This standard specifies the test methods for the anti-gas performance and physical properties of filter-type gas mask canisters. This standard is applicable to the performance testing and evaluation of filter-type gas mask canisters; other related products can also refer to it. GB/T 2892-1995 Test method for the performance of filter-type gas mask canisters GB/T2892-1995 Standard download decompression password: www.bzxz.net

National Standard of the People's Republic of China
Performance test methods for canister of filter type respirator
1 Subject content and scope of application
GB/T2892—1995
Replaces GB2892.1~2892.12---82
This standard specifies the test methods for the anti-gas performance and physical properties of filter type respirator canisters (hereinafter referred to as canisters). This standard is applicable to the performance testing and evaluation of filter type respirator canisters; other related products can also refer to it. 2 Reference standards
GB2890 General technical conditions for filter type respirators GB7702.10 General method for determining the effective protection time of coal-based granular activated carbon 3 Technical content
3.1. General method for the anti-poison time test of the gas filter canister 3.1.1 Instruments
a. DX-1 type dynamic adsorption gas analysis device See Figure 1:
Figure 1 DX-1 type dynamic adsorption analysis device diagram
Connecting bottle or flow meter
1--Air purifier; 2-humidification device; 3-hygrometer; 4--drying tube; 5--gas flow meter 6--evaporator or boat bottle (Figure 2); 7 water bath; 8---mixer; 9--toxic gas cylinder; 10-orifice flow meter; 11---gas filter canister; 12-indicator bottle (Figure 3); 13---waste gas absorption tank; 14 absorption bottle (Figure 4) Approved by the State Administration of Technical Supervision on June 28, 1995 and implemented on January 1, 1996
GB/T 2892—1995
Figure 2 Evaporator
Figure 3 Indicator bottle
Balance: accuracy 0.01g;
Stopwatch: division value 0.1s.
3.1.2 Test conditions
Test temperature: 17~~30℃;
Relative humidity of air: 50%±3%;
Figure 4 Absorption bottle
GB/T 2892—1995
c. Gas flow rate through the gas filter canister: 30±0.3L/min; d. For the concentration of the poisoning agent vapor of the mixed gas, please refer to Table 5 and Table 6 of GB2890. 3.1.3 Test steps
3.1.3.1 Test preparation
a. The gas flow meter shall be calibrated once every 3 months and the use point shall be calibrated once a month; b. DX-1 test device According to the process shown in Figure 1, all parts are installed vertically on the instrument board, and the parts are connected with high-quality rubber hoses;
The installed instrument should be checked for air tightness. During the inspection, a pressure of 13kPa is created in the instrument. Within 1 minute, the pressure drops by no more than 270Pa, which means it is airtight; the humidity of the gas is controlled by a hygrometer, and the calculation method is in accordance with Appendix C of GB7702.10; d.
e: Control the gas flow rate according to the flowmeter calibration curve; f. Control the test temperature according to the temperature of the dry bulb in the hygrometer. 3.1.3.2 Test operation
Open the compressed air (or negative pressure exhaust) piston, and use the piston (K1) to adjust the total air flow; use the pistons (K2 and K3) to adjust the humidity of the air flow; use the piston (K9) to adjust the gas flow of the gas filter. Slowly open the piston (K4) and the piston on the evaporator (or cylinder), adjust the height difference of the liquid column of the flowmeter (K5) to the position where the concentration has been calibrated in advance, and use a stopwatch to record the test time. Method for determining the concentration of the poisoning agent in the mixed gas: a. Gravimetric method
Use a balance to weigh the weight of the evaporator before and after the test (accurate to 0.05g). The concentration of the poisoning agent in the mixed gas is calculated according to formula (1): c=
Where: c—
Concentration of the poisoning agent in the mixed gas, mg/L; weight of the evaporator before the test, g;
m2—weight of the evaporator after the test, g;
t-evaporator opening time, min;
V—air flow, L/min.
b. Chemical absorption method
m2×1000
（1）
Use two absorption bottles, each filled with 25mL of absorption liquid, and connect them in series to the DX-1 device (see Figure 1). Open the piston (K6) and let the mixed gas pass through the absorption bottle at a rate of 50 to 100mL/min. Use the lower bottle and a volumetric tube or flowmeter to measure the ventilation volume. The volume of gas passing through the absorption bottle in each test is between 1.5 and 3.0L. At the end of the test, close the piston (K6), remove the absorption bottle, transfer the absorption liquid into a conical flask, and use the chemical analysis method to determine the poisoning dose of the absorption liquid. Calculate the concentration of the poisoning agent vapor in the mixed gas based on the volume of water discharged from the lower bottle. 3.1.3.3 Determination of the penetration of poisonous agent vapor into the canister - Indicator method: 20 mL of indicator liquid is placed in the indicator bottle, connected to the DX-1 test device (see Figure 1), and passed at a rate of 1.0 ± 0.1 mL/min. When a trace amount of poisonous agent penetrates the canister, the test endpoint is determined by the color change of the indicator; it can also be determined by an instrument. 3.1.3.4 After the test, close (K4) and continue to purge the instrument with clean air for 20 minutes. 3.1.4 Test results
The concentration of poisonous agent in each test should be within the specified range to be valid. The anti-poisoning time measured at the test concentration is converted into the anti-poisoning time at the standard concentration according to formula (2):
In the formula: t - anti-poisoning time of the canister, min; t} - anti-poisoning time at the test concentration, min; C1 - poisonous agent concentration in the mixed gas during the test, mg/L; (2)
The specified standard concentration, mg/L.
