JP4037672B2 - Simple measurement method for formaldehyde concentration in houses - Google Patents

Description

【００４６】
次に、検知管によるアセトアルデヒドの検出感度（α）を算出する。検出感度（α）は、検知管による測定値と、ＤＮＰＨ法によるホルムアルデヒド濃度・アセトアルデヒド濃度から求めた。α＝０．７９９７と仮定して、検知管測定値に対する式１による計算値をプロットすると、図１のように相関線がほぼｙ＝ｘに重なった。これにより、式１が成り立つことがわかった。
【００４７】
検知管測定値＝ＤＮＰＨ法ホルムアルデヒド濃度＋０．７９９７×ＤＮＰＨ法アセトアルデヒド濃度・・・式１
【００４８】
次に、住宅内のアセトアルデヒド、ホルムアルデヒド濃度と温度の関係を調べた。アセトアルデヒド濃度とホルムアルデヒド濃度の比と測定時の温度とをプロットすると、図２に示す相関が認められた。温度が低いほどアセトアルデヒドの濃度が高く、温度が高くなるに従って、ホルムアルデヒドの濃度が上昇することが分かり、図２から式２で相関を表せることがわかった。
【００４９】
ＤＮＰＨ法アセトアルデヒド濃度／ＤＮＰＨ法ホルムアルデヒド濃度＝１．０４−０．０２５７×温度・・・式２
【００５０】
この式１及び式２から、ＤＮＰＨ法アセトアルデヒド濃度を消去して、検知管法測定値とＤＮＰＨ法ホルムアルデヒド濃度の相関を示す式３を誘導した。
【００５１】
検知管測定値＝ＤＮＰＨ法ホルムアルデヒド濃度＋０．７９９７×ＤＮＰＨ法ホルムアルデヒド濃度×（１．０４−０．０２５７×温度）・・・式３
【００５２】
式３は、式４に変形することにより、検知管法の測定結果から、ＤＮＰＨ法ホルムアルデヒド濃度を推定算出する補正換算式として使用できる。
【００５３】
ＤＮＰＨ法ホルムアルデヒド濃度＝検知管測定値／｛１＋０．７９９７×（１．０４−０．０２５７×温度）｝・・・式４
【００５４】
得られた補正換算式（式４）を用いて、表１の検知管測定値からＤＮＰＨ法ホルムアルデヒド濃度を推定算出した場合のＤＮＰＨ法推定値と、実際のＤＮＰＨ法ホルムアルデヒド濃度をプロットすると、図３に示すように非常に良好な相関を示すことが分かった。
こうして、実施例１〜８によって得た検知管測定値と温度データから、相関式によってＤＮＰＨ法ホルムアルデヒド濃度が算出できるから、住宅のホルムアルデヒド濃度を検知管によって簡易に測定できることになる。
【００５５】
【発明の効果】
本発明によれば、住宅からホルムアルデヒド濃度を簡易かつ迅速に評価でき、検知管法の測定精度を向上できる。したがって、この方法を用いれば建物内のホルムアルデヒド濃度が充分に低減したことを確認後、新築住宅を引き渡すことが可能となり極めて有用である。
【図面の簡単な説明】
【図１】検知管による測定値と、ＤＮＰＨ法によるアセトアルデヒド濃度とホルムアルデヒド濃度を用いたアセトアルデヒドの検出感度を示すグラフである。
【図２】住宅内のアセトアルデヒド濃度とホルムアルデヒド濃度の相関を示すグラフである。
【図３】ＤＮＰＨ法によるホルムアルデヒド濃度の測定値と、補正換算した検知管測定による推定値との相関を示すグラフである。[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a simple method for measuring the formaldehyde concentration in a house and a method for providing a house using the same, and more specifically, the formaldehyde concentration in a house can be easily measured on-site, and sufficient accuracy can be ensured while being economical. The present invention relates to a simple method for measuring formaldehyde concentration in a house and a method for providing a house using the same.
[0002]
[Prior art]
In recent years, sick house syndrome in new and renovated houses has become a social problem. This is a case in which a resident who has moved into a newly-built building or after renovation complains of headache, dizziness, autonomic modulation, chronic fatigue or other health problems, but is accompanied by skin and visceral diseases Sometimes.
[0003]
The causative substances are organic solvents such as toluene, xylene and acetone released from building materials and furniture, organic phosphorus flame retardant plasticizers such as formaldehyde and tricresyl phosphate, and various organic compounds such as phthalic acid plasticizers , Also called harmful substances).
