UV Light Sanitizer

We can use UV light to sanitize our everyday objects – bed linen, towels, mobile phones, key chains and door handles to name a few. UV-C light is used to disinfect water in our water purifiers for a long time. UV light kills most pathogens and with sufficient exposure to the UV light, bacteria and Virus will be killed. I built a hand held , mains powered UV light Sanitizer with available parts in my garage. It is cheap to make and will easily last for a year and does its job quite effectively.

Step 1: UV Light Sanitizer

Ultra violet light has been used for a long time to irradiate and kill microbes – bacteria and virus. Sunlight contains a wide range of light spectrum and it is quite effective in killing harmful microorganisms and ward off gloom.

With Corona virus pandemic, we revisit sanitizers which can kill, immobilize and deactivate Viruses. UV light has been known to kill flu causing virus in the laboratories. As the Corona virus (CoV) is related to the family of virulent viruses which cause severe respiratory disease - from common cold to Middle East Respiratory Syndrome (MERS-CoV) and Severe Acute Respiratory Syndrome (SARS-CoV).

The best way to avoid COVID-19 infection is social distancing and sanitizing all exposed parts. Washing your hands with soap and using alcohol based sanitizers are recommended steps to prevent infection. But how do you sanitize our everyday objects – mobile phones, merchandise picked up from stores, cloths, linen , key chains and door knobs ?

You will need gallons of alcohol based sanitizers to do that. Sometimes it is not possible to use water or alcohol or any fluid to disinfect some objects. This is where an UV-C light comes in handy.

We can use UV light to sanitize our everyday objects – bed linen, towels, mobile phones, key chains and door handles to name a few.

UV-C light is used to disinfect water in our water purifiers for a long time. UV light kills most pathogens and with sufficient exposure to the UV light, bacteria and Virus will be killed. I built a hand held , mains powered UV light Sanitizer with available parts in my garage. It is cheap to make and will easily last for a year and does its job quite effectively.

Step 2: UV-C Light Sanitizer: What You Need

The UV-C light emitted by the small fluorescent bulb disinfects the objects placed before it. For maximum effectiveness, the object needs to be as close as possible to the light source and the duration of the exposure should be not less than 10 seconds. You can slowly move the UV Sanitizer over the object. When the bulb starts operating, it emits a dull bluish light. Don’t be fooled by the dim visible light output. Actually the UV light that it emits is powerful enough to kill the germs. Make sure that you don’t stare at the light. Same way don’t expose your skin to the UV-C radiation. They are harmful to your eyes and skin. The reason we build an enclosure is to protect our eyes and skin from the UV-C light.

Now that we have covered the theory, we will make a simple UV Light Sanitizer with easily available parts.

The main component is a Philips 11 W (TUV 11 W TL mini 4P SE) and its power supply kit usually sold for the domestic Reverse Osmosis Water Purifiers. We had that tucked away in our spares kit and we used what we had in our garage. You can improvise if you do not have exactly the same components listed here except in the UV light source.

Parts required:

1. 11 W UV Light Bulb (used in RO Water Purifiers)

2. Power supply kit supplied with the UV Light

3. Metal Tube or PVC Tube 3.5-4 in dia 13-14 in length

4. End caps 2

5. Kitchen foil as needed

6. 2 meter power supply cable terminated with a plug suitable for your country

7. Thick Leather gloves and UV resistant Goggles (optional)

Step 3: Method

Method:

1. Cut the PVC pipe to 30 cm (12 inch) length

2. Cut a slit in the center – 26 cms

3. Cut a slit in the opposite side – 26 cms

4. Cut the joint both ways ( See the images)

5. Glue kitchen foil in the inside

6. Mark the holes in the handle and screw the handle to the back of the PVC enclosure

7. Fix the lamp making sure that you don’t touch the glass. Use gloves to handle the bulb. Your hand will contain minute traces of oil which will smear the surface affecting the transmission of UV light. Besides traces of oil will attract dust particles.

8. Route the supply lines to the back and glue the power supply mini brick to the back of the PVC enclosure.

9. When you have completed all the steps, you should have a PVC enclosure that has the UV light inside which when operating leaves a dull bluish light reflecting from the object. At no point should you see the UV light directly.

Now use your newly minted UV light sanitizer to disinfect your daily use objects. Let's get rid of the dreaded COVID 19 virus.