Box UVC

UBee
DISCLAIMER
Ultraviolet light, its emitters and related equipment should be handled with care. Some risks involved are damage to living things or tissues via direct exposure, ozone generation or damages to certain materials (such as weakening or discoloration of some plastics). We advise to proceed with care and be informed, but we take no resposability for these or any other issues or damages that may arise when building or using this project.

UBee is a simple disinfectation kit based on UVC light for clearing bacteria and viruses from small tools and appliances used everyday.

UVC light is a “stronger” ultraviolet light, used for disinfectation of air, water and surfaces. Some examples would be biological samples, bottles, aquariums, etc. It’s out of the range of visible light for us humans, but other animals can perceive it (and even use it for signaling patterns).
The main motivation behind this project is providing tools for managing the impact of COVID-19 in our daily lives, although the uses can go beyond that.

SARS-CoV-2, the virus causing COVID-19 disease can stay viable (capable of causing a new infection) on surfaces for a considerable amount of time. This is specially dangerous in the case of items we carry everyday, so having a way of applying UVC to them is a way of combating spread and infection.
How does it work?
Ultraviolet light is short wavelenght electromagnetic radiation, with wavelengths ranging from 400 nm to 10 nm. UVC is a way of naming a segment of that range with shorter wavelengthts (between 280 and 100nm) as per the ISO-21348 standard.

Shorter wavelengths mean higher energy radiation, so even if ultraviolet is non-ionizing (can’t strip electrons from atoms) it can cause effects such as chemical reactions that interfere with structures related to life. It means exposure will end up killing small living things such as bacteria or fungi, or turn viruses into non-viable particles. On larger organisms (such as humans), repeated exposure can also have effects even if not on the shorter term, so caution is advised and not exposing your skin or eyes to it.

All things considered, it is a safe way of disinfecting air, water, surfaces or items without requiring direct manipulation of the medium and exposing it passively to UVC. By providing an enclosure to the source made out of wood and 3D printed parts, UBee makes the risks of handling UVC light more manageable.
Regarding the source, lightbulbs (or LEDs) emitting UVC are already used as part of disinfectation equipment. Some examples:
Biosafety cabinets
Aquariums
Feeding bottle cleaners

For UBee’s current iteration, a E14 UVC (around 280nm wavelenght) lightbulb composed of 112 LEDs is used. Inside the enclosure, we’ll use aluminium sheets (or other sheets wrapped in aluminium) plus additonal aluminium wrapping so it reflects the rays not hitting the target directly. Aluminium is great for reflecting UVC as it has + 90% reflectance.



The item will be held between UBee’s two halves thanks to a PEI 1mm sheet, as PEI is a material with high UVC transmittance (almost 90% for the range used on UBee).


Parts
1x IKEA MOPPE – 2x trays will be used from it
1x Hexagonal IKEA FIXA
1x 1mm thickness PEI sheet. Dimensions: 134mm x 163mm x 1mm
2x 0.25mm thickness aluminium sheet. Dimensions: 157mm x 190mm x 0.25mm
1x E14 Lightbulb socket (preferably with tulip adapter + cable + switch)
1x set of 3D printed parts (available inside the corresponding folder)
1x 220V E14 UVC lightbulb (112 LEDs)
Adhesive for wood and plastic (either double side tape or some glue)



Assembly
STEP 1
A hole must be drilled on one of the shorter side of one of the boxes. The hole diameter will depend on the lighbulb socket to be used.

The lighbulb socket must be then inserted and adjusted/fixed using the tulip adapter.



STEP 2
Lamp Fit and Regular will be inserted on the Sheet Holders. Then, using double sided adhesive tape, the Lamp Fit and Regular Fit are attached to both sides of the box, using the Sheet Holders as a reference.

Curve will be facing the bottom the box.



STEP 3
The 0.25 ~ 0.3 mm aluminium sheet will be slided into the holders, following the curve.

If aluminium sheet of that thickness are not available, one can be made by wrapping acetate or paper sheets using aluminium tape.

The PEI sheet is laid on top of the holders and on top of it, the Halves Connector.



STEP 4
Similar to STEP 2 and STEP 3, but using the top box and without a lighbulb.



STEP 5 (OPTIONAL)
FIXA feet are added to the Bottom Panel and that snaps to the bottom box using adhesive.



STEP 6 (OPTIONAL)
Top Panel is added to the top box using adhesive.



FINAL RESULT