System for identifying content of formaldehyde in formaldehyde solution through color and detection method

Abstract

The invention discloses a system for identifying the content of formaldehyde in a formaldehyde solution through colors, and the system is characterized in that the system comprises a color identification unit which is provided with at least one viewing frame, and the color identification unit carries out the identification of the color of a to-be-detected formaldehyde solution in the viewing frame through calling a camera; the data transmission unit is used for transmitting the color of the to-be-detected formaldehyde solution acquired by the color identification unit; the three-primary color database unit is used for storing at least 27 groups of RGB (Red, Green and Blue) values of the formaldehyde solution from 0mg / m < 3 > to 0.5 mg / m < 3 >; a data comparison unit; the color comparison unit compares the color of the to-be-detected formaldehyde solution transmitted by the data transmission unit with the output stored in the three-primary color database unit; the formaldehyde concentration color detection system has the beneficial effects that the RGB color is adopted to digitalize each concentration color value of formaldehyde, the system does not depend on a color card, and the detection result is more accurate.

Description

Technical Field

[0001] The present invention relates to the technical field of formaldehyde detection, and in particular to a system and a detection method for identifying the formaldehyde content in a formaldehyde solution by color. Background Art

[0002] Commonly used decoration materials, such as paint, coating, floor covering, wallpaper, plywood, plastic, polyvinyl chloride (PVC) board, insulation materials, and indoor artificial boards, such as sandwich panels, ash and other types of board glued veneers, density board furniture and works of art, will release volatile organic compounds. Various countries have conducted a lot of research and discussion on the nature and harm of pollution, among which the most harmful is the formaldehyde pollution that has long been known to people; Formaldehyde has a great impact on the human body. Long-term exposure to formaldehyde-polluted environments can cause the following hazards: chronic respiratory diseases, nasopharyngeal cancer, colon cancer, brain tumors, menstrual disorders, gene mutations in the cell nucleus, cross-linking within a single DNA strand and between DNA and protein, inhibition of DNA damage repair, pregnancy syndrome, chromosomal abnormalities and leukemia in newborns, and decreased memory and intelligence in adolescents. The hazards of formaldehyde are so great that the market demand for formaldehyde detection equipment is also huge; Existing household formaldehyde gas detection products mainly include formaldehyde detectors and formaldehyde gas detection kits. Among them, the existing formaldehyde detection instruments are generally expensive, ranging from hundreds to thousands of yuan. Formaldehyde detectors can be called "useless" for consumers, because after consumers complete the formaldehyde test, the formaldehyde detectors are often idle and will not be used in the future, which causes a waste of resources; another formaldehyde detection product is the formaldehyde gas detection kit. The traditional formaldehyde gas detection kit includes an absorption box, a diluent in a brown reagent bottle, a color developer in a colorless reagent bottle, and a colorimetric card. When testing, you need to tear open the formaldehyde reaction powder reagent package and add it to the absorption box, then add the diluent to the absorption box, and then add the absorption box to the absorption box. Add a color developer, and after a period of time, read the formaldehyde gas concentration against the colorimetric card. For example, the patent number is: Patent number CN108931519B discloses a formaldehyde gas detection box and a detection method. This method and the detection methods in the prior art all use a colorimetric card to compare the color matching between the formaldehyde solution and the colorimetric card. The color that matches indicates the value of the formaldehyde content in the air. However, such methods all have an obvious defect, that is, the colorimetric card is printed by a machine, and the color difference of the ink on the color card is different due to different printing batches, resulting in inaccurate colorimetric results after detection. It is necessary to improve this. Summary of the invention

[0003] The technical problem to be solved by the present invention is to address the deficiencies of the above-mentioned prior art. The invention provides a system for identifying the formaldehyde content in a formaldehyde solution by color, which provides a more accurate identification result.

[0004] To achieve the above object, the present invention provides the following technical solution: a system for identifying the formaldehyde content in a formaldehyde solution by color, characterized in that the system comprises: A color recognition unit having at least one viewfinder, the color recognition unit calls a camera and recognizes the color of the formaldehyde solution to be detected in the viewfinder; A data transmission unit, which is used to transmit the color of the formaldehyde solution to be detected obtained by the color recognition unit; The three-primary color database unit stores at least 27 groups of formaldehyde solutions from 0mg / m 3 -0.5mg / m 3 RGB values ​​between; A data comparison unit; which compares the color of the formaldehyde solution to be detected transmitted by the data transmission unit with the output stored in the three-primary color database unit; Result output unit: it outputs the result obtained after the comparison by the data comparison unit.