[0004]
Among them, formaldehyde is an organic chemical substance that exists as a gas at room temperature and emits a strange odor, but its aqueous solution is often used as an adhesive for plywood and particle board, especially for newly built houses (hereinafter, including renovated houses). A large amount of formaldehyde is generated in the building). For this reason, in order to provide a new house, it is necessary to remove and reduce formaldehyde to a level that does not impair health before delivery to the resident.
[0005]
To remove harmful substances such as formaldehyde, use a natural ventilation opening provided in the building and install ventilation fans and exhaust fans here to ventilate for a long time. A bakeout method that heats and accelerates the release of harmful substances is known, but the index that objectively determines the delivery time has not always been clear.
[0006]
To accurately measure the formaldehyde concentration in buildings, the DNPH method or AHMT method is used. However, the measurement cost is high, the analysis equipment is expensive, and not only an analyst with specialized knowledge is required. It took a long time to get the measurement results.
[0007]
The DNPH method uses a pump through a hazardous substance collecting device called a DNPH cartridge to pass on-site air, collects formaldehyde in the air inside the cartridge, takes it back to the analysis room, and collects the collected formaldehyde as a solvent. And then separated and detected by a liquid chromatograph (HPLC) apparatus.
[0008]
On the other hand, although the measurement accuracy is inferior to that of the DNPH method, a simple measurement method for formaldehyde has been proposed in which the measurement cost per time is small and the result can be obtained easily and quickly on site.
[0009]
The detector tube method known as a simple measurement method is said to be able to measure up to a considerably low concentration region when used in combination with a metering pump.
For example, Japanese Patent Application Laid-Open No. 2001-272314 discloses a gas concentration measurement for measuring an organic solvent (for example, toluene, formaldehyde, etc.) volatilized in the air from an adhesive sheet, an adhesive tape, or the like attached to wallpaper, building material, or the like. Jigs have been proposed. In this method, an adhesive tape or the like is wound around a cylindrical body of a jig, and gas volatilized from a hole provided in the cylindrical body is measured.
[0010]
Furthermore, Japanese Patent Application Laid-Open No. 10-197420 proposes an apparatus and a measuring method for measuring harmful substances such as formaldehyde diffused from building materials. Covers at least a part of the building material, stores gaseous harmful substances released from the material in a gas storage member, and measures the concentration with a gas detector tube, etc., but can only evaluate individual members .
[0011]
For example, a diffusion gas concentration detection tube is proposed in which a transparent porous tube and a carrier (detection agent) containing a reagent that changes color when in contact with the detection gas are concentrically arranged inside the transparent tube. And is described in Utility Model Registration No. 3015320.
Commercial products of diffusion type gas concentration detector tubes (manufactured by Gastec) include products with a detection limit of 0.05 ppm and a minimum scale width of 0.05 ppm, but housing formaldehyde ranges from 0.01 to 0.10 ppm. The accuracy is not enough to measure with.
[0012]
On the other hand, the detector tube using the filler in which hydroxylamine phosphate is attached to the carrier is a method using the phenomenon that hydroxylamine phosphate reacts with formaldehyde and changes color, and the formaldehyde concentration range in the house is Since it can be measured sufficiently with a minimum scale width of 0.01 ppm, it is considered effective for measuring formaldehyde contained in the air in the house.
[0013]
However, such a detector tube method using hydroxylamine phosphate simultaneously detects chemical substances other than formaldehyde, and shows a higher measurement value than the actual measurement. Therefore, simple measurement that can accurately and economically measure formaldehyde concentration. The method was anxious.
[0014]
[Problems to be solved by the invention]
In view of the problems of the prior art described above, an object of the present invention is to easily measure the formaldehyde concentration of a house on site, and to provide a simple method for measuring the formaldehyde concentration of a house that can ensure sufficient accuracy while being economical. The purpose is to provide a delivery method for the new house used.
[0015]
[Means for Solving the Problems]
As a result of intensive studies to solve the above-mentioned problems, the present inventor found that when hydroxylamine phosphate was simply measured using a detector tube filled with hydroxylamine phosphate, the hydroxylamine phosphate was acetaldehyde. Therefore, the present inventors have completed the present invention by finding that the measurement error of formaldehyde can be kept within an allowable range by subtracting the acetaldehyde concentration from the measured value of the detector tube.