3.1.5 Test report
Include the following contents:
Sample name or code;
Test environment conditions;
Test method;
d. Test results;
e. Tester's signature;
f. Test date.
GB/T 2892—1995
3.2 Test method for the anti-toxic time of gas filter canister against hydrocyanic acid vapor 3.2.1 Instruments and reagents
3.2.1.1 Instruments
a. DX-1 dynamic adsorption gas analysis device, see Figure 1, b. Balance: accuracy 0.01g,
c. Stopwatch: graduation value 0.1 s.
3.2.1.2 Reagents
Hydrocyanic acid should meet the following technical requirements: Appearance is colorless and transparent liquid. In the presence of colloidal sulfur and ferric sulfate, a slight opalescence is allowed; content is not less than 97.5%; hydrogen sulfide content does not exceed 0.2%; stabilizer sulfuric acid content is 0.3%~0.5%; b.
Silver nitrate standard solution c(AgNO)=0.02mol/L; sodium hydroxide standard solution c(NaOH)=0.1mol/L; potassium iodide ; Analytically pure;
Ammonia water: analytically pure;
Quantitative analysis indicator: weigh 2g potassium iodide and dissolve it in 40mL ammonia water and 60mL water; Indicator for hydrogen cyanide vapor permeation canister: weigh 0.5g benzidine hydrochloride and dissolve it in 250mL hot water. After cooling, add 10mL 3% copper acetate solution and 40mL 5% acetic acid solution to prepare the indicator, which is stored in a brown bottle. The storage time shall not exceed 15 days. If the indicator turns blue-black during use, it should be replaced. 3.2.2 Test conditions
According to 3.1.2.
3.2.3 Test steps
3.2.3.1 Test preparation
According to 3.1.3.1.
3.2.3.2 Test operation
According to 3.1.3.2. The generation and concentration of poisonous gas are determined as follows: a. Hydrocyanic acid vapor is generated using a boat-shaped bottle, which is placed in an ice-water bath at 0°C; b. The concentration of hydrocyanic acid vapor in the mixed gas is determined using gravimetric analysis as the standard, and chemical absorption analysis as a control. When conducting chemical absorption analysis, 50ml of sodium hydroxide standard solution [c(NaOH)=0.1mol/L] is used as the absorption liquid. After absorption, 1mL of quantitative indicator is added, and silver nitrate standard solution [c(AgNO,)=0.02mol/L] is dripped until the solution becomes lightly turbid as the end point. The concentration of hydrocyanic acid vapor in the mixed gas is calculated according to formula (3): 54.05 × cV
wherein; c-
concentration of hydrocyanic acid vapor in the mixed gas, mg/L, molar concentration of silver nitrate standard solution, mol/L; amount of silver nitrate standard solution, ml;
(3)
GB/T 2892—1995
V--volume of the mixed gas passing through the absorption bottle, L; 54.05--volume of the mixed gas passing through the absorption bottle with 1.00mL silver nitrate standard solution [c(AgNO.)1.000mol/L] is equivalent to the mass of hydrocyanic acid expressed in milligrams.
3.2.3.3 Indication method for hydrocyanic acid vapor to pass through the canister: Pour 20mL of water into the indicator bottle, add 3-4 drops of indicator, and pass through the indicator bottle at a speed of 1L/min. When a trace amount of hydrocyanic acid vapor passes through, the indicator turns blue, which is the end point. 3.2.4 Test results
According to 3.1.4.
3.2.5 Test report
According to 3.1.5.
3.3 Test method for the anti-toxic time of the canister against cyanogen chloride vapor 3.3.1 Instruments and reagents
3.3.1.1 Instruments
DX-1 dynamic adsorption gas analysis device, see Figure 1; a.
A set of automatic potentiometric titrators.
3.3.1.2 Reagents
Cyanogen chloride is a colorless transparent liquid (slightly yellowish is allowed) with a content of not less than 96%; hydrocyanic acid content is not more than 4%; chlorine a.
