Research: Unity of Knowledge and Action
Living in a new house, with formaldehyde, flustered ...
What is the relationship between natural original sin formaldehyde and terrible leukemia and cancer?
A little knowledge of formaldehyde will inevitably cause unknown panic.
How did formaldehyde come from? How to control it? ……
In view of the fact that the understanding of formaldehyde in most online articles is not comprehensive and rigorous, even misleading and underestimating, a bunch of high-powered technical terms confuse the audience, and from time to time, uncommon and boring knowledge points appear to hit the IQ of liberal arts students, and boring explanations are like chewing wax and drinking boiling water.
The combination of knowing and doing design team consulted and studied a large number of documents, authoritative files, historical documentaries and other materials, and visited factories and building materials markets for in-depth research. Combined with many years of design and material selection experience and professional experience, a panoramic and thorough analysis of formaldehyde was carried out.
(Research photos of the design team of knowing and doing in one)
In nature, the metabolic degradation of trees, animals and microorganisms will produce trace amounts of formaldehyde. Formaldehyde is actually a natural existence on the earth and an ancient organic matter. It has never been discovered by humans before. Some fruits and vegetables, such as apples and cabbages, contain trace amounts of formaldehyde, but they will be decomposed by the human metabolic system after eating.
(Photo taken by Zhixing Design Team in Florence, Italy)
It was not until 1859 that Russian scientist Boutleroff first presented a theoretical report and discovered formaldehyde.
(Source: CCTV- 10 Discovery Channel)
1869, German chemist William von Hoffman confirmed through experiments that formaldehyde can be extracted from the chemical reaction of methanol.
Yes, the professor with the same beard as the headmaster of the Harry Potter School of Magic looks like Gandalf, the wizard of The Lord of the Rings. He took off his hat.
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(Source baike.baidu.com)
1959, the first formaldehyde production plant developed by London chemical company Formox in pouch, Sweden was put into operation.
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(Source Formox official website)
Major manufacturers have followed suit, joined the army of manufacturing formaldehyde, and started the road of commercialization. Formaldehyde is widely used and plays an important role in industry. As a chemical product with low acquisition cost, it has become one of the most important industrial basic raw materials in the world, and officially opened the prelude to infiltrating human life. Humans have entered the era of formaldehyde, and formaldehyde has been continuously applied in the fields of adhesives, plastics, medicine, textiles, sterilization and so on. Furniture, cars, paints and fabrics that we are familiar with in life all have their own figures. Before its toxicity was concerned, it was the darling of industrial society and had many practical values to use. The hand of industry wields this double-edged sword, which brings good news to the commodity manufacturing industry, but also spreads branches and leaves in the aspect of toxicity, and goes to the road of demonization.
(Source: 5 1sole.com)
Formaldehyde will destroy the internal structure of protein and make it lose its biological activity. This property is usually used for antisepsis and sterilization, which can inhibit the reproduction of parasitic microorganisms. Formaldehyde is easily soluble in water. It contains 35%~40% aqueous formaldehyde solution, which is medically called formalin. It can be used to make animal specimens, soak and preserve human anatomical organs, and can also be used to prevent insects from eating and disinfect natural wood. Seafood and aquatic products soaked in formaldehyde solution can keep the surface bright and beautiful.
(Source sohu.com)
Let's take a look at how formaldehyde "invades" the household industry.
Due to excessive logging, the earth's environment has been destroyed, and the supply of natural materials such as natural wood, animal leather and plant fiber can't meet the growing demand of human beings, resulting in the shortage of original ecological material resources. Therefore, human beings have developed various synthetic materials as substitutes, which have various styles and cost advantages and are quickly favored by the home market. Formaldehyde plays an important role in the production of artificial materials. Taking wood-based panel as an example, the adhesive containing formaldehyde is an indispensable part in its manufacturing process.
(Source edushi.com)
Formaldehyde can be combined with many chemical products to give birth to new industrial raw materials, such as melamine resin, a derivative member of the "formaldehyde" family, which can be used in plastics, coatings and other production fields.
When formaldehyde meets urea, it can jointly create "urea-formaldehyde resin", which is a simple and rude name in the industry, practical and easy to remember. It is a very high-profile member of the formaldehyde family. Is it wood-based panel? The variety with the largest amount of adhesive is very cheap and has sufficient capacity. Beat other substitute formaldehyde-free high-priced materials in the price competition, meet the huge demand of the mass market, and be welcomed by the majority of manufacturers.
(Source woodmaket.com)
In the production and processing of wood-based panels, wood blocks, scraps and particles. Bonding and splicing with urea-formaldehyde resin. After multi-layer pressing by machine tool, the cured and dried adhesive in the molded plate is unstable, and there are problems such as poor water resistance, poor viscosity and easy shrinkage. It will happen. The formaldehyde trapped inside will escape like a seal and transfer to the position where the plate is easy to volatilize formaldehyde, and the other part of the formaldehyde that does not participate in the compression activities of the machine tool will also escape in the gas state.