[0016]
That is, according to the first invention of the present invention, the air in a house containing formaldehyde is introduced into a detector tube filled with a filler that utilizes the reaction between hydroxylamine phosphate and formaldehyde and measured. A simple method for measuring formaldehyde concentration,
After the mechanical ventilation equipment has been operated for 5 days or more after the completion of the house, the air in the house is introduced into the detector tube, and the measured values obtained from the detector tube are subjected to the DNPH method and the detector tube method under the same conditions. A simple method for measuring formaldehyde concentration in a house, wherein the measurement error of formaldehyde concentration is corrected by subtracting the equivalent amount of acetaldehyde concentration obtained from the correlation equation obtained from the correlation between measured formaldehyde concentration and acetaldehyde concentration measurement value Is provided.
[0020]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, a simple method for measuring formaldehyde in a house according to the present invention and a method for providing a new house using the same will be described in detail.
[0021]
1. Formaldehyde measurement method The formaldehyde measurement method of the present invention is a method for simply measuring formaldehyde contained in the air in a house, and is characterized by filling a carrier (silica) impregnated with hydroxylamine phosphate. This is to correct the measurement error of the formaldehyde concentration by introducing air containing formaldehyde into the detected tube and subtracting the amount corresponding to the acetaldehyde concentration from the measured value by the detector tube.
[0022]
Houses to be measured are mainly new houses that are less than one year old, but are not limited to those that have been renovated, such as floors and walls, as well as those that have symptoms of Housesick Syndrome. included.
[0023]
The detector tube is not particularly limited as long as it uses a filler in which hydroxylamine phosphate is added to a carrier and can measure the degree of discoloration caused by contact with formaldehyde. The shape of the detector tube is cylindrical or rectangular. Various shapes can be used. Although not limited, the elongated one can cope with detection of a trace component, and generally has a diameter of about 3 mm to 1 cm and a length of about 5 to 20 cm. In order to introduce air containing formaldehyde into the detector tube, a metering pump is usually used.
[0024]
In the present invention, the measurement error of the formaldehyde concentration is corrected by subtracting the amount corresponding to the acetaldehyde concentration obtained from the correlation equation prepared in advance from the measured value by the detector tube.
[0025]
As a result of detailed evaluation of the factors that the other components give to the accuracy of the simple measurement method of formaldehyde concentration using the detector tube method, the following was confirmed.
[0026]
(1) In the detector tube method utilizing the reaction of hydroxylamine phosphate, the components detected in addition to formaldehyde are acetaldehyde, acetone, toluene, methyl ethyl ketone, etc. Among them, acetaldehyde and acetone are strongly detected, and the components to the house are detected. In terms of actual usage, the component that causes measurement error can be almost limited to acetaldehyde.
(2) In the presence of formaldehyde / acetaldehyde, the sensitivity of the detector tube to acetaldehyde is almost constant.
(3) In a standard house, when ventilation of the entire air in a building is continued with mechanical ventilation equipment for more than 5 days after completion, the ratio of acetaldehyde concentration to formaldehyde concentration at the same point shows a substantially constant correlation with temperature. .
[0027]
As described above, since the presence of acetaldehyde is involved in the measured value of formaldehyde concentration by the detector tube, in order to correct the measurement error, a method in which acetaldehyde is previously removed from the air in the house with an adsorption tube or the like However, there is no affordable acetaldehyde adsorption tube, which is unrealistic.
[0028]
On the other hand, in the present invention, a correlation equation for correcting the measured value of formaldehyde concentration by the detector tube is obtained and the measurement error is corrected, so that the error can be within 30%. This clears the error standard in the air pollution manual compiled by the Ministry of the Environment and can be said to be an extremely practical method.
[0029]
2. Method for correcting measurement error of formaldehyde concentration In order to correct measurement error of formaldehyde concentration according to the present invention, first, as an object to be measured, the inner wall / ceiling was a construction board and vinyl wallpaper, which was a general configuration in the house to be evaluated. Then, a house whose floor is composed of flooring with composite plywood or tatami finish is selected as a standard house. For a prefabricated house such as a prefabricated house, the house of that specification may be a standard house.
[0030]
In order to obtain the correlation equation, data storage of at least 10 points, preferably 20 points or more is required in a standard house. They are preferably collected from 2 to 5 measuring points each from a plurality of houses in different environments.
[0031]
It is desirable that the house has mechanical ventilation equipment having a performance of 0.5 to 1.0 ventilation / hour. The mechanical ventilation equipment is a device such as an electric fan that is attached to an opening and sucks or exhausts air. When the operation of the mechanical ventilation equipment is less than 0.5 times / hour, the measurement accuracy is low due to insufficient ventilation. On the other hand, even if the mechanical ventilation equipment is operated more than 1.0 times / hour, no significant improvement in accuracy can be expected. It is desirable to keep the mechanical ventilation equipment continuously operated and ventilate the entire interior of the house for 5 days or more after the completion of the house. Driving for less than 5 days is not preferable because the concentration of formaldehyde in the house varies widely.
