RU2509375C2 - Respiratory phantom impactor - Google Patents

Abstract

FIELD: medicine.

SUBSTANCE: respiratory phantom impactor comprises cascade elements placed in a sample bowl built in a body with a pipe fitting attached to an upper part of the body by a threaded connection. Each cascade element, without the last one, consists of a nozzle plate 4, 8, 12, 16, 20, 24, with nozzle holes, a collector plate 6, 10, 14, 18, 22, 26 with a viscous substance coating its surface, and a spacer ring 7, 9, 15, 17, 19, 25, 27; a filter 28 is used as the last cascade element. The seven cascade elements are provided for the gravity sedimentation of aerosols in the respiratory organs. The collector plates 6, 10, 14, 18, 22, 26 are provided for the gravity sedimentation of an aerosol size fraction sedimentary in various parts of the respiratory tract.

EFFECT: assessing the tissue and respiratory distribution of an internal radiation dose after inhalations of the radioactive aerosols.

3 cl, 6 dwg

Description

The invention relates to a device for the dispersed analysis of radioactive aerosols entering the human body with inhaled air, and is intended to simulate the fractional deposition of aerosol particles in the human respiratory tract in order to display the distribution of the expected effective dose of internal exposure to organs and tissues. The device can be used for radiation monitoring of air purity at the enterprises of nuclear energy and industry and in the environment, as well as for assessing the effectiveness of personal protective equipment (PPE) in relation to radioactive aerosols of various dispersion.

The main factors that form the dose of internal exposure during inhalation of radioactive aerosols are the dispersed and radionuclide composition, as well as the types of chemical compounds [1, 2]. Of the known methods for determining the dispersion of aerosols, the most widely used method are multilayer filters and the method of multistage impactors [3, 4]. Using these methods, histograms of the distribution of aerosol particle diameters and the parameters of this distribution are obtained. If the distribution of activity by particle size of the dispersed phase of the aerosol is logarithmically normal, then the main parameters are the activity median aerodynamic diameter (AMAD) and standard geometric deviation. Knowing these parameters, it is possible to estimate the distribution of deposited aerosol particles in the human respiratory tract. However, if the distribution of activity by particle size of the dispersed phase of the aerosol is not logarithmically normal, then to assess the distribution of the expected effective dose of internal exposure to the organs and tissues of the human respiratory tract, it becomes necessary to use a device that simulates the fractional deposition of aerosol particles in each of the sections of the human respiratory tract.

It is known to use a cascade impactor in medicine to determine the effectiveness of using inhaled drug delivery devices [5], however, this device is not intended for sampling radioactive aerosols.

It is known to use the cascade impactor Andersen as a simulator of the human respiratory tract for the deposition of radioactive aerosols [6]. The disadvantages of this device include the actual design, in which it is impossible to quickly analyze the activity of the selected fractions of radioactive aerosols.

The closest in technical essence and the achieved result is a cascade impactor according to the patent of the Russian Federation for invention No. 2239815 [7]. The advantages of this device include ease of use, providing the ability to quickly obtain data, compactness and low cost. The disadvantages of this device include the inability to display the distribution of the expected effective dose of internal exposure during inhalation of radioactive aerosols in cases where the distribution of activity by particle size of the dispersed phase of the aerosol is not logarithmically normal.

The aim of this invention is the creation of an impact phantom of the human respiratory tract, simulating the fractional deposition of aerosol particles in each of the sections of the human respiratory tract and allowing you to quickly evaluate the distribution of the expected effective dose of internal exposure to the tissues and organs of the respiratory tract when inhaled by radioactive aerosols using spectrometric and radiometric devices (regardless of whether the distribution of activity by EPAM dispersed phase of aerosol lognormal).

To achieve this goal, an impact phantom of the human respiratory tract was created containing cascade elements located in a sampling basket placed in the housing, each cascade element (except the last) consisting of a nozzle plate, a collector plate with a viscous substance deposited on its surface and two dividing rings, a filter was used as the last cascade element, a fitting used to select about from closed technological spaces, tight boxes. Inertial deposition of aerosols was carried out on the collector plates of the cascade elements of the impactor-phantom, simulating the fractional deposition of aerosols in the parts of the human respiratory tract. However, the new impactor had a high aerodynamic drag. To overcome this drawback, it was proposed to produce nozzle plates with nozzle openings having a chamfer at the inlet at an angle of 45 °, which ensured a decrease in the aerodynamic drag of the device.

