Ultraviolet Light

Ultraviolet Light, UV

This term is not new to many but unfortunately, many people are not aware of its benefits and danger of these lights.Depending on the wavelength of the light spectrum, there are 3 different types of UV light.

 

  • UV-A with wavelength of between 315nm to 400nm
  • UV-B with wavelength of between 280nm to 315nm
  • UV-C with wavelength of between 100nm to 280nm

As there are tonnes of information which you are able to find online, we would want to summarise and put it in the simplest way for everyone to understand.

UV lights are part of the sunlight’s spectrum of rays so it has been around since the very beginning. What we get on Earth are mainly UV-A and a little bit of UV-B whereas UV-C is being blocked off by the Earth’s ozone layers from reaching the surface and all living beings.

As you are well aware that exposure to the sun for a period of time will cause sunburns and staring too long at it will disrupt our vision. These effects are only from UV-A and UV-B that penetrates through the ozone layer and hits the Earth surface. This is the reason why UV-C is being blocked off from reaching us which will cause harm and damage to our skin and eyes with more immediate effects.

UV-C is very dangerous due to its characteristic to kill cells by breaking and damaging their DNA structure, preventing them from replicating and reproducing.Because of its anti-microbial and anti-bacteria properties that destroys microbes and pathogens ability to replicate, they are referred to as Germicidal UV. This was discovered more than 200 years ago and was first used to disinfect surfaces in 1877, water in 1910 and air in 1935. 

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“UV-C is by far the most efficient way in killing microbes; bacteria and viruses compared to what we experience sunlight on Earth which is mainly UV-A and a little bit of UV-B”

David Brenner - Director, Center for Radiological Research, Columbia University

However, human exposure to UV-C is very dangerous and may cause skin cancer and blindness to the eyes. We strongly recommend that you take all precautionary measures when using UV germicidal irradiation light for disinfection. Most of the time, it is only used in empty rooms without any organic presence like humans or plants.  

Air Purifier

Air Purifier

Human discovery has invented many preventive and safety equipment. With this ideology, the air purifier was invented to protect us from breathing contaminants and impurities in the air or at least minimize it. From the use of a filter media to trap visible particles, air purifiers have evolved into the usage of HEPA filters to trap very fine particulates which are not visible to the naked human eyes and activated carbon filters to absorb VOC that causes bad smell. These are the 2 main filter media components in any air purifier today.

There are 2 more main components in an air purifier that makes it do what it does best to filter impurities from the air; the design of the device which promotes airflow through its filter and the fan motor it is equipped with. This sounds very simple but without the proper assembly of all these 4 main components, it would just be another redundant electrical device

With these being said, there are also many different ratings in the components used. HEPA filters have ratings where its efficiency and efficacy to filter and trap particulates down to sub-atomic size are tested. The activated carbon filters used are evolving too from charcoal pieces to pleated form activated carbon. Together with its design and fan motor used to complete an air purifier, the end product can be tested in an independent lab to obtain certifications of compliance.

Fresh Air vs Clean Air

Fresh Air vs Clean Air

Unknowingly, there is a difference between fresh air and clean air but both these terms are being used interchangeably to mean the same effect on indoor air quality for the majority. Basically, the main difference would be the level of Oxygen / Carbon Dioxide and fine particles / impurities in the air.

Fresh air is normally felt outdoors. If the surroundings are filled with trees and plants, this is where you feel that the air you breathe in feels so refreshing. Reason being is that the amount of oxygen is far more than carbon dioxide. Green plants use carbon dioxide to produce oxygen through photosynthesis, and that is how you feel fresh air when surrounded by plants. While staying indoors, humans produce carbon dioxide through their normal respiratory process and at the same time reduce the level of oxygen. If there is no air ventilation for the room, this will increase the level of carbon dioxide and reduce oxygen level.

Unlike fresh air, clean air is felt when the air you breathe in does not contain impurities like fine particles, dust, mold and bad smell (Volatile Organic Compound, VOC). It would be impossible for a regular household to achieve a completely clean environment indoors as air flows freely. The best that one can do is to minimize the amount of impurities with the use of an air purifier. Some might feel that by closing the doors and windows from the outdoors will stop impurities from coming into the house but how many of us have no answer to that when there are still dust build-ups even with all the doors and windows closed.