Gas mixing device, plateau gas supply type breathing apparatus and oxygen supply method

Abstract

The application discloses a gas mixing device and a plateau gas supply type respirator. The gas mixing device comprises a gas bag, wherein an oxygen inlet, an air inlet and a gas flow outlet are arranged on the gas bag, flow adjusting devices are connected to the oxygen inlet and the air inlet, and a gas bag one-way valve is connected to the gas flow outlet. The gas bag has the ability to elastically recover to the original volume. The plateau gas supply type respirator comprises the gas mixing device, a fan, a face mask and an oxygen source, wherein an inhalation inlet and an exhalation outlet are arranged on the face mask, the inhalation inlet is connected to the gas bag one-way valve, and the exhalation outlet is provided with a face mask one-way valve. The gas mixing device mixes breathing gas in the breathing interval, and obtains breathing gas with a natural oxygen partial pressure greater than that of the use place. The gas bag one-way valve is only opened during inhalation, so that the waste of oxygen is avoided, and the oxygen is greatly saved. The application further discloses an oxygen supply method.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of medical devices, in particular to a gas mixing device, a highland gas supply type respirator and an oxygen supply method. BACKGROUND

[0002] The human respiratory process is to dissolve oxygen in the air into the blood and then combine with hemoglobin, and then provide oxygen required for metabolism to all tissues and organs in the body. The solubility of oxygen in the blood is proportional to the oxygen partial pressure.

[0003] The atmospheric pressure in coastal areas is about 100 kiloPascal, and the mole fraction (equal to the volume fraction) of oxygen is 21%, and the mole fraction of nitrogen is 78%, so the partial pressure of oxygen is about 100 kiloPascal x 21% = 21 kiloPascal. After the oxygen is inhaled by a person, part of it is dissolved in the blood, and the oxygen partial pressure in the artery is 11-13 kiloPascal, and the venous blood is about 4-5 kiloPascal. Generally speaking, when the oxygen partial pressure of inhaled gas is lower than 16 kiloPascal, the person will have hypoxia symptoms and become slow in action. Below 6 kiloPascal, the person will start to lose consciousness, and even die.

[0004] The atmospheric pressure in coastal areas is about 100 kiloPascal, and the mole fraction (equal to the volume fraction) of oxygen is 21%, and the mole fraction of nitrogen is 78%, so the partial pressure of oxygen is about 100 kiloPascal x 21% = 21 kiloPascal. After the oxygen is inhaled by a person, part of it is dissolved in the blood, and the oxygen partial pressure in the artery is 11-13 kiloPascal, and the venous blood is about 4-5 kiloPascal. Generally speaking, when the oxygen partial pressure of inhaled gas is lower than 16 kiloPascal, the person will have hypoxia symptoms and become slow in action. Below 6 kiloPascal, the person will start to lose consciousness, and even die.

[0005] In the past, the highland area has adopted a diffused oxygen supply mode to provide oxygen supplement conditions for people living in a room. For example, in the Naqu area, a 20 square meter relatively closed human living room has a room volume of about 70 cubic meters, an oxygen partial pressure of 0.134 ATA, and an oxygen content in the room of 9.38 cubic meters (volume under local atmospheric pressure). If the oxygen partial pressure is adjusted to 0.21 ATA equivalent to the coastal area, 5.32 cubic meters of oxygen needs to be supplemented in the room. Because the room is relatively sealed, many factors will cause the oxygen partial pressure in the room to decrease rapidly due to diffusion to the outside of the room, and if the oxygen partial pressure in the room is to be maintained at 0.21 ATA, oxygen needs to be continuously supplemented into the room. According to statistics, a relatively closed room needs to continuously supplement 2-3 cubic meters of oxygen into the room per hour to maintain the oxygen partial pressure in the room at 0.21 ATA. Such a room needs to supplement 60-75 cubic meters of oxygen into the room day and night to achieve the oxygen partial pressure level equivalent to that in the coastal area.

