Covid-19: can a UV-C source be improvised from a standard mercury vapor lamp?

Question

I suggest it because the usual professional UV-C sources are in short supply and very costly.

A common 175 W mercury lamp designed for illumination includes the quartz 'lamp' tube itself, inside an outer bulb designed to block UV-C (< 300 nm) radiation. If the outer bulb were removed, this kind of lamp would seem to be able to provide UV-C to destroy a virus.

I don't have a UV-C capable spectrometer nor a power meter filtered for UV-C only, so I can't test/do the experiment myself. Maybe someone else has such gear.

A document on this is here, and it includes references. I do not suggest that this be done except by those who understand the hazards of the experiment.

I believe that it's better to throw an idea on the table in front of engineers and technicians, than to hide ideas that may be helpful or to post untried projects on hack sites and prepper forums where they may do more harm than good. Known hazards include: UV radiation, high voltage, high temperature, broken glass.

If someone has the gear to try it, maybe it could help the situation.

The document is here, somewat hidden by obscurity.

ADDED 4/3/ 2020: I should have stated that my goal was primarily to disinfect masks for re-use. I didn't want to limit the scope, being more interested in spectrum and power per square area at given distance.

I too, worked with an e-prom eraser, but from a repair perspective. The original UV tube was broken and unavailable. I put in two UV-C germicidal lamps. It worked perfectly and saved the customer money.

Some masks can be treated by heat or chemicals, and some may contain materials that are ruined quickly or are not properly disinfected by those and other methods. The type and construction of mask will dictate the best way to disinfect it for maximum re-use.

Treating every surface of an arbitrarily shaped object with sufficient UV intensity for sufficient time is a challenge. It's not impossible. Two UV lamps could be used, or a rotisserie arrangement, using an alligator clip to hold a mask, or any other arrangement, may be worthwhile. We can use our imaginations.

The risk of transmission from handling objects is significant and supported by expert opinion of an experienced doctor, James Robb, MD FCAP, here.

There was, and will not be, any suggestion whatsoever that anyone get some Covid-19 Coronavirus and irradiate it, then try to prove it’s worked. There are experts in the field who know how much UV-C intensity per area and irradiation time is required to inactivate the virus. There is such information for other viruses online.

While there are no studies specifically on Covid-19, Ozone has been shown to kill the SARS Coronavirus. Ozone is unstable and wants to revert to O2 and lose the third Oxygen atom. If the third atom of Oxygen does not find another Oxygen atom to combine with, it can break the virus so that it can't function. While Ozone can damage some materials, it does disinfect them. There are several references, to scholarly work, in online articles to support the statement made in the comment. Link1 to references and Link2 to references

At least one paper states that atomic Oxygen can recombine in a time scale of a few milliseconds. Our senses and the above references tell us that it can be produced in copious enough amounts to be effective in spite of this.

Solutions don't have to be clever, they only have to be workable. A Dallas, Texas mattress-cleaning company is already using its production line to sterilize masks for hospitals. It seems obvious but it's extending the lifetime of disposable masks from 1 day to > a week.

What the UV (and Ozone comment) information may mean for the public, who may soon be told to wear masks or face coverings outdoors, that that a mask could be safely used for a very long time. Ozone generation is another topic.

I clarify that I am not posting here for any pecuniary purpose. I have only one old set of PPE. Unfortunately it is only effective on October 31. A bit of levity keeps me motivated.

Answer 1

Yes, but only for killing viruses in the near vicinity. Not to use it when live people, animals are nearby. Also it would accelerate ageing of colours, plastics, wood,...Not a very clever solution, but if desperately needed could be a way to go.

Answer 2

You mentioned the cost. The UV filters for residential well-water systems are reasonable. I assume they'd work for viruses too. As said above, it is, of course, dangerous to living tissue, so modifications and use would have to be done properly.

Answer 3

If i get the question correctly: Those lamps have the proper wavelength according the Wikipedia:

And for covid19 from 250 to 285 nm (UVC ) could be fine. also You needs to have minimum energy which could be like this:

Headgear-mers virus is one of RNA viruses and are categorized together should dose between 15–400 Ws/m2 . Examples of well-known RNA virus doses are 110 Ws poliovirus/m2 , Newcastle disease 15 Ws/m2 SARS 226 Ws/m2 . The assessment measured in the same region as high SARS can calculate real-time inactivity like to achieve 90% [3, 9].

The LED UVC have more life time like this:

Also here you can see about UVC bulbs:

There are cheaper ways to generate disinfecting UV light. For example, mercury lamps have been used to disinfect surfaces and liquids for decades, and the bulbs are only about $100. However, they are 25,000 times less intense than a Xenon bulb and the disinfection process can take hours, making them impractical for hospital use. LEDs could also provide cheaper UV light, but they are also far less intense than Xenon bulbs, according to Hart [5, 11] (Fig. 8).

Also consider there Smart Dosage could be fine which is described here:

Built Patent SmartDosage, together with the patented box Balance and PowerBoost technology allow iris 3200 m UV lighting system of disinfection for automatically measuring conditions the room environment, such as the size of the room, temperature and humidity in order to determine in real time the appropriate dose, time, number and power of the lamp is required for complete disinfection of all while providing maximum power permitted in the United States for the production of germicidal UVC energy.

I think it could be used also, This book is good for this propose.