Although MDI eco-adhesive without formaldehyde has been developed as a substitute for raw materials such as urea-formaldehyde resin (this material reacts with straw fiber to form a stable polymer structure, which is relatively safer), it is still difficult to popularize the market because of its high price. At present, adhesives such as urea-formaldehyde resin still firmly occupy the mainstream position of artificial adhesives.
(Source qiyeku.com)
The industrial value of formaldehyde has always been exploited and utilized by human beings: "Where there is a need, I will go!" In the textile fabric industry, the addition of formaldehyde additives can make clothes and curtains wrinkle-resistant, enhance the sense of softness and straightness, and prevent fading. They should feel good and have a good face value, as well as mattresses, bedding, sofa fabrics, carpets and so on. The addition of formaldehyde helps their commercial needs.
(Research photos of the design team of knowing and doing in one)
The boiling point of formaldehyde is very low,-19.5 degrees Celsius, and it is easy to volatilize and diffuse into the air.
With the increase of temperature, it is released for the second time, colorless, transparent and irritating.
Formaldehyde generally exists in three states indoors:
(1), free state: floating and diffusing in the air as a gas, drifting with the air.
(2), adsorption state: attached to the surface of the object, if the object is compared to the moon, formaldehyde particles like a spaceship landed on the surface of the moon.
(3), combined state: mixed with other things into liquid or solid, such as block high-density board, multi-layer plywood, hidden deep enough.
No matter what the state, as long as it threatens human health, the motivation is abnormal.
Formaldehyde has been listed as a first-class carcinogen of IARC by the World Health Organization. In order to prevent the formaldehyde emission of man-made materials from exceeding the standard, various countries have formulated different levels of environmental protection standards.
At present, the common environmental protection standards are: national standard E 1, E0 (non-national standard), European standard E 1, E2, American standard CARB, Japanese standard F-star, etc. Before defining the difference between these standards, let's first understand the detection method of formaldehyde emission:
Generally, there are perforation extraction method, dryer method and climate box method.
The principle of extraction method is to soak the plate sample in toluene solvent to separate formaldehyde, then dissolve it in water to get the extract, and finally measure the formaldehyde concentration in the liquid.
(Source firmly.com.cn)
The principle of the dryer method is that the flat sample is sealed in a dry glass container and hung overhead, and the released formaldehyde is directly absorbed by distilled water at the bottom of the container, and then the formaldehyde concentration in the water is measured by an instrument.
(Source b2b.hc360.com)
The above two methods are usually used to control the production quality of enterprise products.
Climate box method refers to adjusting the temperature, humidity, wind speed and air exchange times in the box, simulating the environmental state in people's daily life, putting the board samples into the box, letting the formaldehyde in the board release naturally, detecting the concentration of formaldehyde in the air in the box, and calculating the test results with software.
(Source goepe.com)
CARB standard in the United States is an environmental protection standard formulated by California Air Resources Board, and it is one of the most stringent standards for formaldehyde emission. Using the climate box method to detect samples not only strictly limits the formaldehyde emission of wood-based panels, but also monitors the production process of the factory, and records the process, sales and transportation to ensure that every batch of boards in the factory is qualified products.
According to the environmental protection level from low to high, it is divided into:
Carbohydrate phase 1(≤0.05ppm)
PPM is the unit of concentration, which is the abbreviation of parts per million, that is, the ratio of parts per million.
Carbohydrate stage 2(≤0.05ppm)
The limit value is the same, but the detection method is more strict than P 1.
ULEF (full name: ultra-low formaldehyde emission)
Ultralow formaldehyde emission
NAF (full name without added formaldehyde)
The most stringent formaldehyde-free inspection-free certification does not contain formaldehyde.
Japan's F-star standard originated from the agricultural standard law promulgated by Japanese authorities (JAS law for short, short for Japanese agricultural standard). Divide the environmental protection grade by the number of stars after the letter F, and the plate with F-star grade can be obtained. First of all, the factory must pass JIS (abbreviation of Japanese industrial standard). Be careful not to be confused with JAS above. Letters between JAS and JIS are different. ) It needs to be audited and certified by industry standards, and all aspects of raw materials, production processes and finished products should be followed up regularly. After the factory certification, JAS products are eligible for F-star certification. Although the dryer method is used for testing, the supervision and control of formaldehyde limit is very strict. The environmental protection grade of F-star is divided into:
F ★★★★ (≤ 0.3mg/L)
F★★★ (≤ 0.5mg/L)
F★★★ (≤1.5mg/L)
F★(≤5.0 mg/L)
European standards E 1 and E2 were originally the evaluation grades of Germany, and later became the common standards for CE certification in EU countries. The limit value of E 1 ppm (which can also be converted into 0. 124mg/m3) is more environmentally friendly than E2, and exceeds the limit value. Eurostandard is the most famous environmental protection in the domestic market at present.