The efficiency of particle deposition ε _i on the collector plate of the i-th cascade element of the impactor-phantom is the ratio of the number of particles of a given aerodynamic diameter deposited on the collector plate of the i-th cascade element to the number of particles of the same diameter in the air stream directed at this cascade element, calculated [8] by the formula (I):

$${\epsilon }_i=N_{\mathrm{one}}/{\mathrm{<figure-callout\; id="2"\; label="N"\; filenames="00000005.png,00000008.png"\; state="\{\{state\}\}">N</figure-callout>}}_2,(\mathrm{one})$$

where N ₁ is the number of particles of a given aerodynamic diameter deposited on the collector plate of the i-th cascade element;

N ₂ - the number of particles of the same diameter, which were in a stream of air directed at a given cascade element.

The aerodynamic diameter corresponding to ε _i = 0.5 is called the effective cascade aerodynamic diameter of separation D ₅₀ (Eng. ECAD - Effective Cut off Aerodynamic Diameter) [9]. His calculation was carried out according to the formula (2):

$$D_{\mathrm{fifty}}=\sqrt{S{t}_{\mathrm{fifty}}}\cdot \sqrt{\frac{9\cdot \mu \cdot W}{C_C\cdot {\rho }_h\cdot V}},(2)$$

where D ₅₀ - effective cascade aerodynamic diameter of separation, microns;

St ₅₀ is the Stokes number corresponding to the aerodynamic diameter of the particle with a deposition efficiency of 50%;

µ is the kinematic viscosity, g / cm · s;

W is the diameter of the nozzle, cm;

ρ _h - the density of aerosol particles, g / cm ³ ;

C _C - Cunningham amendment;

V is the linear velocity of particles in the nozzle hole, cm / s The linear velocity of particles V in the nozzle hole is determined [8] by the formula (3):

$$V=\frac{Q}{\pi \cdot N\cdot {\mathrm{<figure-callout\; id="2"\; label="W"\; filenames="00000005.png,00000008.png"\; state="\{\{state\}\}">W</figure-callout>}}^2/\mathrm{four}},(3)$$

where N is the number of nozzles;

Q - air flow through the impactor, l / min.

Therefore, the desired value of D ₅₀ can be achieved with various combinations of parameters N and W.

Respiratory tract departments are differentiated in accordance with the dosimetric model of the respiratory system of Publication 66 of the ICRP [2], which is formally described as a set of sequentially arranged filters with specific aerosol particle capture efficiencies. The human respiratory tract in Publication 66 of the ICRP is presented in the form of four anatomical departments, with the first, third and fourth departments comprising two sub-departments (FIG. 1):

1. Extrathoracic department (ET) consists of the front of the nasal passage (ET ₁ ), and the rear of the nasal passage (ET ₂ ).

2. Tracheobronchial section (BB), includes the trachea and bronchi.

3. The bronchiolar division (bb), consists of primary bronchioles and terminal bronchioles.

4. The alveolar-interstitial department (AI) consists of respiratory bronchioles and alveoli, etc.

Figure 1 shows the correspondence of the cascade elements of the impact phantom to the departments and subdivisions of the human respiratory tract, allocated in accordance with Publication 66 of the ICRP, indicating the effective cascade aerodynamic diameters of the separation D _{50 of the} cascade elements (with an air flow rate of 20 l / min):

- on the collector plate of the first cascade element there is an inertial deposition of the size fraction of aerosols deposited in the front of the nasal passage (D ₅₀ = 9.0 μm);

- on the collector plate of the second cascade element there is an inertial deposition of the size fraction of aerosols deposited in the back of the nasal passage (D ₅₀ = 5.8 μm);

- on the collector plate of the third cascade element there is an inertial deposition of the size fraction of aerosols deposited in the trachea and bronchi (D ₅₀ = 4.7 μm);