[0032]
Next, the inside of a standard house will be in a state where the formaldehyde concentration can be measured. This preparatory stage is performed in accordance with specific concentration measurement conditions including the Ministry of Health, Labor and Welfare guidelines (time management).
[0033]
In other words, as time management, before the formaldehyde measurement, all the openings of the house facing the outside are once opened for 30 minutes or more, then the openings are closed, and the regular ventilation by the mechanical ventilation equipment is operated and held for 5 hours or more. . If the open time is less than 30 minutes or the constant ventilation is less than 5 hours, there is a problem that the measured value varies greatly.
[0034]
After that, the formaldehyde concentration is measured. In the detector tube method, the measured values are read from the length of the discoloration area of the detector tube at the end of air sampling. In the DNPH method, they are collected in a dedicated collector tube. After adsorbing, collecting air and transporting it in an airtight manner, formaldehyde and acetaldehyde, which are collected components of the collection tube, are analyzed at a place where the analyzer is located. In any method, by collecting air at the same time in the same room, the concentration of formaldehyde is measured under the same conditions.
[0035]
It is desirable that the formaldehyde concentration varies within a range of 5 ° C. or higher. This is because the correction formula depends on temperature as will be described later. In addition, the reason for measuring under the temperature condition which is a general living environment is that the house sick syndrome due to formaldehyde occurs in this region.
[0036]
Finally, the correlation equation is obtained from the formaldehyde concentration actually measured by the detector tube method and the DNPH method, or from the correlation between this and the measured value of the acetaldehyde concentration. The details are shown in the Examples, but the measurement error of the formaldehyde concentration by the detector tube method is corrected by this correlation equation.
[0037]
3. Method for Providing Newly Built House The method for providing a newly built house of the present invention is to operate the mechanical ventilation equipment after the building is completed, and when the formaldehyde concentration in the air is sufficiently stabilized and reduced, the concentration is measured by the above simple measuring method. It is characterized by handing over the building if it is inspected and a concentration level below the acceptable formaldehyde level that does not harm health is confirmed.
[0038]
That is, it is a method of handing over a building to a resident after inspecting a newly built house using the above-described simple measuring method of formaldehyde concentration and confirming that the formaldehyde concentration is 0.08 ppm or less in terms of 23 ° C.
[0039]
Normally, in order to open the building opening and operate the mechanical ventilation equipment, it is necessary to continuously ventilate the mechanical ventilation equipment by continuously operating it for 5 days or more, preferably 7 days or more after the construction work of the building is completed. is there.
[0040]
In buildings where the amount of formaldehyde used is low, the air temperature is high, the wind speed is high, and the weather conditions are good for ventilation, such as regular ventilation for 5 days. On the contrary, when the amount of formaldehyde used is high or the temperature is low, If the weather conditions have poor ventilation effects, such as a low wind speed, a period of 7 days or more is required.
Needless to say, the present invention can be applied not only to a newly-built house but also to a case where the house is moved in after a large-scale renovation.
[0041]
【Example】
EXAMPLES Hereinafter, although this invention is demonstrated based on an Example, this invention is not limited by this. The measurement method is as follows.
[0042]
1. Concentration measurement by detector tube method and DNPH method (measuring device, sampling conditions)
1) Detector tube method Detector tube: Kitagawa type detector tube (710 type) manufactured by Komyo Riken, Ltd., Suction pump: S-21 manufactured by Komyo Institute of Science (9L suction volume, 30 minutes suction time) was used.
The detector tube reads the indicated value at a standard time of 30 minutes. However, when the concentration is high, the scale may be shaken off. In that case, the reading value in 30 minutes is estimated from the reading in 10 minutes or the reading in 20 minutes, and 10 minutes reading × 4.0 = 30 minutes reading, 20 minutes reading × 1.69 = The reading was 30 minutes.
[0043]
2) DNPH method collection tube: Seps-Pak DNPH Xposition manufactured by Waters
The concentration of formaldehyde and acetaldehyde was quantitatively analyzed at Ibaraki Environmental Technology Center Co., Ltd., using WAT047295, suction pump: S-21 (Mitsuakeri Science Co., Ltd., S-21, suction amount: 30 L, suction time: 1 hour).
[0044]
(Examples 1-8)
After the construction of the house is completed, it is continuously ventilated (continuous operation) with mechanical ventilation equipment for 5 days, and all the openings facing the outside are once opened for 30 minutes, and then the openings facing the outside of the house (windows, entrances) Etc.), the doors between the rooms were closed and kept for 10 hours with constant ventilation, and then the concentrations of formaldehyde and acetaldehyde were measured.
