LED AC UV Light Kit

Before answering this question, let’s first understand how the air conditioner works:

In the impression of many people, the split air conditioner in the home can be cooled because the outdoor unit of the air conditioner sucks in the air outside the room, and then cools it into the cold air and sends it back indoors.

But this is not the case. Although the indoor unit and outdoor unit of the air conditioner have a connection, what is exchanged in the pipe is not air, but only heat. The reason why the indoor unit can reduce the temperature in the room is because it reduces the temperature in the room through the suction port The air is sucked in, and then this part of the air is cooled by the evaporator, and then sent back to the room through the air outlet.

In the constant internal circulation, the room is filled with air-conditioning.

But in this way, the germs and bacteria hiding in the corners of the room will also gather inside the air conditioner along with the wind, and the temperature and humidity inside the air conditioner are very suitable for the growth and reproduction of microorganisms, so the air conditioner necessary in summer is easy It has become a concentrated place for germs and bacteria.

Therefore, we use UVC LED air purification lamps to set up a line of defense in the internal circulation mechanism of "air intake-cold air-supply air":

When the microorganisms in the air enter the inside of the air conditioner, they will first pass through the UVC LED air purification system's photo-contact membrane filter. At this time, its UVA will start to work to activate the photocatalyst and decompose these microorganisms into CO2 and H2O.

After the microorganisms are "washed" by the light-touch membrane filter, they will also be irradiated by UVC, destroying their RNA or DNA. In this way, when the air is sent back to the room, along with the bacteria that they enter, Has been wiped out.

This is the principle of double disinfection and sterilization of LEDHOME's UVC LED air purification system.

In October 2020, our latest version of the test data report of Guangzhou CAS Testing Institute has been released, and this test report is internationally certified.

In this test, we carried the entire air conditioner into the laboratory, simulated a confined space the same as the indoor environment, put a certain amount of germs, and then waited 30 minutes and two hours after the air conditioner was turned on before testing the concentration of bacteria.

The experimental results show that the bacteria killing rate in 30 minutes is 80%, and the bacteria killing rate in 2 hours is 99.9% (it is estimated that it can reach 99.9% in 1 hour, but we did not test it for 1 hour).

This means that for users, as long as they are turned on for 30 to 60 minutes, the concentration of bacteria and viruses in the environment can basically be reduced to a very low level.

Of course, some customers may want more intuitive feedback on the air purification effect. You can smoke a cigarette (or light a cigarette) indoors while the system is running. After a while, the smell of smoke will dissipate and you can also directly feel the purification effect of the system at the olfactory level.

Simply put, a photocatalyst is a process by which a certain medium decomposes bacteria and germs into CO2 and H2O under the action of light, and this medium is called TiO2.

TiO2, the name sounds very strange, in fact, it is an "old friend" in our lives. Whether it is the sunscreen commonly used in summer, the paint on the wall at home, or the white color in candy, TiO2 is an important component.

So, why do we need to add UVA+ photocatalyst when the UVC LED air purification system has UVC antivirus?

The reason is that the light intensity of UVA is ten times that of UVC. Although it does not have much sterilizing effect, it is the best trigger medium for photocatalyst.

Under the trigger of UVA, the efficiency of photocatalyst is 1550 times that of UVC. That is to say, photocatalyst is used as the first sterilization and disinfection process. When used in combination with UVA, it can effectively decompose microorganisms into CO2 and H2O, and then Leave it to UVC for disinfection, which can maximize its disinfection and sterilization effect.

In fact, this is a problem that you don't need to worry about at all.

According to the carcinogenic risk to humans, the IARC (International Agency for Research on Cancer) under the World Health Organization divides the chemicals that have carcinogenic risks to humans into 4 categories:

Category 1: It is carcinogenic to humans, with clear carcinogenicity.

Category 2A: It is likely to cause cancer to humans. There is sufficient evidence to prove carcinogenicity to laboratory animals but limited evidence of carcinogenicity to humans.

Category 2B: It may cause cancer to humans. There is insufficient evidence to prove that it is carcinogenic to laboratory animals. There is insufficient evidence of carcinogenicity to humans.

Category 3: The carcinogenicity to humans is not yet classified, and the possibility of carcinogenicity to humans is low.