[0006] Another oxygen increasing method is to use a mask to inhale oxygen, that is, a user wears a mask, and oxygen in an oxygen cylinder is decompressed and introduced into the mask to increase the oxygen partial pressure in the mask, but the existing mask is generally provided with three through holes, one of which is connected with the oxygen cylinder, and the other two through holes are directly communicated with the outside, which are used as the exhaust port of exhalation and the air inlet, so that the mask forms a high-concentration oxygen breathing gas. The human respiratory process is alternating exhalation and inhalation, and statistics show that the average breathing cycle of an adult is 3.7 seconds, of which 1 second is the inhalation process and 2.7 seconds is the exhalation process. The current mask continuously provides oxygen, that is, the user inhales oxygen whether in the inhalation process or in the non-inhalation process. Regardless of the oxygen supply state, the human body can only inhale oxygen in less than 1 second of the inhalation process, and cannot inhale oxygen in the non-inhalation process, even if oxygen is supplied, it cannot be utilized by the human body, so oxygen is wasted.

[0007] Therefore, how to avoid the waste of oxygen as much as possible under the premise of meeting the needs of improving the quality of breathing and realizing the maximum utilization of oxygen is a difficult problem that the person skilled in the art has been trying to overcome. SUMMARY

[0008] The technical problem to be solved by the present application is to provide a gas mixing device to solve the oxygen waste problem caused by high-altitude oxygen supply breathing.

[0009] To solve the above technical problems, the technical scheme adopted by the present application is:

[0010] A gas mixing device, comprising a gas bag, the gas bag is provided with a first gas flow inlet, a second gas flow inlet and a gas flow outlet, the first gas flow inlet is connected with a first flow adjusting device, the second gas flow inlet is connected with a second flow adjusting device, and the gas flow outlet is connected with a one-way valve of the gas bag; the first gas flow inlet is used for introducing oxygen or air, and the second gas flow inlet is used for introducing air or oxygen; the gas bag has elasticity and the ability to restore the original volume.

[0011] Compared with the prior art, the present application has the following technical effects:

[0012] In normal operation, when the gas in the mixing device is sucked by the user, the mixing device is in a negative pressure state relative to the outside, at this time the one-way valve at the gas flow outlet of the mixing device is closed, in the process of the user exhaling, the first gas flow inlet and the second gas flow inlet are simultaneously connected to air and oxygen, and the air and oxygen are fully mixed in the air bag, waiting for the next time the user inhales, the best state of the user inhaling is that the air volume in the air bag plus the air volume in the process of inhaling = the air volume required by the user for one breath, thus, the mixing device is always in a negative pressure state relative to the outside air pressure, ensuring that the one-way valve at the gas flow outlet of the mixing device is only opened when the user inhales, the mixed gas with increased oxygen in the mixing device can make the user breathe the respiratory gas with an oxygen partial pressure of 0.21 ATA, in the process of the user exhaling, the mixing device re-distributes the air, and does not release oxygen outward in the process, and the process is repeated to realize the maximum utilization of oxygen.

[0013] Based on the above technical solution, the application can be further improved as follows.

[0014] Preferably, an air bag expansion device is further arranged, which is used to restore the original volume of the air bag.

[0015] The beneficial effect of the above further scheme is that after the user inhales, the air bag contracts, and in the case that the air bag itself does not have the elasticity to restore the original state, the air bag expansion device can assist the air bag to expand to restore the volume before inhaling, which forms a necessary negative pressure environment in the air bag, so that the one-way valve at the gas flow outlet is closed to avoid the overflow of oxygen.

[0016] Preferably, the air bag expansion device is a spring arranged in the air bag, and two ends of the spring are respectively fixed on the opposite inner surfaces of the air bag.

[0017] The beneficial effect of the above further scheme is that the spring production process is mature and the production cost is low.

[0018] Further, the air bag expansion device further comprises a piston guide rod arranged in the air bag, and the spring is sleeved on the piston guide rod.

[0019] The beneficial effect of the above further scheme is that the spring arranged in the air bag is compressed or expanded in a limited direction, and is not prone to collapse due to the weight of the spring itself.

[0020] Preferably, the air bag expansion device is arranged in the air bag and comprises a first hoop, a second hoop and a plurality of elastic ribs, two ends of each of the plurality of elastic ribs are respectively fixed on the first hoop and the second hoop, forming a lantern-shaped elastic framework, and the air bag is wrapped on the elastic framework.

[0021] The beneficial effect of the further scheme is that after the user inhales, the air bag contracts, and in the case that the air bag itself does not have the resilience to restore to the original state, the elastic framework can assist the air bag to expand to restore to the volume before inhalation, which forms the necessary negative pressure environment inside the air bag, so that the one-way valve at the air outlet is closed to avoid the overflow of oxygen.