The national standard is based on the determination of the environmental protection level of "samples for inspection", and the evaluation factory is another independent third-party quality certification system, such as ISO, 3C, CNCA, OHSMS, etc. Since 20 17, the General Administration of Quality Supervision, Inspection and Quarantine and the National Standards Committee have revised and issued the "Formaldehyde Emission Limit of Wood-based Panels and Products for Interior Decoration Materials" (GB 18580-20 17) (hereinafter referred to as the new standard).
The new standard E 1 has stricter requirements for formaldehyde emission than before, with a limit of 0. 1.24 mg/m3, which has begun to be in line with international standards. The unit of mg/m3 describes the total weight of formaldehyde gas contained in three-dimensional space. M3 (cubic meter) measures the size of space, and mg (milligram) represents the weight of matter, which can be used to measure the weight of a sesame, an ant and a hair. The weight of a grain of rice is about 4.3 mg, and the total volume of three washing machines with normal specifications is about 1 m3. You can compare the weight of a grain of rice with the volume of three washing machines by yourself, and imagine the concept of 0. 124mg/m3.
The new national standard E 1 is a health "safety standard line" enforced by the state, which was officially implemented from May 20 18 to May 1 year, with the limited mark E 1. The new standard revised the test method of formaldehyde detection and its formaldehyde emission limit value, canceled the E2 level of the old national standard, and canceled the detection methods of perforated extraction method and dryer method, and unified them into "1 m3 climate box method", which was stipulated as the arbitration method in the national standard GB 18580-20 17.
Why is there no E0 level? What is the E0 level on the market?
This should be related to the formulation of the old national standard. In 2007, only the standard of laminate flooring and joinery board mentioned E0 grade (0.5mg/L by dryer method), and other materials did not have E0 grade. Results This index was misinterpreted and confused by manufacturers as the general standard of environmental protection grade of various boards, abused and greatly exaggerated by the market, and expanded the E0 grade coverage of laminated wood flooring and blockboard to all board categories.
For example, in the animal world, you should evaluate a climbing skill standard for golden monkeys. The golden monkeys are qualified if their climbing height exceeds 1.0m/ s, and the index of 1.0m/ s is named A0. This standard only applies to the golden monkey world, and A0 level cannot be forcibly applied to proboscis monkeys, elephants, spiders, crocodiles, eagles and other animals.
(Source win4000.com)
Although in the new standard issued by 20 17, the country has cancelled the E0 level index, but E0 has been extended in concept and has become a publicity stunt of enterprises, and it has not been written into the national standard.
Now the popular E0 standard is 0.5mg/L (unit: mg/L), which has become the slogan of commercial activities, so E0 has become a "technical term" in the industry, conceptually creating a hierarchical contempt chain, which makes the E0 standard customized at the next higher level look superior to E 1 and E2.
The concept of E0 level defined by the market has been heated up and has been a popular word for a long time. Coupled with the overwhelming advertising, the public has habitually recognized the name "E0 level". The number "0" in the name is also meaningful, which makes people think E0 is better than E 1, and even thinks E0 level is zero formaldehyde.
Whether it's E0 market level or E 1 new national standard level, don't get entangled in the name, just remember one thing and look for the data of 0. 124mg/m3.
To sum up, we summarize it as the concentrated essence version of lazy people:
1. From the strict degree of environmental protection measures, the CARB standard of the United States and the F-Star standard of Japan are not only aimed at product testing, but also visit and inspect all aspects of the factory and comprehensively evaluate the whole production process and quality system, which are point-to-point quality control mechanisms. For example, in addition to checking children's homework scores, we should also go to their home to find out the situation.
2. The formaldehyde limit values of the new national standard E 1 and the European standard E 1 are the same, both of which are 0. 124mg/m3, and the new international E 1 level is safe enough.
3. The new national standard E 1 is the only national standard at present, without E0 and E2.
4. If the building materials inspection report documents are written in mg/L and mg/ 100g, they are both outdated (old) national standards.
* The above figure shows the unit conversion between the European standard E 1 and the new national standard E 1, with the limit values of 0. 124mg/m3*
Can choosing materials that meet environmental standards avoid the invasion of formaldehyde?
Although the selected items or categories meet the environmental standards, there are usually more than one kind of indoor materials. Even if the formaldehyde emission of each selected material and product does not exceed the standard, it does not mean that the indoor formaldehyde pollution level is within the safe range. The new national standard E 1 only means that the plate meets the national standard when it leaves the factory. In the actual decoration process, the plate will be sawed to expose the cross section, spliced and assembled, glued and painted. , will be destroyed in the process.
