Ultraviolet (UV) light is used to treat water because it effectively destroys microorganisms such as bacteria, viruses, and protozoa, preventing them from reproducing and causing diseases. At the same time, using UV light means no harmful chemicals are needed.
UV light was used for drinking water treatment around the turn of the century. It quickly fell out of favor thanks to the expense and the increasing popularity of chlorination. It is more widely used in Europe, but its use is increasing in the US because of the improvements to UV technology and the safety to humans and the environment.
UV wavelengths
UV radiation occurs at three wavelengths: UV-A, UV-B, and UV-C. Water treatment is accomplished with UV-C light. The US Environmental Protection Agency says UV light with a wavelength of 250 to 270 nanometers is most effective at destroying bacteria, viruses, and protozoa.
To treat water, electricity is discharged through mercury vapor in the lamp, creating UV radiation. The UV radiation then penetrates the cell wall and cell membrane of the microorganisms in the water and damages their genetic material (DNA and RNA). This causes mutations and stops them from replicating. It’s known as photolytic inactivation.
UV light in ultrasonics
Ultra Clean Systems was the first company to add UV light technology to an ultrasonic washer (our Triton series) to make surgical instruments cleaner and safer. The UV light configuration we use is known as a contact type. The lamp is enclosed in a quartz sleeve to reduce the cooling effects of the water.
As the water enters the basin from the facility water system, it flows past the UV light, inactivating any microorganisms present. After flowing over the nonlumen instruments and flushing out the lumen instruments, the water recirculates into the basin. As it recirculates, the water again passes the UV light. Bacteria and viruses dislodged from the instruments are then rendered harmless.
Before recirculating in the Triton basin, the water passes through a filter to remove bioburden dislodged from the surgical instruments. Larger pieces of debris and contaminants can block the light and interfere with the UV radiation.
Protecting staff and patients
We use the germicidal irradiation of UV light in our Triton series ultrasonic cleaners to protect you and your patients. In addition to providing extra cleaning for the instruments by neutralizing the microorganisms in the water, it also reduces the exposure risks for technicians operating the machine.
UV lamps lose effectiveness over time, and should be replaced on a yearly basis. Both of our Triton ultrasonic cleaners count the number of days the UV bulb has been in use, notifying you when it needs to be replaced. The quartz sleeve must be cleaned of mineral buildup, as well, or replaced if it cannot be cleaned. Buildup on the sleeve reduces the intensity of the radiation, reducing its effectiveness.
The UV light installed in the Triton series ultrasonic cleaners