- on the collector plate of the fourth cascade element, inertial deposition of the size fraction of aerosols deposited in the primary bronchioles occurs (D ₅₀ = 3.3 μm);

- on the collector plate of the fifth cascade element, inertial deposition of the size fraction of aerosols deposited in terminal bronchioles occurs (D ₅₀ = 1.1 μm);

- on the collector plate of the sixth cascade element, inertial deposition of the size fraction of aerosols deposited in respiratory bronchioles occurs (D ₅₀ = 0.6 μm);

- on the seventh cascade element, which is used as a filter, the size fraction of aerosols is deposited, which in the human respiratory tract settles in the alveoli (D ₅₀ less than 0.6 μm).

Cascading elements of the impactor-phantom are placed in the sampling basket (figure 2), which ensures the speed of replacement of cascading elements. The use of collector plates in the design of thin flat disks, in the center of which there is a circular hole for air flow to the next cascade element or filter, allows these collector plates to be placed directly in standard spectrometric and radiometric devices when analyzing the activity of aerosol fractions. The nozzle plates (FIG. 3, FIG. 4) are flat disks with nozzle openings evenly distributed over several concentric circles (or one circle). Mnogosopelnost promotes uniform distribution of deposited aerosol particles on the surface of the collector plates of all cascade elements. In addition, the diameter of the nozzle hole on the nozzle plate does not exceed the thickness of the nozzle plate, which increases the selectivity of each cascade element to the size of the deposited aerosol particles.

The device also allows you to measure the dispersed composition of the aerosol, which was previously passed through a respiratory protective equipment. By determining the change in the disperse composition and the total number of aerosols during the passage of air flow through the PPE, it is possible to evaluate the effectiveness of the PPE in relation to radioactive aerosols of different dispersion.

Figure 1 shows the correspondence of the cascade elements of the impact phantom to the departments and subdivisions of the human respiratory tract, allocated in accordance with Publication 66 of the ICRP [2], indicating the effective cascade aerodynamic diameters of the separation of the cascade elements (D ₅₀ ); figure 2 shows the layout of the sampling basket of the device; figure 3 - nozzle plate with nozzle holes distributed over three concentric circles; figure 4 - nozzle plate with nozzle holes distributed along one circumference; figure 5 is a device in section; figure 6 - connection diagram of the device.

The proposed device (figure 2 and figure 5) consists of the lower part of the housing 1, the upper part of the housing 2, a sampling basket 3 and cascade elements. The first cascade element of the impactor-phantom consists of a nozzle plate 4, a separation ring 5, a collector plate 6, on which inertial deposition of the size fraction of aerosols deposited in the front of the nasal passage of a person (subdivision ET _{1 of the} extra-thoracic ET section in the dosimetric model of Publication 66 ICRP [ 2]) and a dividing ring 7, which separates the collector plate 6 of the first cascade element from the nozzle plate 8 of the second cascade element. The second cascade element consists of a nozzle plate 8, a dividing ring 9, a collector plate 10, on which inertial deposition of the size fraction of aerosols deposited in the posterior part of the nasal passage of the person (ET ₂ subunit of the extra-thoracic ET section in the dosimetric model of Publication 66 of the ICRC [2]) and a dividing ring 11, which separates the collector plate 10 of the second cascade element from the nozzle plate 12 of the third cascade element of the impactor phantom. The third cascade element consists of a nozzle plate 12, a separation ring 13, a collector plate 14, on which inertial deposition of the size fraction of aerosols deposited in the trachea and bronchi (tracheobronchial BB section in the dosimetric model of Publication 66 ICRP [2]) and the separation ring 15, separating the collector plate 14 of the third cascade element from the nozzle plate 16 of the fourth cascade element. The fourth cascade element consists of a nozzle plate 16, a dividing ring 17, a collector plate 18, on which inertial deposition of the aerosol size fraction deposited in the primary bronchioles (bronchiolar section bb in the dosimetric model of Publication 66 of the ICRP [2]) and the separation ring 19 separating the collector plate 18 of the fourth cascade element from the nozzle plate 20 of the fifth cascade element. The fifth cascade element consists of a nozzle plate 20, a separation ring 21, a collector plate 22, on which the size fraction of aerosols deposited in the terminal bronchioles is deposited (bronchiolar section bb in the dosimetric model of Publication 66 of the ICRP [2]) and a separation ring 23 separating the collector the plate 22 of the fifth cascade element from the nozzle plate 24 of the sixth cascade element. The sixth cascade element consists of a nozzle plate 24, a dividing ring 25, a collector plate 26, on which inertial deposition of the aerosol size fraction deposited in the respiratory bronchioles (alveolar-interstitial department AI) and a dividing ring 27 separating the collector plate 26 of the sixth cascade element the seventh cascade element (filter) 28, on which the deposition of the size fraction of aerosols deposited in the alveoli occurs (alveolar-interstitial section AI in dosimetric th model of Publication 66 of the ICRP [2]). The sampling basket 3 is a hollow cylinder, open at the top and having a cross at the bottom for fixing the filter and other cascade elements. It has two recesses on the side walls for ease of installation of cascading elements. A fitting 29 is connected to the upper part of the housing 2 by means of a threaded connection, both parts of the housing are connected by fixing screws 30, gaskets 31, 32 are used for sealing. In the lower part of the housing 1 there is a fitting 33 for connecting a flow inducer.