[0022] Preferably, a sampling port is further arranged on the air bag for collecting the gas in the air bag for detection.

[0023] The beneficial effect of the further scheme is that sampling and detection are facilitated, the component content of oxygen in the mixed gas is determined, and then whether the oxygen partial pressure meets the requirements is determined.

[0024] A highland gas-mixing breathing apparatus, characterized in that it comprises a face mask, a fan and the gas-mixing device as described above, the face mask is provided with an inhalation port and an exhalation port, the inhalation port is connected with the one-way valve of the air bag, and the exhalation port is provided with a face mask one-way valve; the air outlet of the fan is connected with the first flow regulating device or the second flow regulating device.

[0025] Compared with the prior art, the beneficial effects are as follows: when the user inhales, the mixed breathing gas with an oxygen partial pressure of 0.21 ATA in the gas-mixing device is completely inhaled, and when the user exhales, the exhaled gas is discharged through the exhalation port on the face mask, and the air bag one-way valve is in a closed state, so that the gas-mixing device continuously configures the gas during the exhalation of the user for the next breathing. By adjusting the gas inlet amount per unit time of each gas inlet of the gas-mixing device, the gas amount in the gas-mixing device plus the charging amount during the inhalation process = the required gas amount for one breathing of the user can be achieved when the user inhales next time. Therefore, the gas-mixing device is always in a negative pressure state relative to the external air pressure, which ensures that the air bag one-way valve is only opened when the user inhales, thereby realizing the full use of oxygen and avoiding the waste of oxygen overflow.

[0026] Preferably, the oxygen source comprises an oxygen cylinder and / or an oxygen generator, and the gas outlet of the oxygen source is connected with the second flow regulating device or the first flow regulating device.

[0027] The beneficial effect of the further scheme is that the amount of oxygen carried at one time can be increased, and the ability of continuous oxygen supply can be greatly improved.

[0028] Preferably, the oxygen inlet supplies oxygen at an amount of The amount of oxygen supplied per minute is calculated according to the following formula:

[0029]

[0030] wherein, Q is the air supply per minute of the air inlet, P is the oxygen partial pressure at standard atmospheric pressure, atm P is the standard atmospheric pressure, x P is the atmospheric pressure at the place of use.

[0031] The beneficial effect of the further solution is to ensure that the oxygen content in the gas mixing device corresponds to the oxygen partial pressure in coastal areas.

[0032] Preferably, the air supply per minute of the air inlet Q k is calculated as follows:

[0033]

[0034] Q is the average inhalation per minute of the user, Q k represents the air supply per minute in the atmospheric pressure environment of the place of use, Q is the oxygen supply per minute in the atmospheric pressure environment of the place of use.

[0035] The beneficial effect of the further solution is to ensure that the gas volume in the gas mixing device corresponds to the gas volume required for the user's breathing.

[0036] A highland gas-provision oxygen supply method based on the highland gas-provision respirator described above, the steps are as follows:

[0037] S1, according to the atmospheric pressure P x of the place of use, the average inhalation per minute Q of the individual, calculate the oxygen required to be supplemented per minute when achieving the target oxygen partial pressure at the place of use and the air required to be supplemented per minute Q k ,

[0038] S2, adjust the oxygen supply per minute to adjust the air supply per minute to Q k ;

[0039] S3, wait for the highland gas-provision respirator to run for at least 2 seconds;

[0040] S4, put on the mask and breathe normally. BRIEF DESCRIPTION OF DRAWINGS

[0041] Figure 1 is a structural schematic diagram of the gas mixing device of Example 1;

[0042] Figure 1-1 is a structural schematic diagram of the contraction rod in Example 1;

[0043] Figure 2 is a structural schematic diagram of the gas mixing device of Example 2;

[0044] Figure 3 Structure diagram of piston guide rod in Example 3;

[0045] Figure 4 Structure diagram of highland air supply respirator in Example 4;

[0046] Figure 5 Structure diagram of face mask in Example 4.