Category 4: It is unlikely to cause cancer to humans. Among them, the so-called 2A category includes "intake of red meat" (pork, lamb, beef), "shift work involving circadian rhythm disruption" (simply speaking, staying up late);

In addition to "TiO2", the same category 2B also includes "coffee" that everyone drinks daily.

From this perspective, aren’t we “carcinogenic” every day?

And in fact, it is not TiO2 itself that may cause cancer, but because of its "thin body."

Regardless of whether it is TiO2 or not, as long as humans are exposed to high-concentration (for example, 10mg/m3) of insoluble tiny particles for a long time, these tiny particles may indeed cause related diseases after being inhaled into the lungs for a long time.

However, even those who are engaged in the production of TiO2, the concentration of TiO2 they can access is generally only between 0.3mg/m3-6mg/m3, let alone ordinary consumers?

What's more, when TiO2 is processed, especially the nano-sized TiO2 used in LEDHOME's air purification system, it is firmly embedded in the molecular gap of the carrier (such as air conditioning filter), and it can't be washed off. How can it be possible? How about going through the trachea to the human lungs?

UVA with a wavelength of 320～400mm has no effect of sterilization and disinfection. Its main application scenarios are generally curing, printing, currency checking, nail art, etc.

(However, if UVA is used to excite the photocatalyst but it is the best catalyst, its excitation efficiency is about 5 times that of the same radiant flux UVC, let alone at the same cost, the radiant flux of UVA is almost 1000 times that of UVA )

UVB with a wavelength of 280-320nm has no effect of sterilization and disinfection, and its main application scenarios are generally health care and treatment of skin diseases. Only UVC with a wavelength of 100-280nm has the effect of sterilization.

(But in fact, the description of "sterilization and disinfection" is not very accurate, because its working principle is actually to destroy the DNA or RNA of the cell, so that it no longer has the function of reproduction, and the lifespan of a single bacteria/virus is often very short. , So it often means death).

The reason why LEDHOME's air purification system uses UVC+UVA+photocatalyst to kill is because ultraviolet rays are not a sniper rifle that can headshot with one shot. It is more like a submachine gun that needs to be shot many times to kill the enemy. Viruses are not the underdogs that can kill with one move, they have a health bar.

Therefore, if bacteria and viruses are still in the air, it takes time to shoot them with ultraviolet rays, not to mention that they flow at a high speed, then it takes time to shoot them.

Therefore, we added UVA+ photocatalyst to make them decomposed into CO2 and H2O through the action of photocatalyst before being scanned, ensuring that our UVC LED air purification system can efficiently kill them.

In short, LEDHOME's air purification system turns the split air conditioner into an "advanced air purifier". Compared with the traditional air purifier, its "advanced" is reflected in the price. Most of the traditional air purifiers cost several hundred dollars, but the price of LEDHOME's Ultra Air is less than half of the traditional air purifier.

Regarding the size, LEDHOME's Ultra Air is installed inside the air conditioner. Even if the package is unpacked, the floor space is only the size of A4 paper, which does not occupy any family space. However, traditional air purifiers are often too large for small It is not very convenient for the users of the household type.

Regarding functions, traditional air purifiers can’t eliminate bacteria and germs. It just adsorbs these microbial corps on the filter and temporarily “shuts them off” the harmful elements. LEDHOME’s Ultra Air uses UVC photocatalyst UVA, Through the elimination of the army of microorganisms inside the air conditioner, "the dead bodies of bacteria" will not remain on the filter.

Therefore, compared with air purifiers, LEDHOME's Ultra Air are cheaper and more effective.

First, let's take a look at the internal structure of LEDHOME's UVC LED Strip: it is composed of 2 PCS UVC LEDs and 8 PCS UVA LEDs.

Although UVC is harmful to the human body by direct irradiation, its energy weakening is extremely strong. At a distance of one meter from UVC LEDs, its energy weakening can reach 90%, that is to say, 100mW of UVC light can irradiate one meter. Outside, its energy is only 10mW.

Moreover, UVC has very poor penetration. Except for a few materials such as quartz glass, which can penetrate, if it is irradiated on a wall or plastic material, it will be directly absorbed, and only a few materials such as aluminum can refract the light.

