Turn the machine on. (Make sure the door is in the closed position. – If it is not, turn the machine off and start again).
To start the process, push the main button
as shown above. The door will open and be ready to accept whatever part needs to be sterilized.
With the door open and the part in the machine, push the same button again and the door will close. When the door closes, the blue light above the start button will turn on and the UV sterilization will begin. The light remains on for 10 seconds with the door closed and then automatically opens when the process is complete.
Remove the part from the machine. There is a sensor that triggers as you remove the part and the door will automatically close 3 seconds after that sensor is triggered when the part is removed.
1. Staphylococcus Aureus
2. Escherichia Coli
3. Pseudomonous Aeruginosa
4. Enterococci Faecalis
5. Clostridium Difficile
1. Testing completed on glass trays at different distances from the UV bulb to determine where the tray should be located to accomplish the needed level of sterilization for the marketplace.
The samples were counted on their respective coupons before the exposure and then recounted after exposure. They are reported in a log reduction format because the amount of the organism is in the hundreds of thousands. For example, some of the coupons had 1 x10^5 amount of an organism which is a quantity of 100000. This means that in order to market a specific percent reduction, the following can be assumed:
Log reduction Number of cfus Percentage reduction Times smaller
0 log (Log0) 1 000 000 0% N/A
1 log (Log1) 100 000 90% x 10
2 log (Log2) 10 000 99% x 100
3 log (Log3) 1 000 99.9% x 1 000
4 log (Log4) 100 99.99% x 10 000
5 log (Log5) 10 99.999% x 100 000
6 log (Log6) 1 99.9999% x 1 000 000
Currently we tested a log reduction for 4 distances/time periods on each of the 5 organisms.
• 10 seconds Direct Exposure 1 inch from UV (On a tray)
• 10 seconds Direct Exposure 3 inch from UV (On a tray)
• 10 seconds Direct Exposure 5 inch from UV (at bottom of box)
• 10 seconds Indirect Exposure 5 inch from UV (at bottom of box)-Requires light to reflect off other surfaces
• 30 seconds Direct Exposure 1 inch from UV (On a tray)- Sanity check
We need to determine whether 99.99% is our acceptability criteria
For Staph. Aureus
• 10 seconds Direct Exposure 1 inch from UV (On a tray) – 4.1 log - 99.99%
• 10 seconds Direct Exposure 3 inch from UV (On a tray) – Not tested
• 10 seconds Direct Exposure 5 inch from UV (at bottom of box) – 3.4 Log - 99.9%
• 10 seconds Indirect Exposure 5 inch from UV (at bottom of box)- 2.1 log - 99%
• 30 seconds Direct Exposure 1 inch from UV (On a tray)- 5.5 log – 99.999%
For Escherichia Coli, Pseudomonous Aeruginosa, Enterococci Faecalis, and Clostridium Difficile there was a 4 log reduction at 1 inch and 3 inch distances. Waiting for the actual reductions at the others distances.