Hydrogen chlorine content is not more than 0.01%; no free chlorine; stabilizer content is 0.3% to 1.0%. b.
Silver nitrate standard solution c(AgNO.)=0.02mol/L; potassium thiocyanate standard solution c(KSCN)=0.02mol/L; 5% sodium hydroxide solution;
1% phenolic acid solution;
2% perchlorate solution;
Nitric acid: analytical grade;
Sodium bicarbonate: analytical grade;
Nitrogen benzene: analytical grade;
Iodine standard solution c1/212)=0.05mol/L; c(1/2I,)=0. 01 mol/L;
Arsenic trioxide standard solution: c(1/4As2O.）=0.02mol/L; 1% starch solution;
Cyanogen chloride permeation indicator solution: Preparation of stock solution: Add 40g sodium bicarbonate to 700mL water, heat to dissolve, add 250mL nitrogen benzene and 50mL of 0.5mol/L iodine solution at room temperature, and leave it for 5 days as stock solution. During the storage process, it should be checked to ensure that there is excess free iodine. The inspection method is to add 2~～3mL stock solution and 2mL of 1% starch solution in a test tube, and a blue color should be generated at this time. Preparation of permeation indicator: Take 100mL stock solution, add 20mL of 1% starch solution and dilute with water to 900～950mL, and drop arsenic trioxide [c(1/4As2O3）=0.02mol/L] standard solution until the blue color disappears. Use iodine standard solution [c(1/212) 0.02mol/L] to back-titrate until it turns blue, then accurately add iodine standard solution [c(1/2I2)=0.01mol/L15.0mL and add water to 1000mL. This solution is the indicator solution used. After the indicator is prepared, it should not be left for more than 8h. n. Saturated aqueous solution of ammonium ferric sulfate.
3.3.2 Test conditions
According to 3.1.2.
3.3.3 Test steps
3.3.3.1 Test preparation
According to 3.1.3.1.
3.3.3.2 Test operation
According to 3.1.3.2.
Cyanogen chloride, using a steel cylinder filled with cyanogen chloride to generate. GB/T2892—1995
The concentration of cyanogen chloride vapor in mixed gas is determined by chemical absorption analysis. Use 50mL of 5% sodium hydroxide solution for absorption. The analysis of cyanogen chloride concentration in the absorption solution allows the use of two methods: automatic potentiometric titration or chemical titration (hand drop). a. Automatic potentiometric titration analysis
Put the absorption solution and washing solution in a 200mL flask and add a few drops of phenolphthalein. Add concentrated nitric acid under stirring until the red color fades, add 20 drops of concentrated nitric acid, and add 8 drops of solution evenly for titration. Check the automatic potentiometric titrator to make it in working state, use the silver electrode as the indicator electrode, the special calomel electrode of saturated potassium chloride as the reference electrode (saturated nitric acid solution as the bridge) and insert it into the solution to be titrated. Install it according to the instrument requirements, and adjust the zero potential at 700mV, the end point potential to -270mV (i.e. 430mV), start electromagnetic stirring, and observe the initial potential first (generally around -100mV). Then use silver nitrate [c(AgNO) = 0.2mol/L for titration. When the endpoint is reached, the titration stops automatically and the volume of the consumed silver nitrate solution (V) is read. For blank titration, take 50mL of 5% sodium hydroxide solution and add 30mL of water in a 200mL beaker, add 1 drop of phenolphthalein indicator, add concentrated nitric acid while stirring to make the red color fade, add 20 drops of concentrated nitric acid and 8 drops of phenolphthalein solution, titrate according to the above method, and read the volume of the consumed silver nitrate solution (V).
The concentration of cyanogen chloride in the mixed gas is calculated according to formula (4): 61. 5 X cr(Vi - Vo)
Where: c——the concentration of cyanogen chloride in the mixed gas, mg/L; Ci-the molar concentration of the silver nitrate standard solution, mol/L; Vi——the amount of the silver nitrate standard solution, mL; V. Blank titration silver nitrate standard solution, mL; V—Volume of mixed gas passing through the absorption bottle, L
61.5——Mass of cyanogen chloride in milligrams equivalent to 1.00mL silver nitrate standard solution [c (AgNO3) = 1.000mol/L].
b. Chemical titration analysis
Put the absorption solution and washing solution in a 300mL conical flask, add a few drops of phenol anhydride indicator solution to the conical flask, add concentrated nitric acid under stirring until the red color fades, and add excess concentrated nitric acid 1.0mL. Drop 20ml of silver nitrate standard solution [c = (AgNO3) = 0.02mol/L], and add 3 to 5 drops of ammonium ferric sulfate indicator solution. After shaking evenly, titrate with potassium thiosulfate standard solution [c (KSCN) 0.02mol/L] until the solution turns light blood color.
