For removing formaldehyde in decoration, green radish, activated carbon and grapefruit peel are not as good as it!

Many of my friends who bought new houses chose to renovate them in April and May, just in time for summer to get rid of the odor. After all, indoor air pollution has always been a lingering haze in the minds of every decorator. Today we will talk about what indoor air pollution is and what methods are reliable for dealing with formaldehyde?

#1What are the main types of pollution?

Generally speaking, indoor air monitoring tests five items: benzene, TVOC, formaldehyde, ammonia, and air radon.

TVOC is the sum of volatile organic compounds, the main ones of which are toluene and o-, m- and p-xylene. Benzene is also a volatile organic compound, but it is so destructive to humans that it has been set up as a separate school to deal with it alone.

Benzene and TVOC usually go together and often appear in paint. However, although benzene and its derivatives are very powerful, they also evaporate quickly. As long as you don't live in a high-concentration environment and open windows for ventilation, they can be quickly eliminated.

Image source: Pixabay

Ammonia is a colorless gas with a strong pungent odor. As long as the owner of the house does not have the habit of constantly urinating and defecating anywhere, it will generally not exceed the standard. (What a cold joke!)

The main source of ammonia pollution is the concrete of buildings, but firstly, the standards for concrete are very strict and it is unlikely that the standards will be exceeded; secondly, other issues are all about horror stories of people being trapped in walls, so it is better not to say more about them. Anyway, if there is really a problem with the concrete of the building, it will not pass the construction inspection.

Air radon is colorless and odorless, similar to ammonia, so there is generally no need to worry. Before a house is built, the soil radon test will be carried out. If the soil radon exceeds the standard, a certain isolation treatment will be done before construction. Therefore, as long as the homeowner does not prefer natural stone when decorating, and uses artificial stone for window sills, kitchens, and worktops, there will be no problem with air radon.

Of course, if it is really found that the standard is exceeded, then don't have any fluke mentality, and quickly remove the source of pollution and hand it over to the relevant department for disposal. This kind of thing can only be isolated or returned to nature.

Well, let's leave formaldehyde, which is the most familiar to everyone. The main source of formaldehyde is artificial adhesives. Plywood, particleboard, density board, these boards are all formed by adhesives. In addition, wallpaper glue is also one of the important sources of formaldehyde pollution in interior decoration.

At the same time, because formaldehyde is much more stable than benzene and its derivatives, it has become the most troublesome of the five indoor decoration pollution items.
What to do then?

#2 Battle with formaldehyde

01Green plants that are said to absorb formaldehyde

There are always a lot of green plants that are mentioned together with "absorb formaldehyde", such as green radish, spider plant, monstera, cactus, aloe vera, and so on. In this endless list of plants, some plants do have a certain absorption effect on formaldehyde, but the absorption effect, whether there will be pollution release again, and other issues are too complicated to be generalized.

Based on my years of work experience, because formaldehyde can damage the wax layer on the leaves of green plants, the mortality rate of green plants will also increase. In addition, green plants will also have a certain biological resistance to pollutants, so after absorbing a certain amount of formaldehyde, they will begin to refuse to absorb less and less. In other words, the higher the pollution concentration, the lower the green plant's ability to absorb formaldehyde.

The best way to use green plants is to purify the beautiful air in a room that does not exceed the standard, rather than letting them gasp and do the cleaning work that they are not good at in a heavily polluted room.
Out of the principle of cherishing life, in a room with a high formaldehyde concentration, in order to ensure the normal breathing of plants, please first choose "open windows for ventilation".

02Formaldehyde sealant

This is a relatively advanced material sealing technology. As the name suggests, this new material can seal formaldehyde from pollution sources such as boards and wallpapers inside the material to inhibit the volatilization of formaldehyde.

However, formaldehyde sealants will not cause any chemical changes to the pollution source, that is, the amount of formaldehyde waiting to evaporate will remain there, and it is just a temporary closed space. Secondly, it is difficult for people without professional training to completely seal all indoor pollution sources. As long as there are omissions, it is almost futile. Thirdly, the quality of formaldehyde sealants on the market varies. If you are unlucky enough to use inferior products, it is very likely that you will not only fail to prevent the crazy evaporation of formaldehyde, but also cause secondary pollution.

Therefore, if you really want to take this approach, then you should find a professional company with a good reputation to do it for you. In addition, since formaldehyde sealants only treat the symptoms but not the root cause, after the company helps to deal with it, for the sake of safety, please first choose "open the window for ventilation".

03Photocatalyst

Photocatalyst is a general term for optical semiconductor materials with photocatalytic function, represented by nano-scale titanium dioxide. It is coated on the surface of the substrate and produces strong catalytic degradation function under the action of light.

Using photocatalysts is a method of removing formaldehyde that can treat both the symptoms and the root cause. Photocatalysts work on the formaldehyde in the pollution source itself, promoting the activation of pollutants and accelerating the decomposition rate, without giving them a chance to emerge and harm the air. It can be said that the effect of photocatalysts is relatively good when used correctly.

But similar to formaldehyde sealant, it is also not something that can be done by an individual. You need to find a professional company, the price is quite expensive, and it may cause furniture and walls to discolor. If all these are taken into consideration, it is better to try "opening the window for ventilation" first to see how the effect is.

04Activated carbon

The adsorption capacity of activated carbon for formaldehyde is worthy of recognition, and there are still many detailed parameters that need to be paid attention to. For example, what kind of activated carbon is the most effective, and whether the finer (larger mesh) activated carbon has a better adsorption effect.

Image source: Pixabay

There is always a rule in the market: once something appears everywhere, it is inevitable that the quality will vary.

The author does not intend to point out which products are taking advantage of the situation. It is just that if you want to activate activated carbon, it is not just drying it in the sun or throwing it in the microwave for a few turns. The commonly used physical activation method requires the activated carbon to be placed in a high temperature environment of 100℃ for 24 hours. If the activated carbon is not activated, it can basically be said to be ineffective. It is impossible to tell whether the activated carbon is activated or not, so you can only try to buy activated carbon in sealed packages.

In addition, many people have a misunderstanding that since I use activated carbon, I have to close the doors and windows to let the activated carbon brothers absorb it happily. Unfortunately, the amount of activated carbon (activated) piled up by ordinary people is not more effective in reducing the concentration of formaldehyde in indoor air than opening windows for ventilation. Therefore, when you have bought a large amount of activated carbon and brought it home to absorb formaldehyde in the house, in order to extend the service life of the activated carbon, please first choose "open windows for ventilation".

05Grapefruit peel, white vinegar, onion

These are completely useless. At most, they can irritate people with their own strange smell, making people not notice the stimulation of colorless and odorless formaldehyde. Therefore, if the formaldehyde concentration in the house is not only excessive, but also there are so many messy things, quickly "open the window for ventilation"!

To sum up, each method has its own advantages and disadvantages, and opening windows for ventilation is the only unchanging principle.

Source: Chongqing Science and Technology Museum

Author: Fei Xue, a frontline fighter in an air quality monitoring unit

Review experts: Huang He, Li Chunli, Chen Tao, Xu Xiaoping

Statement: Except for original content and special notes, some pictures are from the Internet. They are not for commercial purposes and are only used as popular science materials. The copyright belongs to the original authors. If there is any infringement, please contact us to delete them.