Formaldehyde has a superposition effect. All kinds of aldehyde-containing articles are put in a room, and the total amount of formaldehyde released indoors may also exceed the standard if the materials that do not exceed the standard are collectively added up.
The state stipulates that the formaldehyde emission of a class of civil buildings is ≤0.08mg/m3 (residential buildings belong to the first class).
This has created a new problem, how to remove indoor formaldehyde?
Strictly speaking, it should be called governance. Formaldehyde cannot be completely eliminated. In addition to formaldehyde does not mean eliminating formaldehyde. Maybe someone will joke that if I can't get rid of it, I can always live in the embryo room.
Formaldehyde: "You underestimate my penetration in the human world."
Even the embryo room can't escape the invasion of formaldehyde. In building construction, in order to improve the strength of cement and accelerate the setting speed, an admixture containing formaldehyde can be added when mixing concrete.
In fact, there is no need to be too scared. The toxicity of formaldehyde is directly proportional to the dose, just like drinking. It is necessary to control the amount of alcohol. If you break through the upper limit of alcohol that the stomach can bear, it may lead to physical illness and even alcoholism.
Articles containing formaldehyde and articles releasing formaldehyde are different in terms of health hazards.
For example, plastic pots made of aldehyde resin will not volatilize formaldehyde, so people will not breathe free formaldehyde, which will not affect people's health, just like gas pipes containing natural gas in the kitchen and sewage pipes in the bathroom. As long as they don't leak, the pipes won't enter the human respiratory tract in a safe state. Therefore, even if there are objects emitting formaldehyde indoors, it is safe as long as the total amount of formaldehyde released does not exceed the standard.
Substances that release formaldehyde are the main culprit of health. The purpose of controlling indoor formaldehyde is to keep the emission from exceeding the standard and remove it to the minimum as far as possible.
I mentioned three states of indoor formaldehyde. Free and adsorbed formaldehyde is easier to clean. Isn't formaldehyde an organic substance containing carbon molecules (chemical formula CH? O, simple structure HCHO), can it be decomposed into other substances by chemical reaction?
Of course. Therefore, the common folk methods are: green radish, chlorophytum, tea, grapefruit peel and so on. , distributed in every corner and point of the room. They have some effects, but their effects are limited. Most of them are to drive away and cover up the smell in the room. No pungent smell does not mean no formaldehyde, and smelling pungent smell does not mean formaldehyde. Indoor air can be a mixed gas mixed with the smells of various substances, and the human nose is not an accurate detection instrument.
(Source wattsn.com)
Is formaldehyde insoluble in water? Can you put some pots of water? Actually, it has little effect. Formaldehyde molecules are not hungry cats. When they see a pot of cat food, they will jump on it unless they soak the whole house in water. There is also an activated carbon bag, which can only partially absorb formaldehyde nearby. If it is not thrown away in time, it will vomit as the temperature rises, causing secondary pollution.
In order to control formaldehyde, various methods and products emerge one after another in the market, such as air purifier, quick formaldehyde cleaner, scavenger, deodorizing gel and so on. Although it can play a certain role, it is not the best method; There is a specialization in the industry. In order to strengthen the control of formaldehyde, many people will invite professionals outside in addition to formaldehyde to come to their homes for testing and cleaning, which is more efficient and effective than the previous methods.
In contrast, in fact, the most effective and lowest cost way is: ventilation! Get some air. Get some air.
Let the air circulate, and those without ventilation create ventilation conditions artificially. Ventilation can be combined with the above methods to accelerate the removal of formaldehyde attached to the surface of articles and volatilized in the air.
Cleaning up free and adsorbed formaldehyde has passed, and there is still the most important step: the treatment and prevention of bound formaldehyde. The release cycle of some stubbornly bound formaldehyde is as long as 3 ~ 15 years, and it is always impossible to dismantle the internal structure of the object to control it.
Still have to go back to the source. At the beginning of material selection, in addition to meeting environmental protection standards, we should also check the tightness of the material, such as whether the edge of the plate is intact or not. A good process will seal the cross section of the plate tightly, "lock" the combined formaldehyde in the inner core of the plate to prevent it from volatilizing, and at the same time improve the stability of the side structure to prevent moisture from entering the plate, leading to edge warping, mildew and glue opening.
(Sample photos investigated by the design team of knowing and doing in one)
With the continuous progress and development of science, the introduction of environmental protection policies and measures, and the intensification of competition in the building materials market, it is believed that more and more environmental protection materials and in addition to formaldehyde methods have been developed, people's quality of life has improved, and their health requirements have become higher and higher. At present, the most important method of indoor formaldehyde control is to start from the source of materials.
* Original articles, unauthorized reprinting is prohibited *
This answer comes from the design of the integration of knowledge and practice by user Lukeka. For more decoration strategies and home experience, please visit the live APP.