[0047] In the drawings, the component names represented by each reference numeral are listed as follows:

[0048] 1, sampling port; 2, air outlet; 3, air pipe; 4, face mask; 4-1, inhalation port; 4-2, exhalation port; 5, air bag one-way valve; 6, oxygen cylinder; 7, air bag; 8, oxygen flow valve; 9, oxygen inlet; 10, air flow valve; 11, air inlet; 12, sealing ring; 13, spring; 13', elastic rib; 13'-1, upper hoop; 13'-2, lower hoop; 14, fan; 15, contraction rod; 15-1, first air flow channel; 15-2, second air flow channel; 15-3, air hole; 15-4, limiting convex ring; 16, piston guide rod; 16-1, first guide part; 16-2, second guide part; 16-3, air hole; 16-4, air bag clamping part. DETAILED DESCRIPTION

[0049] The principles and features of the present application are described below in conjunction with the drawings, and the examples are only used to explain the present application and are not used to limit the scope of the present application.

[0050] Example 1:

[0051] Please refer to Figure 1 , which is a structure diagram of the gas mixing device of the present application. The gas mixing device comprises an air bag 7, a first air inlet (provided as an air inlet 11), a second air inlet (provided as an oxygen inlet 9), an air outlet 2 and a sampling port 1, the air inlet 11 is connected with an air flow valve 10, the oxygen inlet 9 is connected with an oxygen flow valve, and the air flow valve 10 is connected with a fan 14; the air outlet 2 is connected with a one-way valve, and the sampling port 1 is used to collect the gas in the air bag for detection;

[0052] There is also a contraction rod 15, such as Figure 1-1As shown, the shrinkage rod 15 is a cylinder with a first airflow channel 15-1 and a second airflow channel 15-2 respectively opened at both ends along the axial direction. A partition is provided between the first airflow channel 15-1 and the second airflow channel 15-2. The first airflow channel 15-1 is connected to the sampling port 1, and the second airflow channel 15-2 is connected to the oxygen inlet 9. The main body of the shrinkage rod 15 is located inside the airbag. The shrinkage rod 15 has a plurality of vent holes 15-3 radially provided, and the vent holes 15-3 connect the first airflow channel 15-1 and the second airflow channel 15-2. One end with the first airflow channel 15-1 is fixed to the airbag, and the other end with the second airflow channel 15-2 is slidably and airtightly connected to the airbag through a sealing ring 12. The shrinkage rod 15 is also provided with a limiting protrusion ring 15-4 to limit the sliding range of the sealing ring 12. The airbag is equipped with a spring 13, which is fitted onto the retraction rod 15. One end of the spring 13 is fixed to the airbag, and the other end is fixed to the sealing ring 12, so that the airbag has the ability to restore its original volume.

[0053] Example 2:

[0054] like Figure 2 As shown, unlike Embodiment 1, in this embodiment, the airbag expansion device consists of an upper hoop 13'-1, a lower hoop 13'-2, and several elastic ribs 13' inside the airbag. The two ends of the several elastic ribs 13' are respectively fixed to the upper hoop 13'-1 and the lower hoop 13'-2 to form a lantern-shaped elastic skeleton. The airbag is wrapped around the elastic skeleton, thereby enabling the airbag to restore its original volume.

[0055] Example 3:

[0056] like Figure 3 As shown, unlike Embodiment 1, in this embodiment, a piston-type guide rod 16 replaces the contraction rod 15 in Embodiment 1. The piston-type guide rod 16 includes a first guide portion 16-1 and a second guide portion 16-2. The first guide portion 16-1 and the second guide portion 16-2 are fitted together to form a piston-like structure. One end of the first guide portion 16-1 is a sampling port 1, and one end of the second guide portion 16-2 is an oxygen inlet 9. Both the first guide portion 16-1 and the second guide portion 16-2 are provided with air holes 16-3. The piston-type guide rod 16 also has an airbag clamping portion 16-4, and the piston-type guide rod is sealed to the airbag through the airbag clamping portion. The spring is sleeved on the piston-type guide rod.

[0057] Example 4:

[0058] like Figure 4-5As shown, a highland air mixing respirator based on the mixing device described in embodiment 1, further comprising a mask 4 and an oxygen cylinder 6, the outlet of the oxygen cylinder 6 is connected to a pressure reducing valve, the pressure reducing valve is connected to the oxygen inlet 9 of the mixing device, the mask 4 is provided with an inhalation port 4-1 and an exhalation port 4-2, the inhalation port is connected to the airflow outlet 2 of the mixing device through an air tube 3, and the exhalation port 4-2 is connected to a one-way valve. In this embodiment, in order to facilitate operation, the one-way valve 5 at the airflow outlet 2 of the mixing device is moved to the inhalation port near the mask 4, and the flow control valve 8 at the oxygen inlet 9 of the mixing device is moved to the outlet of the pressure reducing valve of the oxygen cylinder 6.

