People are increasingly becoming aware that indoor air is very polluted. So much so that even the EPA considers it a thing of concern. Due to poor indoor air quality, one tends to fall ill more often when one stays indoors. This is also referred to as the Sick Building Syndrome. Alas, the COVID-19 pandemic has also made them aware that it is better to stay indoors until people get vaccinated, and things improve. What a dilemma it presents! Nevertheless, the HVAC industry has taken all these aspects in stride and is making increasing efforts to let people know about the revolutionary UV light air purifiers.
A Brief History Of UV Light
UV lights were discovered in 1801, yet they were finally used as germicidal lights for disinfection purposes at least a century later. The credit for this goes to the scientist and physician Niels Ryberg Finsen. He was the first person to use UV light for treating bacterial ailments. Working on the principle that sunlight destroys bacteria, Finsen was successful in developing a UV treatment for skin TB (Tuberculosis). In 1904 he was awarded the Nobel Prize in medicine for this breakthrough treatment.
1. In 1920 France became the first country to deploy a full-scale UV disinfection system for treating water in Marseille. The US followed six years later with UV disinfection for water in Kentucky.
2. Commercially, UV lamps became available in 1930, and their use expanded to air disinfection. Today, UV air purifiers or UV air disinfection units are used in hospitals, care homes, factories, and the hospitality industry.
Are UV Light Air Purifiers Safe?
When it comes to UV lights, safety is a big concern because exposure to UV light can result in skin diseases and sometimes even cancer. There are many who say you should not use UV light air purifiers indoors. Yes, exposure to UV lights is dangerous. There is no doubt about that. However, the good news is that you have the option of installing fixed air purification systems. These fixed UV light air purifiers are installed either inside the ducts or facing the evaporator coil of the HVAC system. Hence, there is no way you or anyone in your house or building can come in contact with it.
Which Part Of UV Light Spectrum Is Used In UV Light Air Purifiers?
Ultraviolet light is made up of three spectrums, namely – UV-A (315 to 400 nanometers), UV-B (280 to 315 nanometers), and UV-C (100 to 280 nanometers). UV light air purifiers use only the UV-C spectrum. It is because the frequency of light in this spectrum is mainly responsible for the disinfectant or purification activity, precisely what the air purifier requires.
Exposure to UV-C light damages the DNA of microorganisms, which triggers a self-destruct mechanism in them. Since bacteria are single-cell organisms, damaging their DNA renders them sterile and kills them.
How UV Light Air Purifiers Work
UV light air purifiers are generally installed to complement the working of the pre-installed heating and cooling system. This ensures all the air inside the home or building is free of germs. Typically, it consists of a chamber with lamps that emit UV-C light and is placed downstream of the air filter. The UV air purifier unit is set up inside the return duct or facing the evaporator coil. Indoor air that falls in the path of the UV light gets disinfected with an exposure of just a few seconds.
A Few Facts About UV Lamps
Here are a few facts about UV lamps that will answer many of the questions that pop into your mind.
1. UV lamps do not make any noise. They are silent in operation.
2. UV lamps don’t have any odor. So when they are on and working, you will not sense any different smell.
3. Depending on the casing that surrounds the UV lamp, you may not be able to see any glow from the bulbs either.
4. UV bulbs are extremely low maintenance and need to be changed annually.
5. Exposure to UV light from 6 seconds to a minute is enough to kill infected particles.
Effectiveness Of UV Air Purifiers
UV-C light is a proven and widely used method of disinfection. But it cannot disinfect the surfaces inside the home. For that, you will need a portable air purifier, but they are more of a trap for dust mites and mold allergens.
There are several factors affecting the effectiveness of UV-C light. These are:
1. Whether the contaminants are falling in the path of the UV light
2. Whether the light is being impeded by the airflow’s cooling effect.
3. The material of the bulb producing the UV light
4. Whether the UV-C light is of the required dosage.
5. The length of time the pollutant is exposed to UV light.
6. VOCs or Volatile Organic Compounds are unaffected by UV light.
7. UV light cannot altogether remove pet dander, dust, cigarette smoke, or mold.
8. UV light potentially deactivates bacteria with sufficient exposure.
Food For Thought
If the UV air purifier produces ozone, it is a risk to your health and that of the other occupants of the building as well. If there is no threat of ozone, UV light purifiers present some type of sterilization capability. These should still be used together with filters to trap particles. If you are expecting 100% results, you might be disappointed. Nonetheless, continuous advancements are being made each day, and sometime in the near future, you may have a product that excels in air disinfection.
If you are a resident of West Palm Beach, Florida, and wish to explore further the options for improving indoor air quality, contact the air experts at Aztil Air Conditioning. We are a family-owned HVAC business, successfully operating in South Florida since 1981. Our 100+ strong team of technicians is well equipped to handle all your queries and concerns. Additionally, you can also engage our services for HVAC installation, repairs, and maintenance. To book an appointment or simply talk to us, call +1-888-729-8452. We are looking forward to serving you with our world-class and affordable HVAC services.