The operation of the device.

The preparation of the device for operation is carried out in the following order: the sampling basket 3 is assembled in accordance with the scheme of FIG. 2, having previously applied a viscous substance to the surface of the collector plates 6, 10, 14, 18, 22, 26; place the gasket 32 in the lower part of the housing 1; then the assembled sampling basket 3 is placed in the lower part of the housing 1, which is connected to the upper part of the housing 2 by means of fixing screws 30, a gasket 31 is used for sealing. A flow inductor 34 equipped with a flowmeter 35 is connected to the fitting 33 in the lower part of the housing, as shown in device connection diagram (Fig.6).

The selection of a radioactive aerosol is carried out using a flow rate stimulator that provides a volumetric flow rate that does not exceed acceptable limits (20 l / min), which corresponds to the average person’s breathing rate in accordance with the “Radiation Safety Standards” (NRB-99/2009) SanPiN 2.6. 1.2523-09, paragraph 4.2 [1].

The impactor phantom is installed at the sampling location, then the flow inducer 34 is turned on, the air containing aerosol particles enters the device through the nozzle 29 and is formed into the stream with the specified spatial-velocity parameters. Once inside the device, the aerosol particles move along with the air flow at a linear speed, determined by the size and number of nozzle holes of the nozzle plate 4. A sharp change in the direction of flow after the nozzle holes of the nozzle plate 4 pass through the first cascade element leads to the inertia the most massive particles do not have time to change the direction of their motion and are deposited in a viscous substance covering the collector plate 6 of the first cascade element, when that on the collecting plate 6 of the first cascade element occurs inertial deposition of aerosol size fraction, precipitating in front of the human nasal stroke (subdivision ET ₁ to ET extrathoracic card dosimetry model ICRP Publication 66 [2]). Further, the air flows through the nozzle openings of the nozzle plate 8 enter the second cascade element, where they again change direction and are directed to the hole located in the center of the collector plate 10, while inertial deposition of the aerosol size fraction deposited on the surface of the collector plate 10 of the second cascade element in the posterior part of the nasal passage of a person (ET ₂ extra-thoracic ET unit in the dosimetric model of Publication 66 of the ICRP [2]). Then, the air flows through the nozzle openings of the nozzle plate 12 enter the third cascade element and, again, sharply change direction towards the hole in the center of the collector plate 14, while the size fraction of aerosols sedimenting in the trachea and bronchi is deposited on the collector plate 14 of the third cascade element. (tracheobronchial section of the explosive in the dosimetric model of Publication 66 of the ICRP [2]). Further, the air flows through the nozzle openings of the nozzle plate 16 enter the fourth cascade element, where they sharply change direction and are directed to the hole in the center of the collector plate 18, while inertial deposition of the aerosol size fraction deposited in the primary bronchioles occurs on the collector plate 18 of the fourth cascade element (bronchiolar bb in the dosimetric model of Publication 66 of the ICRP [2]). Then, air flows through the nozzle openings of the nozzle plate 20 enter the fifth cascade element, sharply change direction towards the hole in the center of the collector plate 22, while the size fraction of aerosols deposited in the terminal bronchioles is deposited on the collector plate 22 of the fifth cascade element (bronchiolar bb in the dosimetric model of Publication 66 of the ICRP [2]). After that, the air flows through the accelerating holes of the nozzle plate 24 enter the sixth cascade element, where they are connected in one stream at the center of the collector plate 26, while inertial deposition of the aerosol size fraction deposited in the respiratory bronchioles (alveolar) occurs on the surface of the collector plate 26 of the sixth cascade element. -interstitial department of AI in the dosimetric model of Publication 66 of the ICRP [2]). After the collector plate of the sixth cascade element, the air stream is directed to the filter 28, the aerosol particles remaining in the air stream are deposited on the filter 28, so the size fraction of aerosols is deposited, which in the human respiratory tract settles in the alveoli (alveolar-interstitial department AI in the dosimetric model of Publication 66 MKRZ [2]), after which the air flow leaves through the fitting 33 in the lower part of the device. Sampling is carried out depending on the nature of the problem to be solved for 0.5-3 hours, after which the flow driver 34 is turned off. The impactor phantom 36 is disassembled: the upper part of the housing 2 is detached, the basket 3 with cascading elements is removed or replaced with a new one. Cascading elements are carefully removed from the basket. The activity accumulated on the collector plates and the filter is measured using spectrometric and radiometric instruments.

