am gen X and i was still in "middle school" when the food pyramid came out, and my millennial sister assuredly was. the older Gen X (from the early 1970s) may or may not remember (as in an only child and childless until after the poster was no longer used) this from their younger years in classrooms.

My main point was (i think!) that really the only people seeing these posters on a regular basis are schoolchildren. I think i've seen the pyramid a dozen times in the last 20 years, on cereal boxes or websites or whatever, but if you don't recognize it, it's easily written off. Maslow also had a pyramid, etc.


I would be interested in knowing what cereal box you saw it on or where you saw it promoted seriously in the last 20 years.

In the late 90s I was in high school in a town with less that 80k people in the middle of the congenital USA and the pyramid with bread, cereal, rice and pasta at the base was not seriously pushed, or taken seriously, at school or when it came up outside of school.


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