Dosimeter


Deliver Your Desired Dose...Document Your Dosimeter Data

Ultraviolet Dosimeters from American Ultraviolet are safe and efficient tools used to verify UVC exposure for a surface, or an instrument, in healthcare environments, including patient rooms and surgical suites; and in general applications, including food manufacturing and processing facilities, laboratories and clean rooms.

These easy-to-use, playing card sized UVC Dosimeters increase the efficiency of UV light disinfection processes, by knowing when sufficient UVC energy has been delivered to a surface. General purpose dosimeters verify the that the UVC dosage was high enough to reduce the microbial load on packaging materials, food products, and other surfaces targeted for disinfection.

American Ultraviolet Dosimeters also provide you with real-time results that can be recorded, documented, and kept for future verification/validation purposes.

The technology consists of a photo-chromatic ink that changes color when it is stimulated by shortwave UVC radiation (253.7nm)UV Dosimeters from American Ultraviolet, are the perfect complement to any UV light disinfection equipment you use, for any UV light cleaning equipment manufacturer, to disinfect surfaces:

  • Change color at various energy levels, which correlates with a log reduction of microorganism samples (e.g., MRSA, C. diff., E Coli, Salmonella, etc.)
  • Measure specific wavelength of UVC radiation (250-260nm)

How to Use the UVC Dosimeter




Healthcare UVC dosimeter usage protocol

The dosimeters shall be used for every UVC disinfection cycle to get the best and most comprehensive results which is also in line with CDC1 and FDA2 recommendations to quality assure disinfection processes.

Usage of the dosimeters:
1) Place one card at each high touch location you identify or as otherwise directed by site
requirements. The cards can be place in a horizontal or vertical position.
Always make sure the color changing (yellow) area faces toward the UVC device.

2) Exit the room and run the disinfection cycle.

3) Verify exposure of the card and make any additional notations on the card or elsewhere
to document the colour change. Always make exposure reading within 24 hours after
disinfection cycle to get most accurate result.

4) Retain or discard the card in accord with site requirements.
The UVC dosimeter cards are one time use only and should not be used for several
disinfection cycles.


General Protocol UVC dosimeter usage protocol

For food, laboratory, clean room and other non-healthcare applications, the UVC Dosimeter can serve as a placeholder for the object, or surface, that is being exposed to UVC energy. Simply place (or attach by using the adhesive strip on the back of each dosimeter card) a dosimeter in a position as close as possible to the object or surface of concern. If dosage verification is desired on multiple faces of a 3 dimensional object (see below), multiple dosimeters should be used to verify dose to all sides of the targets.

Conveyor Application - attach the dosimeter(s) to a rigid substrate and run it through the conveyor at the speed you would be running the product through in order to determine what kind of intensity you receive.

Chamber application - place the dosimeter(s) where the object that needs to be disinfected would be into the chamber, and run the cycle or exposure time that would be run as if the object was in the disinfection chamber.
 
Handheld application - place or attach the dosimeter(s) in a similar location to where the surface or object that would be exposed to a handheld UVC device would be, and expose the dosimeter as if it was the surface or object.


Note: The UVC Dosimeter is only intended as a visual reference to measure accumulated
UV dose, not to determine level of cleanness.

1https://www.cdc.gov/infectioncontrol/guidelines/disinfection/sterilization/sterilizing-practices.html ,
https://www.cdc.gov/oralhealth/infectioncontrol/faqs/monitoring.html
2 https://www.fda.gov/inspections-compliance-enforcement-and-criminal-investigations/inspection-guides/sterilization-process-controls


1)  How do I use the Dosimeter?
Visit How To Use for usage protocols for Healthcare and General applications.

2) What does a color change mean?
A color change from Yellow to Orange shows that a "UV dose" of 50 mJ has been delivered to the target. A color that continues to change from Orange to Pink shows that a 100 mJ “UV dose” has been delivered to the target. Please refer to the appropriate microorganisms tab above for a list of the most common microorganisms for your application.  

3) How does the dosimeter work?
The dosimeter uses a specially formulated chemistry or ink that is designed to be sensitive to shortwave ultraviolet radiation (UVC - 253.7nm) not visible light or UVA and UVB. When the photo-initiators are subjected to a predetermined level of energy it creates a chemical reaction that leads to a color change, Yellow to Orange.  A higher cumulative dose of energy continues the chemical reaction resulting in a color change of Orange to Pink.

4) Can I reuse the dosimeter?
No, the dosimeter is designed as a single use product. Once it has been used the results should be recorded within 24 hours and the dosimeter should be disposed of properly.

5) Why should we use the dosimeter?
The dosimeter is a valuable tool for all users of UVC technology to save time, money, and as a useful training tool for all disinfection applications.  The dosimeter is designed to provide instant visual confirmation of a successful exposure cycle, help staff to confirm that critical areas and items have received the proper attention, and to provide a record of the level of energy delivered.  

6) Do the dosimeters react to visible light?
No, this improved version of the UVC dosimeter doesn’t react to visible lighting sources like some of the earlier color changing indicators.  However due to their sensitivity to even artificial sources of UV energy we do not recommend exposing the unused dosimeters to visible energy or sunlight. 

7) Can I use the dosimeter with a competitor to American Ultraviolet Company’s equipment?
Absolutely, the dosimeter is activated by exposure to UVC energy regardless of the manufacturer.  Chambers, conveyors, even your “phone soap” box will all register a color change based on the UVC energy levels the dosimeters is exposed to. Some UVC “robots” use on-board sensors to measure reflected energy and set the run time based on the lowest level of energy measured by the machine.  These units can have run times in excess of an hour which extends room turnaround time and prohibits use.  Other units use remote sensors that are arbitrarily placed about the room in an effort to quantify the dose.  The random positioning of these sensors and the potential for them to become the vehicle to transfer microorganisms from one room to another limit use and effectiveness of the UVC device.  The majority of the units available to the market at present use a calculated dose based on the intensity of the UV source and the distance to the target.  While the math works there has not been an easy and economical way to prove the process has truly delivered the necessary level of UVC energy to the target until now.

8) Are there any current studies validating the efficacy of the dosimeters?
Yes, over the last several years prior to releasing the dosimeter to our clients. American Ultraviolet in conjunction with our partner Intellego Technologies has performed several internal as well as independent studies to validate the performance of the dosimeters and there are more ongoing studies being performed. These are available under the “Resources” section of this site and newer ones will be added as they become available.

9) How can a purchase the UVC Dosimeter?
You can purchase the dosimeter in 25 or 50 packs right from this storefront website or by contacting your local American Ultraviolet Sales Manager.