[0005] By adopting the above technical scheme, the scheme of the present invention is to transmit the color of the formaldehyde solution to be detected to the data comparison unit through the color recognition unit frame color picking and the data transmission unit to compare with the three primary color data in the three primary color database unit, and then output the compared detection result through the result output unit, such as: 01 Safety level: Formaldehyde concentration ≤ 0.08, basically no symptoms, almost no smell; 02 Easy to cause disease: Formaldehyde concentration 0.1-0.25, people with low immunity will suffer from various diseases, skin allergies, sore throat, and difficulty breathing; formaldehyde concentration 0.2-0.3, the risk factor increases, eyes feel dry, chest tightness, shortness of breath, dizziness, fatigue; 03 Living danger: Formaldehyde concentration of 0.3-0.5 is a very dangerous value, which can easily damage the immune system, cause endocrine disorders, respiratory diseases, and affect children's growth. Formaldehyde concentration of 0.5-0.7 is even more dangerous. Staying in it for a long time will gradually disrupt the immune function, damage the liver, and increase the risk of cancer; formaldehyde concentration of 0.7-1, the risk factor soars, damages various tissues of the body, and the risk of cancer soars; 04 Serious harm: When the formaldehyde concentration exceeds 1 or even 30 times, it is extremely harmful to the human body, causing various serious diseases, including pulmonary edema, leukemia, nasopharyngeal cancer and other cancers, and even death; This method does not rely on color cards and the test results are more accurate.

[0006] The above-mentioned system for identifying the formaldehyde content in a formaldehyde solution by color can be further configured as follows: the establishment of the three-primary color database unit is performed through the following steps: S1: Establish a standard curve of formaldehyde absorbance concentration; S2: Perform data correction on the detected value according to the true value to obtain a curve relationship diagram between the detected value and the true value; S3: Establishing a fitting curve diagram of RGB value and formaldehyde color; S4: 0mg / m 3 -0.2mg / m 3 The formaldehyde solution between them takes the fitting points; S5: 0.2 mg / m 3 -0.5mg / m 3 The formaldehyde solution between them takes the fitting points; S6: Establish a three-primary color database through the RGB values ​​obtained in steps S4 and S5.

[0007] Using the above technical scheme, the method for establishing the formaldehyde absorbance concentration standard curve is as follows: Prepare the formaldehyde standard solution series with reference to the national standard GB / T18204.2-2014 (7.2.5.1), (1) Prepare the formaldehyde standard solution 10 ug / L: Take 1 ml of formaldehyde (1000 ug / L) standard solution and dilute it to 100 ml. (2) Prepare the formaldehyde standard solution (1 ug / L): Add 100 mg of phenol reagent, 5 g of sodium chloride, and 25 ml of formaldehyde standard solution (10 ug / L) to a 250 ml volumetric flask and make up to 250 ml. (3) Prepare the absorption solution: Add 400 mg of phenol reagent and 20 g of sodium chloride to a 1000 ml volumetric flask and make up to 1000 ml. (4) Prepare the color developer: Add 1.0 g of ammonium ferric sulfate to a 100 ml volumetric flask, dissolve it with 0.1 mol / L hydrochloric acid, and make up to 100 ml. (5) Add 0.4 ml of the color developer to the prepared solution and measure the absorbance using a spectrophotometer 15 min after addition; The method for establishing the relationship between the test value and the true value curve is as follows: (1) Take 5 ml of absorption liquid from the plastic test box; (2) Adjust the test environment of the test chamber (200 L) to the required temperature and humidity; (3) Place a test box in the test chamber (200 L); (4) Add the corresponding formaldehyde to the test chamber. After stabilization for 20 min, the test begins, open the test box, and start the timer. The absorption time is 30 min. When the corresponding time is reached, close the test boxes one by one; (5) At the same time, add 5 ml of absorption liquid to the absorption bottle, use an atmospheric sampler to collect the gas in the test chamber at 0.5 L / min for 20 min, and perform two parallel tests; (6) After the test, take out the test box; (7) Add 0.4 ml of color developer to each test box and color develop for 15 min; transfer 5 ml of absorption liquid in the absorption bottle to the sample tube and add 0.4 ml of color developer. Color develop for 15 min. min; (8) After the color development is completed, the absorbance in the detection box and the sample tube is measured by spectrophotometry, and the corresponding formaldehyde concentration value is calculated by the standard curve, such as Figure 1 As shown; the current sampling method uses a detection box filled with absorption liquid placed in a closed cabin, which is quite different from the standard sampling method. The standard method uses an air pump bubbling method, and the gas passes through the absorption liquid, and the formaldehyde is completely absorbed; the detection box is placed in the cabin, and only the surface solution absorbs formaldehyde. The two methods are quite different, and data correction is required. Through data verification, the difference in formaldehyde values ​​between the bubbling method and the absorption method is compared, and a curve relationship diagram of the detection value and the true value is obtained, as shown Figure 2 As shown; The RGB value and formaldehyde color fitting curve is as follows Figure 3 As shown, the preparation method is to prepare formaldehyde standard solution, absorption solution, color developer and other sample solutions, mix the prepared test solution with the color developer and react for 15 minutes, observe the color and adjust it to the corresponding RGB value through a computer; according to Figure 3 It can be seen that RGB satisfies the corresponding relationship: R value = 248.96-728.55x, G value = 240.63-186.90x, B value = 248.25-99.5x, where RGB mode = {(r, g, b) | 0≤r≤255, 0≤g≤255, 0≤b≤255}. The fitting points can be listed as follows Figure 4 , Figure 5 As shown by Figure 4 , Figure 5 It can be seen that selecting 27 groups of color numbers can basically guarantee the formaldehyde detection requirements for civilian homes. The formaldehyde sampling points are in the range of 0-0.2, and the accuracy is 0.01 mg / m3.

