UVC Germicidal Fixture FAQs

Why would I install UV in my furnace at home?

The use of UV-C in your home Heating, Ventilation and Air Conditioning (HVAC) system reduces the biofilms on the coil and keeps mold and bacteria out of the drain pan. This does several beneficial things:

   > Keeps unwanted microorganisms from spreading in your home

   > Allows it to be more thermally efficient in transferring heat to cool or heat your home - saving you energy

   > Prevents the blower from working too hard to push air through a partially clogged coil – extending your system life and reducing potential repairs


What size unit do I require?

Looking at the size of filter your furnace uses will generally give you a good indication of the maximum size of UV-C lamp your HVAC system can accommodate at the coil.  Many newer homes can accommodate a 20” lamp with no problem. If your system takes 20x25 or 20x24 filters, you are good to go with a 20” UV-C lamp system.


Some older homes, and some homes that have multiple, smaller HVAC systems for multi-zone setups, will require the smaller 14” UV-C lamp size.


How much electricity is required?

Most American Ultraviolet UV lights operate on 120V/60Hz and draw <5 amps. Please consult individual product pages for more specific information on a particular product.


How long does a UV lamp last?

This can vary widely based on the quality of UVC lamp and how the germicidal lamp is being used. Though many companies offer lamps that last 12 months, American Ultraviolet provides lamps that should be replaced every two years.


It’s been more than 24 months and I can see the lamp still emitting a blue glow; is it still good?

Germicidal UV-C lamps will typically emit a blueish glow long after the recommended lamp change timeframe, but they are not producing enough UVC to be effective and need to be changed at the recommended intervals for optimal performance.


What is the size of a water purifier for residential applications?

This depends on whether you are treating all the water entering the home at the Point of Entry (POE), or if you are treating the water exiting individual faucets – like your kitchen sink – at the Point of Use (POU).


   > Whole house POE applications are generally handled with a 10 gallon-per-minute , AQ-10 (GPM) system.

   > “Under Cabinet” POU applications can be handled with a 2 gallon per minute  , AQ-2 (GPM) system as most faucets’ flow does not exceed 2GPM.


What does an in-line water system do?

An in-line UVC water purifier will reduce the harmful bacteria and viruses that can be found in residential drinking water. UVC systems eliminate 99.9% of unwanted microorganisms for the water. A UV-C water disinfection system will not change the color or flavor of your water.


Where’s the best place to install a whole-home POE inline UV-C water treatment system?

UV-C energy is most effective in the cleanest, clearest water, so the cleaner the water going in, the more effective the UV-C system is at reducing the microbial content of the water.  Simply put, the UV water system should be the final step before the water goes to use within the house – after any filters, water softeners and Reverse Osmosis systems.


Why would I use a BLADE Handheld UV-C unit?

The Blade unit is a lightweight UV-C device designed to reduce microbial load (bacteria, viruses) on non-porous surfaces, such as your countertop, mobile phone, computer keyboard, and TV remote.


How long does it take to reduce microorganisms on surfaces?

UV-C disinfection works via time and intensity; the closer you have the device to the surface, the shorter the disinfection time. Most household applications require less than 5 seconds when ≤ 2 inches away from the surface.

UVC Dosimeter FAQs

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


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. 


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.


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.


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. 


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. 


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.


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.


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.