[0059] Assuming that the tidal volume of the user (i.e. the amount of air inhaled per breath) is 500ml, the average breathing rate is 20 times per minute, and the inhalation time is 1s and the exhalation time is 2.7s per breath.

[0060] When the user is breathing normally, 10L of air is needed per minute, which is approximately standard atmospheric pressure, i.e. 101.3kpa, and the oxygen partial pressure is 0.21ATA, so the 10L of air inhaled contains 2.1L of oxygen (at standard atmospheric pressure); in the Naiqiu region of Tibet at an altitude of 4507 meters, the local atmospheric pressure is 58.9kpa, and the oxygen partial pressure is 0.12ATA, so the same 10L of air contains 1.24L of oxygen (at standard atmospheric pressure), and if the user wants to breathe oxygen equivalent to that in the coastal region, 2.1-1.24=0.86L of oxygen (at standard atmospheric pressure) needs to be supplemented, which is equivalent to 0.86L / 0.589=1.46L in the Naiqiu region. The specific calculation formula is as follows:

[0061]

[0062] Wherein, is the oxygen supply per minute in the atmospheric environment of the use site, Q is the average inhalation of the user per minute, is the oxygen partial pressure at standard atmospheric pressure, P atm is the standard atmospheric pressure, P x is the atmospheric pressure of the use site.

[0063] Through the above calculation, it is determined that, in order to obtain the oxygen partial pressure equivalent to that in the coastal area, 1.46L of oxygen needs to be supplemented per minute (in the atmospheric pressure environment of the Naqu area) when the device is used in the Naqu area. Therefore, the oxygen flow valve 8 is first adjusted to control the oxygen flow at 1.46L per minute, and then the air flow valve 10 is adjusted so that the air blower 14 can provide 10-1.46=8.54L of air per minute, because the user needs to breathe 10L of gas per minute. In this way, the air provided by the air blower 14 and the oxygen provided by the oxygen cylinder 6 are mixed in the mixing device 7 according to the above-mentioned ratio, and the air obtained is exactly equivalent to the oxygen partial pressure in the coastal area. The volume of the mixing device 7 is set to 500ml, which is equivalent to the tidal volume of the user. During the previous inhalation process, the gas in the mixing device 7 is completely inhaled, the mixing device 7 contracts, and the user stops inhaling. After that, the one-way valve at the air flow outlet 2 of the mixing device 7 is closed, and the mixing device 7 returns to the original 500ml volume under the action of the spring 13. Therefore, a negative pressure is formed inside the mixing device 7 relative to the outside, and the air and oxygen continuously supplied by the air blower 14 and the oxygen cylinder 6 to the mixing device 7 will be temporarily stored in the mixing device 7 without overflowing, because the user's exhalation time is 2.7s, and during this time, the flow rate of the air blower 14 and the oxygen cylinder 6 is not enough to fill the pressure in the gas bag to be higher than the outside pressure. In the ideal state, when the pressure in the mixing device 7 reaches equilibrium with the outside pressure, it is exactly the beginning of the next inhalation. Therefore, the device can make full use of the oxygen in the oxygen cylinder 6, and the oxygen will not be wasted during the user's exhalation.

[0064] If a 2L oxygen cylinder 6 is set with a working pressure of 15Mpa, it can contain 300L of oxygen at standard atmospheric pressure, and can be used continuously for 348 minutes by a normal adult in an area at an altitude of 4500 meters (atmospheric pressure 58.9kpa, oxygen partial pressure 0.12ATA), and can be used continuously for 434 minutes in an area at an altitude of 3000 meters (atmospheric pressure 67.2kpa, oxygen partial pressure 0.14ATA). The oxygen consumption is only 1 / 70-1 / 50 of the traditional diffused oxygen supply, greatly saving the consumption of oxygen and avoiding waste.