[0008] The above-mentioned system for identifying the formaldehyde content in a formaldehyde solution by color can be further configured as follows: in step S4, 0 mg / m 3 -0.2mg / m3 The fitting points are taken for the formaldehyde solution between .

[0009] The above-mentioned system for identifying the formaldehyde content in a formaldehyde solution by color can be further configured as follows: in step 5, 0.2 mg / m 3 -0.5mg / m 3 Take the fitting points for the formaldehyde solution between .

[0010] By adopting the above technical solution, the formaldehyde sampling points are within the range of 0-0.2, and the selection of 27 groups of color numbers can basically guarantee the formaldehyde detection requirements for civilian homes.

[0011] The above-mentioned system for identifying the formaldehyde content in a formaldehyde solution by color can be further configured as follows: the result output unit outputs the result including: when the formaldehyde concentration is 0.08 mg / m 3 -0.1mg / m 3 When the formaldehyde concentration is between 0.1mg / m 3 -0.25mg / m 3 When the formaldehyde concentration is between 0.3mg / m 3 -0.5mg / m 3 When the formaldehyde concentration exceeds 0.5mg / m 3 Output "serious harm".

[0012] With the above technical solution, when the formaldehyde concentration is ≤0.08, there are basically no symptoms, and the smell is almost inaudible and irritation is not felt; when the formaldehyde concentration is 0.08-0.1, there will be signs of mild formaldehyde poisoning, which may be slightly irritating, and dizziness, eye, nose and throat pain will occur over time; when the formaldehyde concentration is 0.1-0.25, people with low immunity will develop various diseases, such as skin allergies, sore throat, and difficulty breathing; when the formaldehyde concentration is 0.2-0.3, the risk factor increases, and the eyes feel dry, the chest feels short of breath, dizziness, and fatigue; when the formaldehyde concentration is 0 .3-0.5 is a very dangerous value, which can easily damage the immune system, cause endocrine disorders, respiratory diseases, and affect children's growth. Formaldehyde concentration of 0.5-0.7 is even more dangerous. Staying in it for a long time will gradually disrupt the immune function, damage the liver, and increase the risk of cancer; formaldehyde concentration of 0.7-1, the risk factor soars sharply, damaging various body tissues and the risk of cancer; when the formaldehyde concentration exceeds 1 or even 30 times, it is extremely harmful to the human body, causing various serious diseases, pulmonary edema, leukemia, nasopharyngeal carcinoma and other cancers, and even death.

[0013] A method for detecting a system for identifying the formaldehyde content in a formaldehyde solution by color, characterized in that it comprises the following steps: Step 1: Pick the color of the formaldehyde solution to be detected through the frame of the color recognition unit; Step 2: Transmit the color obtained by the color recognition unit to the data comparison unit through the data transmission unit for comparison with the three-primary color data in the three-primary color database unit; Step 3: The result output unit outputs the result compared by the data comparison unit and displays the test result.

