Since the pandemic arose, there have been many ineffective, fake or scam UV-C LED disinfection lamps suddenly flooding Amazon, Ebay, Xiaomi and the Singapore online market. In other words, it’s best to buy from a reputable, well-known source.
There a few factors to watch out for and take into considerations if you are thinking about buying a disinfection robot for your business or for your household. Product specifications will state the wavelength (nm), though it doesn’t necessarily mean they are accurate.
UV light covers a wavelength spectrum from 100 to 380 nm and is subdivided into three regions by wavelength: UVA (320 to 400 nm), UVB (280 to 320 nm), and UVC (200 to 280 nm). Optimum disinfection UV-C wavelength is at 260nm to 280nm.

1. UV-C LED lights do not emit a visible light
If there is only one light source and there is a colour like purple or black, it likely is not emitting UV-C light or not emitting the right UV light (UV-A and UV-B wavelengths). In some products like the O-RX disinfection autonomous robot, there usually is one emitting regular light, the other, presumably, emitting UV-C. The regular light source allows you to know that the UV-C light source is on.
2. UV-C LED output is too low
This is harder to check as you need the right equipment to calculate the output. With a UV-C light that has too low output, it’s likely it isn’t disinfecting anything. Taking into consideration volume of space, the distance between the light source and elapsed time. Doubling the power does not mean that the UV output will double.
3. Real semiconductor (LED) products cost more than a regular strip LED
If you are buying a UV-C light bar claiming to disinfect for $7, it’s likely to be a fake UV-C LED light. Proper disinfection UV-C LEDs are made from a quartz or glass lens’ optic and housed in ceramic or aluminum. Plastic may end up burning and degrading. Many LEDs with the wrong wavelength sold online are with a plastic lens/optic.
4. UV-C light is harmful to the naked eye
Any UV-C disinfection products selling wands or lamps that you can hold, is harmful to the naked eye and should only be used when you are out the room. There have been reports where the wrong UV light used in products has caused bodily harm.
The UV-C LED lights used in OTSAW’s O-RX disinfection robot, are used in a patented process that is the world’s first laboratory tested autonomous robot, achieving a disinfection efficacy of 99.99% within 5 minutes, at a range of 2.5 meters and is able to cover 4000 sq ft of disinfection area in one hour.