[0065] A highland gas supply method based on the above-mentioned highland gas supply respirator, the steps are as follows:

[0066] S1, according to the atmospheric pressure P of the use site x , the average inhalation volume Q of the individual per minute, calculate the oxygen amount needed to be supplemented per minute to achieve the target oxygen partial pressure in the use site and the air amount needed to be supplemented per minute Q k ,

[0067] S2, adjust the oxygen supply per minute to adjust the air supply per minute to Q k ;

[0068] S3, wait for the high-altitude air supply type respirator to run for at least 2 seconds;

[0069] S4, put on the mask and breathe normally.

[0070] The above only describes the preferred embodiments of the present application and is not intended to limit the present application. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A gas mixing device, characterized by, The airbag has elasticity, and a first air flow inlet, a second air flow inlet and an air flow outlet are arranged on the airbag. The first air flow inlet is connected with a first flow regulating device, the second air flow inlet is connected with a second flow regulating device, and the air flow outlet is connected with an airbag one-way valve. The first air flow inlet is used for inputting oxygen or air, and the second air flow inlet is used for inputting air or oxygen. A sampling port is further arranged on the airbag, and is used for collecting gas in the airbag for detection. An airbag expansion device is further arranged, and is used for restoring the original volume of the airbag. The airbag expansion device comprises a spring and a contraction rod arranged in the airbag. The contraction rod is a cylinder, and first and second air flow channels are arranged on both ends of the contraction rod in the axial direction. A partition plate is arranged between the first and second air flow channels. The first air flow channel is connected with the sampling port, and the second air flow channel is connected with the oxygen inlet. The main body of the contraction rod is arranged in the airbag. A plurality of air holes are radially arranged on the contraction rod, and the air holes are connected with the first and second air flow channels. One end of the first air flow channel is fixed on the airbag, and one end of the second air flow channel is connected with the airbag in a slidable and air-tight manner through a sealing ring. A limiting convex ring is further arranged on the contraction rod, and is used for limiting the sliding range of the sealing ring. The spring is sleeved on the contraction rod, and one end of the spring is fixed on the airbag, and the other end of the spring is fixed on the sealing ring, so that the airbag has the ability to restore the original volume.

2. The gas mixing device of claim 1, wherein The airbag expansion device comprises a spring and a piston guide rod arranged in the airbag.

3. The gas mixing device of claim 2, wherein The airbag expansion device is a lantern-shaped elastic framework arranged in the airbag. The lantern-shaped elastic framework comprises a first hoop, a second hoop and a plurality of elastic rib strips. The two ends of the plurality of elastic rib strips are fixed on the first hoop and the second hoop respectively, so as to form the lantern-shaped elastic framework. The airbag is wrapped on the elastic framework.

4. A high altitude air augmenting breathing apparatus characterized by, The airbag, the fan and the air mixing device according to any one of claims 1-3 are arranged in the face mask. The face mask is provided with an air inlet and an air outlet. The air inlet is connected with the airbag one-way valve, and the air outlet is provided with a face mask one-way valve. The air outlet of the fan is connected with the first flow regulating device or the second flow regulating device.

5. The high altitude air breathing respirator of claim 4, wherein, The oxygen source comprises an oxygen cylinder and / or an oxygen generator. The air outlet of the oxygen source is connected with the second flow regulating device or the first flow regulating device.

6. The high altitude air breathing respirator of claim 5, wherein, Oxygen supply per minute Calculated as follows: The air supply Qk per minute is calculated according to the following formula: wherein, Qk is the air supply amount per minute in the atmospheric pressure environment of the use site, Q is the average inhalation amount per minute of the user, Patm is the oxygen partial pressure under the standard atmospheric pressure, Patm is the standard atmospheric pressure, Px is the atmospheric pressure of the use site, and Qk represents the air supply amount per minute in the atmospheric pressure environment of the use site.

7. A high altitude air supply method, characterized by, The plateau air supply respirator according to any one of claims 4-6 is used according to the following steps: S1. According to the atmospheric pressure Px of the use place and the average inhalation amount Q of the individual per minute, the oxygen supply amount per minute and the air supply amount per minute Qk required for achieving the target oxygen partial pressure in the use place are calculated. Q=QK+QO2. S2, adjust the oxygen supply per minute to adjust the air supply per minute to Qk; S3. Wait for at least 2 seconds for the plateau air supply respirator to run. S4. Wear the face mask and perform normal breathing.

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