LEDHOME’s UVC LED Strip is installed on the front panel of the air conditioner. The light emitted during operation will only illuminate in two directions. If it illuminates the filter membrane downwards, there will be no “leakage”. If a small amount of upward light spills onto the wall, the light will be directly absorbed.

We also assume that it can really refract, but the distance between our location and the distance of the air conditioner is at least 2 meters away, and the light is strong. In other words, if we stand 1 meter away, it irradiated energy is 10mW, but if the space we are in is 25 square meters, then the energy is equally divided into every CM space, and the energy is almost close to zero.

And only when the light intensity of UVC reaches 5μW/cm2, it will be harmful to human body, so there is no need to worry about UVC light leakage.

As for UVA, our ultraviolet home uses 405nm UVA. According to the IEC62471 photobiological safety test standard, 405nm UVA belongs to the "exempt level" and is light that does not cause harm to the human body. In summary, the operation of LEDHOME's UVC LED air purification system is very safe.

According to the characteristics of the LED chip: ultraviolet rays will continue to degrade the chip material of the organic package, and the LED chip is very sensitive to O2 and H2O.

Therefore, we will use inorganic packaging materials that will not be degraded by ultraviolet rays to assemble the chips, and before the LEDs leave the factory, the H2O and O2 in the LEDs are vacuumed out, so as to ensure the life of the UVC LED. Reach 10,000 hours.

If organic packaging materials are used and no vacuum process is used to process the LEDs, the actual life span may only be 1000 hours, or even 300-500 hours.

Regarding this issue, we first look at two data: According to the IEC62471 standard, the UVC radiation illuminance must be below 0.2μW/cm2 to ensure the safety of long-term exposure, and the irradiance of short-term exposure to UVC radiation cannot exceed 1.7μW/cm2.

So, what is the data of our products? According to calculations, when a single light source is 10mW, if the distance exceeds 18 cm, the radiation intensity of the light source will be less than or equal to 1.66μW/cm2, reaching the level of short-term contact; but if it exceeds 52 cm, the radiation intensity of the light source will be less than or equal to 0.2μW/cm2, ensuring long-term exposure safety.

Of course, since the product has a 2PCS 10mW UVC LED, there will be intensity crossovers in some cases; therefore, for conservative consideration, we will consider it as a 20mW light source for calculation.

Once the distance exceeds 26 cm, the radiation intensity of the light source will be less than or equal to 1.6μW/cm2, reaching the level of short-term contact; but if it exceeds 73 cm, the radiation intensity of the light source will be less than or equal to 0.2μW/cm2, ensuring long-term exposure Safety.

From this point of view, as long as you are not looking at the light source, you don’t need to worry too much about an accidental behavior.

Of course, in any case, we do not recommend that users turn on the front panel of the air conditioner when the lights are on, because it is difficult for non-professionals to grasp the safe distance and time of exposure.

In fact, this is why we choose the air conditioner as the carrier of disinfection and sterilization, and the design installation location is the back of the air conditioner front panel and the top of the inlet grille:

① Its installation height prevents children from touching it (like the ultraviolet mercury lamp placed in the room is really very dangerous. After reading several news, it is children who find the ultraviolet mercury lamp from the storage box and play with it. )

② Its installation position determines that there is no possibility of UVC leakage, because almost all UVC in the air conditioner cavity/top wall of the air conditioner will be absorbed, and there will be no reflection (because the penetration of UVC and the reflectivity on common materials are very weak).

Because the dose of ultraviolet light to kill Staphylococcus is quite high, 36.9mJ/cm2, which is 3.42 times that of E. coli commonly measured in the market, which also means that the energy required to kill Staphylococcus albicans is much higher than that of E. coli.

and so:

① We can kill "high-grade bacteria" such as staphylococcus, and naturally these "low-grade bacteria" such as E. coli.

② If we kill Staphylococcus for 30 minutes, other bacteria with lower dose requirements will only take a shorter time. When you or customers compare the efficiency of disinfection and sterilization, in addition to looking at the final figure, we also need to compare the species of bacteria.

Sometimes customers will ask how much the impact on the air volume will be after adding the filter membrane. Today we tested it and the wind speed with the filter membrane is 2.7-2.8m/s, and the wind speed without the filter membrane is 3.1- 3.2m/s, the impact is about 10%-15%.