For the houses, eight buildings with different geographical environments and 26 rooms were selected, and the concentrations of formaldehyde and acetaldehyde were quantitatively analyzed by the DNPH method and the detector tube method, respectively. The number of ventilations in the measurement chamber was measured by an attenuation method using SF ₆ as the tracer gas. The measurement results are shown in Table 1.
[0045]
[Table 1]

[0046]
Next, the detection sensitivity (α) of acetaldehyde by the detection tube is calculated. The detection sensitivity (α) was determined from the measured value by the detector tube and the formaldehyde concentration / acetaldehyde concentration by the DNPH method. Assuming that α = 0.7997, when plotting the calculated value according to Equation 1 against the detector tube measurement value, the correlation line almost overlapped with y = x as shown in FIG. Thereby, it turned out that Formula 1 is formed.
[0047]
Detector tube measurement value = DNPH method formaldehyde concentration + 0.7997 × DNPH method acetaldehyde concentration: Formula 1
[0048]
Next, the relationship between the acetaldehyde and formaldehyde concentrations in the house and the temperature was examined. When the ratio of the acetaldehyde concentration and the formaldehyde concentration and the temperature at the time of measurement were plotted, the correlation shown in FIG. 2 was recognized. The lower the temperature, the higher the concentration of acetaldehyde, and the higher the temperature, the higher the concentration of formaldehyde. From FIG.
[0049]
DNPH method acetaldehyde concentration / DNPH method formaldehyde concentration = 1.04-0.0257 x temperature ... Formula 2
[0050]
From Equation 1 and Equation 2, the DNPH method acetaldehyde concentration was eliminated, and Equation 3 showing the correlation between the detector tube method measurement value and the DNPH method formaldehyde concentration was derived.
[0051]
Detector tube measurement value = DNPH method formaldehyde concentration + 0.7997 × DNPH method formaldehyde concentration × (1.04-0.0257 × temperature) Equation 3
[0052]
Equation 3 can be used as a correction conversion equation for estimating and calculating the DNPH method formaldehyde concentration from the measurement result of the detector tube method by being transformed into Equation 4.
[0053]
DNPH method formaldehyde concentration = detector tube measurement value / {1 + 0.7997 × (1.04-0.0257 × temperature)} Equation 4
[0054]
Using the obtained correction conversion formula (Formula 4), the DNPH method estimated value when the DNPH method formaldehyde concentration is estimated and calculated from the detector tube measurement values in Table 1 and the actual DNPH method formaldehyde concentration are plotted. As shown in the figure, it was found that a very good correlation was exhibited.
Thus, since the DNPH method formaldehyde concentration can be calculated from the detection tube measurement values and temperature data obtained in Examples 1 to 8 by the correlation equation, the formaldehyde concentration in a house can be easily measured by the detection tube.
[0055]
【The invention's effect】
According to the present invention, the formaldehyde concentration can be easily and quickly evaluated from a house, and the measurement accuracy of the detector tube method can be improved. Therefore, if this method is used, it is possible to hand over a newly built house after confirming that the formaldehyde concentration in the building has been sufficiently reduced, which is extremely useful.
[Brief description of the drawings]
BRIEF DESCRIPTION OF DRAWINGS FIG. 1 is a graph showing measured values with a detector tube and detection sensitivity of acetaldehyde using acetaldehyde concentration and formaldehyde concentration by DNPH method.
FIG. 2 is a graph showing the correlation between acetaldehyde concentration and formaldehyde concentration in a house.
FIG. 3 is a graph showing a correlation between a measured value of formaldehyde concentration by the DNPH method and an estimated value by correction-converted detector tube measurement.

Claims (1)

It is a simple method for measuring the formaldehyde concentration in a house by introducing and measuring the air in the house containing formaldehyde into a detector tube filled with a filler that utilizes the reaction between hydroxylamine phosphate and formaldehyde,
After the mechanical ventilation equipment has been operated for 5 days or more after the completion of the house, the air in the house is introduced into the detector tube, and the measured values obtained from the detector tube are subjected to the DNPH method and the detector tube method under the same conditions. A simple method for measuring formaldehyde concentration in a house, wherein the measurement error of formaldehyde concentration is corrected by subtracting the equivalent amount of acetaldehyde concentration obtained from the correlation equation obtained from the correlation between measured formaldehyde concentration and acetaldehyde concentration measurement value .

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