Example 1

Estimation of the distribution of the expected effective dose of internal exposure in the respiratory tract during inhalation of a radioactive aerosol containing plutonium dioxide ²³⁹ PuO ₂ .

Depending on the rate of transfer of the radionuclide from the lungs to the blood, the chemical compounds of the radionuclides located on aerosol particles are divided into three types: M — slowly soluble compounds, P — compounds soluble at an intermediate speed, and B — rapidly soluble compounds [4]. ²³⁹ PuO ₂ in terms of absorption rate is of type M [1], which is subsequently taken into account when determining the effective dose of internal exposure. To assess the distribution of the expected effective dose of internal radiation in the respiratory tract of a person with inhalation of radioactive aerosol ²³⁹ PuO _2, proceed as follows: the sampling basket 3 is assembled in accordance with the scheme in Fig. 2, having previously been applied to the surfaces of the collector plates 6, 10, 14 , 18, 22, 26 viscous substance (TsIATIM-221, GOST 9433-80). The diameter of the nozzle holes and the thickness of the nozzle plates 4, 8, 12, 16, 20, 24 are selected taking into account the fact that the air velocity is set at 20 l / min: the first nozzle plate 4 with a thickness of 3.0 mm has 24 nozzle holes with a diameter 2.8 mm, the second nozzle plate 8 with a thickness of 2.0 mm has 24 nozzle holes with a diameter of 2.0 mm, the third nozzle plate 12 with a thickness of 2.0 mm has 24 nozzle holes with a diameter of 1.8 mm, the fourth nozzle plate 16 with a thickness of 2.0 mm has 24 nozzle holes with a diameter of 1.4 mm, the fifth nozzle plate the tire 20 with a thickness of 1.0 mm has 24 nozzle holes with a diameter of 0.7 mm, the sixth nozzle plate 24 with a thickness of 1.0 mm has 12 nozzle holes with a diameter of 0.5 mm. The location of the nozzle holes for the first five nozzle plates is shown in figure 3, and for the sixth nozzle plate in figure 4. Then place the gasket 32 in the lower part of the housing; place the assembled sampling basket 3 in the lower part of the housing 1, which is connected to the upper part of the housing 2 by means of fixing screws 30, gasket 31 is used for sealing (Fig. 5). The impactor phantom is installed at the sampling location, then with the help of a flow driver 34 equipped with a flow meter 35, the volumetric flow rate of the air flow through the device is set to 20 l / min (Fig.6). Sampling is carried out within 3 hours. At the end of the selection, the impactor phantom 36 is disassembled and the sampling basket 3 is removed. The collector plates are removed without disturbing the lubricated surfaces. To measure activity, the collector plates are mounted alternately in the radiometer holder and activity is measured. Then, the values of the expected effective dose of internal exposure during inhalation are calculated for each department of the respiratory tract. For this, the activity value of the aerosol fraction deposited on the surface of this collector plate is multiplied by a dose coefficient depending on the nuclide composition, solubility class, and dispersion of the aerosol [10]. As a result, the distribution of the expected effective dose of internal exposure during inhalation of the organs and tissues of the human respiratory tract is obtained. The results are listed in table 1.