[0014] By adopting the above technical solution, since the detection does not rely on the color card, but is displayed after converting the RGB color value into the corresponding concentration data, the detection result is more accurate.

[0015] The beneficial effects of the present invention are as follows: the color values ​​of each formaldehyde concentration are digitized using RGB color data, which is independent of color cards and makes the detection result more accurate. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 The corresponding formaldehyde concentration value is calculated by the standard curve in the embodiment of the present invention; Figure 2 A curve relationship diagram of the detected value and the true value of an embodiment of the present invention; Figure 3 It is a fitting curve diagram of RGB value and formaldehyde color of an embodiment of the present invention; Figure 4 is a fitting point data table of an embodiment of the present invention; Figure 5 This is a corresponding relationship diagram between RBG and formaldehyde concentration in an embodiment of the present invention; Figure 6 The formaldehyde concentration values ​​in some embodiments of the present invention correspond to the RGB fitting points; DETAILED DESCRIPTION

[0017] See also Figures 1 to 5 As shown: A system for identifying the formaldehyde content in a formaldehyde solution by color, characterized in that the system comprises: A color recognition unit having at least one viewfinder, the color recognition unit calls a camera and recognizes the color of the formaldehyde solution to be detected in the viewfinder; A data transmission unit, which is used to transmit the color of the formaldehyde solution to be detected obtained by the color recognition unit; The three-primary color database unit stores at least 27 groups of formaldehyde solutions from 0mg / m 3 -0.5mg / m 3 RGB values ​​between; A data comparison unit; which compares the color of the formaldehyde solution to be detected transmitted by the data transmission unit with the output stored in the three-primary color database unit; Result output unit: it outputs the result obtained after the comparison by the data comparison unit.

[0018] The scheme of the present invention is to take the color of the formaldehyde solution to be detected by the color recognition unit frame, and transmit it to the data comparison unit through the data transmission unit to compare it with the three primary color data in the three primary color database unit. After the comparison, the result output unit outputs the compared detection result, such as: 01 Safety level: Formaldehyde concentration ≤ 0.08, basically no symptoms, almost no smell; 02 Easy to cause disease: Formaldehyde concentration 0.1-0.25, people with low immunity will suffer from various diseases, skin allergies, sore throat, and difficulty breathing; formaldehyde concentration 0.2-0.3, the risk factor increases, eyes feel dry, chest tightness, shortness of breath, dizziness, fatigue; 03 Living danger: Formaldehyde concentration of 0.3-0.5 is a very dangerous value, which can easily damage the immune system, cause endocrine disorders, respiratory diseases, and affect children's growth. Formaldehyde concentration of 0.5-0.7 is even more dangerous. Staying in it for a long time will gradually disrupt the immune function, damage the liver, and increase the risk of cancer; formaldehyde concentration of 0.7-1, the risk factor soars, damages various tissues of the body, and the risk of cancer soars; 04 Serious harm: When the formaldehyde concentration exceeds 1 or even 30 times, it is extremely harmful to the human body, causing various serious diseases, including pulmonary edema, leukemia, nasopharyngeal cancer and other cancers, and even death; This method does not rely on color cards, and the test results are more accurate; The establishment of the three-primary color database unit goes through the following steps: S1: Establish a standard curve of formaldehyde absorbance concentration; S2: Perform data correction on the detected value according to the true value to obtain a curve relationship diagram between the detected value and the true value; S3: Establishing a fitting curve diagram of RGB value and formaldehyde color; S4: 0mg / m 3 -0.2mg / m 3 The formaldehyde solution between them takes the fitting points; S5: 0.2 mg / m 3 -0.5mg / m 3 The formaldehyde solution between them takes the fitting points; S6: Establish a three-primary color database through the RGB values ​​obtained in steps S4 and S5.

