InSight

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UV Dosage for Disinfection


May 6, 2020 8:22:19 AM

Education Products Industry Ultraviolet

 

Viruses, bacteria, mold, and other pathogens are now stopped dead in their tracks with XtraLight's UV-C High Power Ultraviolet Disinfection System. Follow these steps when using this effective and powerful light which emits 254 nm wavelengths. The results will amaze you and give you peace of mind. 

 

UVC STEPS TO DISINFECTION:

STEPS:

  1. FOLLOW SAFETY GUIDELINES
  2. UNDERSTAND BASIC UVC TERMS
  3. IDENTIFY UV DOSE
  4. SURVEY AREA TO BE DISINFECTED
  5. CALCULATE ESTIMATED UV EXPOSURE TIME FOR DISINFECTING
  6. DISINFECT AREA AND VALIDATE WITH DOSIMETER CARDS

All surfaces within a certain distance will observe an assured level of disinfection in a certain amount of time as long as the wavelengths are not blocked from accessing the surface.

 


 

STEP 1

FOLLOW SAFETY GUIDELINES

 

Do's

Don’t​'s

  • Protect your eyes
  • Use protective PPE gear
  • Establish a plan to disinfect area 
  • Use safety timers
  • Train personnel in using UVC disinfecting system
  • Use hazard warning signs when in use
  • Keep fixture in protective case
  • Don’t expose eyes & skin to UVC
  • Don’t allow anyone to operate UVC fixture without reading safety instructions
  • Don’t allow anyone into area being treated with UVC
  • Don't touch the UVC lamps while operating

  • Excessive exposure to UVC can cause adverse effects on the eyes, retina, skin, circadian system, and immune system.
  • Human over exposure causes temporary skin redness and harsh eye irritation.
  • Symptoms may take 4 to 24 hours to occur after exposure.

 

STEP 2

UNDERSTANDING BASIC UVC TERMS​     

Log reduction exampleRADIANT EXPOSUREJ/m2 or mJ/cm2

  • UV INTENSITY (I) = energy per unit surface area
  • EXPOSURE TIME (T) = exposure time in seconds
  • UV DOSE (FLUENCE) =  Intensity (I) x Time (T) expressed as mJ/cm2
LOG REDUCTION =  percentage of microorganisms inactivated 
  • EXAMPLE:
    a 1 log reduction will reduce the pathogen by 90%, before the UVC disinfection
    a 2 log reduction will reduce the pathogen by 99%, etc 

 

STEP 3

IDENTIFY UV DOSE

  • IDENTIFY TARGETED MICROORGANISMS
  • PAIR WITH LOG REDUCTION.   

    PATHOGENS

    Common Name

    Scientific Name

    3 Log Reduction

    Viruses

    Rota

    Rotaviruses (Human)

    32 mJ/cm2 

    Infectious Hepatitis

    Hepatitis B

    25 mJ/cm2 

    Adenovirus

     

    126 mJ/cm2 

    ECHO Virus

    Echovirus

    25 mJ/cm2 

    Bacteria

    Salmonella

    Salmonella Typhimurium

    22 mJ/cm2 

    Staph

    Staphylococcus aureus

    3.2 mJ/cm2 

    (2 log)

    Strep

    Streptococcus faecalis

    9.8 mJ/cm2 

  • UV dose determines what proportion of a specific microorganism is destroyed after a particular dose of UV radiation

    Target 50 mJ/cm2 to deactivate the average bacteria/virus

    Example from Log Reduction

Log reduction exampleExample from Log Reduction                  Download UV Dose Log Reduction Guide


 

STEP 4

SURVEY AREA TO BE DISINFECTED

Our testing Data:

 

XLM

Product

UV Intensity

Exposure Time

Radiance Exposure

Distance

Handheld

2.8 mJ/cm2

17 sec

50mJ/cm2

4 in.

Mobile

.34 mJ/cm2

6 min

50mJ/cm2

5 ft

Mobile

.08  mJ/cm2

17 min

50mJ/cm2

10 ft

Mobile

.03 mJ/cm2

28 min

50mJ/cm2

15 ft

 

UVC-H & UVC-M Performance Data

 

STEP 5

CALCULATE ESTIMATED EXPOSURE TIME FOR DISINFECTING

  • DETERMINE PLACEMENT OF MOBILE UNIT AND NUMBER OF UNITS TO DISINFECT AREA
  • CALCULATE EXPOSURE TIME = UV INTENSITY (at a specified distance) / UV DOSE / 60 SECONDS
  • UV DOSE = 50 mJ/cm2 

    Screen Shot 2020-05-27 at 1.30.57 PM

 

STEP 6

DISINFECT AREA AND VALIDATE WITH DOSIMETER CARDS

  • Color changes from yellow to orange validates 50 mJ/cm2 delivered​
  • Color changes for orange to pink validates 100 mJ/cm2 delivered
    Dosimeter Cards
  • Exit the room and run disinfection cycle

  • Verify exposure of card and make notations on the card to document the color change

  • Make exposure reading within 24 hours after disinfection 

  • Retain or discard the card in accord with site requirements

  • 1 time use of dosimeter cards

    Screen Shot 2020-05-27 at 1.34.31 PM

 Order UVC Products Here

To learn more about UV disinfection click here

 

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Lisa Proffit

Lisa Proffit

Lisa is the Marketing Manager for XtraLight. She loves well-designed websites and creative content. "You have brains in your head. You have feet in your shoes. You can steer yourself any direction you choose." -Dr. Seuss