Table 1 Estimation of the distribution of the expected effective dose of internal exposure to tissues and organs of the respiratory tract with inhalation of a radioactive aerosol containing ²³⁹ PuO ₂ No. Respiratory tract Activity, Bq Dose coefficient, Sv / Bk Expected effective dose of internal exposure, μSv one Front of the nasal passage (ET ₁ ) 0.1 4.7 · 10 ^-6 0.47 2 Back of the nasal passage (ET ₂ ) eleven 2 · 10 ^-4 2.2 · 10 ³ 3 Trachea and bronchi (BB) 4.3 3.6 · 10 ^-3 1.610 ⁴ four Primary Bronchioles (bb) 6.7 3 · 10 ^-3 2.0 · 10 ⁴ 5 Terminal Bronchioles (bb) 1.3 3 · 10 ^-3 3.9 · 10 ³ 6 Respiratory Bronchioles (AI) 0.5 1.3 · 10 ^-3 6.510 ² 7 Alveoli (AI) 2 1.3 · 10 ^-3 2.6 · 10 ³

Based on the data obtained, we can conclude that the greatest value of the expected effective dose falls on the bronchial bb (primary bronchioles).

Example 2

Evaluation of the distribution of the expected effective dose of internal exposure in the respiratory tract upon inhalation of a radioactive aerosol containing polonium dioxide ²¹⁰ PoO ₂ .

To assess the distribution of the expected effective dose of internal exposure in the respiratory tract upon inhalation of a radioactive aerosol containing polonium dioxide ²¹⁰ PoO ₂ (absorption type: P), proceed as follows: make the sampling basket 3 in accordance with the scheme in FIG. 2, having previously applied on the surface of the collector plates 6, 10, 14, 18, 22, 26 a viscous substance (TsIATIM-221, GOST 9433-80). The diameter of the nozzle holes and the thickness of the nozzle plates (Figs. 3, 4) are selected taking into account that the air velocity is set at 20 l / min. Further, the preparation of the device for operation is carried out in the same way as in example 1. The impactor phantom is installed at the sampling location, then with the help of a flow inducer 34 equipped with a flow meter 35, the volumetric flow rate of air flow through the device is set to 20 l / min (FIG. .6). Sampling is carried out within one hour. At the end of the selection, the impactor phantom 36 is disassembled and the sampling basket 3 is removed. The collector plates are removed without disturbing the lubricated surfaces. To measure activity, the collector plates are mounted alternately in the radiometer holder and activity is measured. Then, the values of the expected effective dose of internal exposure during inhalation are calculated for each department of the respiratory tract. For this, the activity value of the aerosol fraction deposited on the surface of a given collector plate is multiplied by a dose coefficient depending on the nuclide composition, solubility class, and dispersion of the aerosol [10]. As a result, the distribution of the expected effective dose of internal exposure during inhalation of the organs and tissues of the human respiratory tract is obtained. The results are listed in table 2.

table 2 Estimation of the distribution of the expected effective dose of internal exposure to tissues and organs of the respiratory tract during inhalation of a radioactive aerosol containing ²¹⁰ PoO ₂ No. Respiratory tract Activity, Bq Dose coefficient, Sv / Bk Expected effective dose of internal exposure, μSv one Front of the nasal passage (ET ₁ ) 0.2 1.85 · 10 ^-5 3,7 2 Back of the nasal passage (ET ₂ ) eleven 4.310 ^-7 4.7 3 Trachea and bronchi (BB) 4,5 1.2 · 10 ^-5 0.5 four Primary Bronchioles (bb) 6.4 1.6 · 10 ^-5 10 ^-2 5 Terminal Bronchioles (bb) 4.6 1.6 · 10 ^-5 73.6 6 Respiratory Bronchioles (AI) 0.5 3.2 · 10 ^-6 1,6 7 Alveoli (AI) 0.7 3.2 · 10 ^-6 2.2

Based on the data obtained, it can be concluded that the greatest value of the expected effective dose falls on the bronchial bb department (terminal bronchioles).