[0019] The method for establishing the formaldehyde absorbance concentration standard curve is as follows: Prepare the formaldehyde standard solution series according to the national standard GB / T 18204.2-2014 (7.2.5.1), (1) Prepare the formaldehyde standard solution 10 ug / L: Take 1 ml of formaldehyde (1000 ug / L) standard solution and dilute it to 100 ml. (2) Prepare the formaldehyde standard solution (1 ug / L): Add 100 mg of phenol reagent, 5 g of sodium chloride, and 25 ml of formaldehyde standard solution (10 ug / L) to a 250 ml volumetric flask and make up to 250 ml. (3) Prepare the absorption solution: Add 400 mg of phenol reagent and 20 g of sodium chloride to a 1000 ml volumetric flask and make up to 1000 ml. (4) Prepare the color developer: Add 1.0 g of ammonium ferric sulfate to a 100 ml volumetric flask, dissolve it with 0.1 mol / L hydrochloric acid, and make up to 100 ml. (5) Add 0.4 ml of the color developer to the prepared solution and measure the absorbance using a spectrophotometer 15 min after addition; The method for establishing the relationship between the test value and the true value curve is as follows: (1) Take 5 ml of absorption liquid from the plastic test box; (2) Adjust the test environment of the test chamber (200 L) to the required temperature and humidity; (3) Place a test box in the test chamber (200 L); (4) Add the corresponding formaldehyde to the test chamber. After stabilization for 20 min, the test begins, open the test box, and start the timer. The absorption time is 30 min. When the corresponding time is reached, close the test boxes one by one; (5) At the same time, add 5 ml of absorption liquid to the absorption bottle, use an atmospheric sampler to collect the gas in the test chamber at 0.5 L / min for 20 min, and perform two parallel tests; (6) After the test, take out the test box; (7) Add 0.4 ml of color developer to each test box and color develop for 15 min; transfer 5 ml of absorption liquid in the absorption bottle to the sample tube and add 0.4 ml of color developer. Color develop for 15 min. min; (8) After the color development is completed, the absorbance in the detection box and the sample tube is measured by spectrophotometry, and the corresponding formaldehyde concentration value is calculated by the standard curve, such as Figure 1 As shown; the current sampling method uses a detection box filled with absorption liquid placed in a closed cabin, which is quite different from the standard sampling method. The standard method uses an air pump bubbling method, and the gas passes through the absorption liquid, and the formaldehyde is completely absorbed; the detection box is placed in the cabin, and only the surface solution absorbs formaldehyde. The two methods are quite different, and data correction is required. Through data verification, the difference in formaldehyde values ​​between the bubbling method and the absorption method is compared, and a curve relationship diagram of the detection value and the true value is obtained, as shown Figure 2 As shown; The RGB value and formaldehyde color fitting curve is as follows Figure 3 As shown, the preparation method is to prepare formaldehyde standard solution, absorption solution, color developer and other sample solutions, mix the prepared test solution with the color developer and react for 15 minutes, observe the color and adjust it to the corresponding RGB value through a computer; according to Figure 3 It can be seen that RGB satisfies the corresponding relationship: R value = 248.96-728.55x, G value = 240.63-186.90x, B value = 248.25-99.5x, where RGB mode = {(r, g, b) | 0≤r≤255, 0≤g≤255, 0≤b≤255}. The fitting points can be listed as follows Figure 4 , Figure 5 , Figure 6 As shown by Figure 4 , Figure 5 It can be seen that selecting 27 groups of color numbers can basically guarantee the formaldehyde detection requirements for civilian homes. The formaldehyde sampling points are in the range of 0-0.2, and the accuracy is 0.01 mg / m3.

[0020] In step S4, 0 mg / m 3 -0.2mg / m 3 The fitting points are taken for the formaldehyde solution between .

[0021] In step 5, 0.2 mg / m 3 -0.5mg / m 3 The fitting points are taken for the formaldehyde solution between .

[0022] The formaldehyde sampling point is within the range of 0-0.2, and the selection of 27 groups of color numbers can basically guarantee the formaldehyde detection requirements for civilian homes; The output results of the result output unit include: when the formaldehyde concentration is 0.08mg / m 3 -0.1mg / m 3 When the formaldehyde concentration is between 0.1mg / m 3 -0.25mg / m 3 When the formaldehyde concentration is between 0.3mg / m 3 -0.5mg / m 3 When the formaldehyde concentration exceeds 0.5mg / m 3 Output "serious harm"; When the formaldehyde concentration is ≤0.08, there are basically no symptoms, and you can hardly smell the odor or feel the irritation. When the formaldehyde concentration is 0.08-0.1, there will be signs of mild formaldehyde poisoning, which may be slightly irritating. After a long time, you will feel dizzy and have eye, nose and throat pain. When the formaldehyde concentration is 0.1-0.25, people with low immunity will develop various diseases, such as skin allergies, sore throat and shortness of breath. When the formaldehyde concentration is 0.2-0.3, the risk factor increases, and you will feel dry eyes, chest tightness, shortness of breath, dizziness and fatigue. When the formaldehyde concentration is 0.3-0 .5 is a very dangerous value, which can easily damage the immune system, cause endocrine disorders, respiratory diseases, and affect children's growth. Formaldehyde concentration of 0.5-0.7 is more dangerous. Staying in it for a long time will gradually disrupt the immune function, damage the liver, and increase the risk of cancer; formaldehyde concentration of 0.7-1, the risk factor soars sharply, damages various tissues of the body, and the risk of cancer increases sharply; when the formaldehyde concentration exceeds 1, or even 30 times, it is extremely harmful to the human body, causing various serious diseases, pulmonary edema, leukemia, nasopharyngeal cancer and other cancer diseases, and even death; A method for detecting a system for identifying the formaldehyde content in a formaldehyde solution by color, characterized in that it comprises the following steps: Step 1: Pick the color of the formaldehyde solution to be detected through the frame of the color recognition unit; Step 2: Transmit the color obtained by the color recognition unit to the data comparison unit through the data transmission unit for comparison with the three-primary color data in the three-primary color database unit; Step 3: The result output unit outputs the result compared by the data comparison unit and displays the test result.

[0023] By adopting the above technical solution, since the detection does not rely on the color card, but is displayed after converting the RGB color value into the corresponding concentration data, the detection result is more accurate.

[0024] Beneficial effect: The color values ​​of each formaldehyde concentration are digitized using RGB color data, which does not rely on color cards and the test results are more accurate.

Claims

1. A system for identifying the formaldehyde content in a formaldehyde solution by color, characterized in that: The system comprises: A color recognition unit having at least one viewfinder, the color recognition unit calls a camera and recognizes the color of the formaldehyde solution to be detected in the viewfinder; A data transmission unit, which is used to transmit the color of the formaldehyde solution to be detected obtained by the color recognition unit; The three-primary color database unit stores at least 27 groups of formaldehyde solutions from 0mg / m 3 -0.5mg / m 3 RGB values ​​between; A data comparison unit; which compares the color of the formaldehyde solution to be detected transmitted by the data transmission unit with the output stored in the three-primary color database unit; Result output unit: it outputs the result obtained after the comparison by the data comparison unit.

2. A system for identifying the formaldehyde content in a formaldehyde solution by color according to claim 1, characterized in that: The establishment of the three-primary-color database unit is carried out through the following steps: S1: Establish a standard curve of formaldehyde absorbance concentration; S2: Perform data correction on the detected value according to the true value to obtain a curve relationship diagram between the detected value and the true value; S3: Establishing a fitting curve diagram of RGB value and formaldehyde color; S4: 0mg / m 3 -0.2mg / m 3 The formaldehyde solution between them takes the fitting points; S5: 0.2 mg / m 3 -0.5mg / m 3 The formaldehyde solution between them takes the fitting points; S6: Establish a three-primary color database through the RGB values ​​obtained in steps S4 and S5.

3. A system for identifying the formaldehyde content in a formaldehyde solution by color according to claim 2, characterized in that: In step S4, 0 mg / m 3 -0.2mg / m 3 The fitting points are taken for the formaldehyde solution between .

4. A system for identifying formaldehyde content in a formaldehyde solution by color according to claim 2, characterized in that: In step 5, 0.2 mg / m 3 -0.5mg / m 3 The fitting points are taken for the formaldehyde solution between .

5. The system for identifying the formaldehyde content in a formaldehyde solution by color according to claim 1, characterized in that: The output result of the result output unit includes: when the formaldehyde concentration is 0.08mg / m 3 -0.1mg / m 3 When the formaldehyde concentration is between 0.1mg / m 3 -0.25mg / m 3 When the formaldehyde concentration is between 0.3mg / m 3 -0.5mg / m 3 When the formaldehyde concentration exceeds 0.5mg / m 3 Output "serious harm".

6. A detection method using a system for identifying the formaldehyde content in a formaldehyde solution by color according to any one of claims 1 to 5, characterized in that: The following steps are involved: Step 1: Pick the color of the formaldehyde solution to be detected through the frame of the color recognition unit; Step 2: Transmit the color obtained by the color recognition unit to the data comparison unit through the data transmission unit for comparison with the three-primary color data in the three-primary color database unit; Step 3: The result output unit outputs the result compared by the data comparison unit and displays the test result.

Images