Thus, it has been shown that the goal has been achieved: an impact phantom of the human respiratory tract has been created, which simulates the fractional deposition of aerosol particles in each part of the human respiratory tract and allows using the spectrometric and radiometric instruments to quickly evaluate the distribution of the expected effective dose of internal exposure to tissues and respiratory tract with inhalation of radioactive aerosols, regardless of whether the distribution of a ciency size of the dispersed phase of aerosol particles lognormal.

Information sources

1. Norms of radiation safety (NRB-99/2009): Hygienic standards. - M.: Center for Sanitary and Epidemiological Regulation of Hygienic Certification and Expertise of the Ministry of Health of Russia, 2009. - 73 p.

2. International Commission on Radiological Protection. Human respiratory tract model for radiological protection. ICRP Publication 66 // Ann. ICRP, 1994. Vol. 24, Nos. 1-3. - 300 p.

3. MU 2.6.1.26-2000 Dosimetric control of professional internal exposure. General requirements. - 2000. - 53 p.

4. Budyka A.K., Borisov N.B. Fiber filters to control air pollution. - M .: Publishing House, 2008 .-- 359 p.

5. RU 2175556 C2, 11/10/2001.

6. Papastefanou C. Radioactive Aerosols (Volume 12 in series "Radioactivity in the Environment"). - Argyll: Elsevier, 2008-186 p.

7. RU 2239815 C1, 10.11.2004.

8. Kwon S.B., Kim M.C., Lee K.W. Effects of jet configuration on the performance of multi-nozzle impactors // Journal of Aerosol Science. - V.33, Issue 6, 2002. - P.859-869.

9. Raist P. Aerosols, an introduction to theory. - M.: Mir, 1987 .-- 278 p.

10. The ICRP Database of Dose Coefficients: Worker and Members of the Public [Electronic resource, CD-ROM]. - Elsevier Science Ltd, 2001.

Claims (3)

1. Impact phantom of the human respiratory tract, containing cascade elements located in a sampling basket located in the housing, to the top of which a threaded connection is connected, each cascade element, except the last one, consists of a nozzle plate with nozzle holes, a collector plate with a viscous substance and a spacer ring deposited on its surface, a filter is used as the last cascade element, characterized in that the impactor phantom contains there are cascade elements installed with the possibility of inertial deposition of aerosols to simulate fractional deposition of aerosols in the human respiratory tract, wherein: the collector plate of the first cascade element is configured to provide inertial deposition of the size fraction of aerosols deposited in front of the nasal passage, the collector plate of the second cascade element - inertial deposition of the size fraction of aerosols deposited in the back of the nasal passage, count lecture plate of the third cascade element — deposition of the dimensional fraction of aerosols deposited in the trachea and bronchi; on the collector plate of the fourth cascade element — deposition of the dimensional fraction of aerosols deposited in the primary bronchioles; collector plate of the fifth cascade element — deposition of the dimensional fraction of aerosol aerosols; the collector plate of the sixth cascade element is the deposition of the size fraction of aerosols deposited in the respiratory bronchioles, and the seventh cascade The th element, which is used as a filter, is configured to provide deposition of the size fraction of aerosols deposited in the alveoli. 2. The impactor phantom according to claim 1, characterized in that the nozzle plates of the first five cascade elements are flat disks with nozzle holes uniformly distributed over three concentric circles, and the nozzle plate of the sixth cascade element is a flat disk with nozzle holes uniformly distributed along one circle. 3. The impactor phantom according to claim 2, characterized in that the nozzle holes have a chamfer at the entrance at an angle of 45 °.

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