Blank titration method: take 50mL of 5% sodium hydroxide solution in a conical flask, add 100mL of water, add 2~3 drops of phenolic acid solution, and neutralize with concentrated nitric acid until the red color fades. Add 1.0mL of concentrated nitric acid, 20mL of silver nitrate standard solution [Lc(AgNO.）=0.02mol/L], and 3~5mL of ammonium ferric sulfate indicator solution. After shaking, titrate with potassium thiocyanate standard solution [c(KSCN)=0.02mol/L] until it turns light blood color. Then calculate the blank titration volume (V.) of potassium thiocyanate. V. = 20 V
Where: V'-
The amount of potassium thiocyanate standard solution used during blank titration, mL. The concentration of cyanogen chloride in the mixed gas is calculated according to formula (6): 61. 5 × Ec,V1 - (c2V2 + c2V.)]c
Wherein: c—the concentration of cyanogen chloride in the mixed gas, mg/L; V
the volume of potassium thiocyanate blank titration solution, mL; C2
the molar concentration of potassium thiocyanate standard solution, mol/L; V2—the amount of potassium thiocyanate standard solution used, mL; 122
the volume of mixed gas passing through the absorption bottle, L.
GB/T 2892
3.3.3.3 Indication method for hydrogen chloride vapor passing through the gas filter canister 1995
Put 20mL of indicator liquid in the indicator bottle. When the blue color of the indicator liquid disappears, it means that the cyanogen chloride vapor has passed through the gas filter canister. 3.3.4 Test results
According to the provisions of Article 3.1.4.
3.3.5 Test report
According to 3.1.5.
3.4 ​​Test method for the anti-toxic time of benzene vapor in the canister 3.4.1 Instruments and reagents
3.4.1.1 Instruments
DX-1 dynamic adsorption gas analysis device, see Figure 1; a.
b. Balance: accuracy 0.01g;
Stopwatch: graduation value 0.1s.
3.4.1.2 Reagents
a. Benzene: analytical grade;
Sulfuric acid: analytical grade,
Sodium nitrite: analytical grade, dried at 105~110℃; c.
Indicator: weigh 2g of dry sodium nitrite and dissolve it in 100mL of sulfuric acid, for use only on the same day. d.
3.4.2 Test conditions
According to Article 3.1.2.
3.4.3 Test steps
3.4.3.1 Test preparation
According to Article 3.1.3.1.
3.4.3.2 Test operation
According to Article 3.1.3.2, the generation and concentration of poisonous gas are as follows: a.
The test evaporator (boat-shaped bottle) generates benzene vapor, and the evaporator is placed in a constant temperature water bath; b. The concentration of benzene vapor in the mixed gas is determined by weight method; the determination method of benzene vapor passing through the gas filter canister is to put 20mL indicator in the indicator bottle, and when a trace amount of benzene vapor passes through the gas filter canister c.
, the indicator changes from colorless to yellow, which means the test is terminated. 3.4.4 Test results
According to Article 3.1.4.
3.4.5 Test report
According to 3.1.5.
3.5 Test method for the protection time of gas filter canister against chlorine gas 3.5.1 Instruments and reagents
3.5.1.1 Instruments
DX-1 dynamic adsorption gas analysis device, see Figure 1; balance: accuracy 0.01g;
stopwatch: graduation value 0.1g.
3.5.1.2 Reagents
Liquid chlorine, for industrial use;
4% and 0.1% potassium iodide solutions, potassium iodide is analytical grade; b.4
Sodium thiosulfate standard solution [c(Na2S,O,)=0.02 mol/L];123
GB/T 2892-1995
d. 0.5% starch solution, starch is analytical grade; indicator for chlorine gas permeation canister: weigh 0.1g potassium iodide, dissolve in 100mL water, and store in a brown bottle. e.
3.5.2 Test conditions
According to 3.1.2.
3.5.3 Test steps
3.5.3.1 Test preparation
According to 3.1.3.1.
3.5.3.2 Test operation
According to 3.1.3.2, the generation and concentration of toxic gas are determined as follows: a. Use chlorine gas cylinders for gas supply;
b. The concentration of chlorine in the mixed gas is determined by chemical absorption analysis method. Use 50ml of 4% potassium iodide solution for absorption. After absorption, use sodium thiosulfate standard solution [Lc (Na2S, O) = 0.02mol/L] to titrate the absorption solution until it turns light yellow. Then add 3-5mL of 0.5% starch solution and continue titrating until the blue color of the solution disappears. The calculation formula is as follows: 35. 5 × cV
Concentration of chlorine in the mixed gas, mol/L;
Where: c——
Molar concentration of sodium thiosulfate standard solution, mol/L;-Amount of sodium thiosulfate standard solution, mL; V,
-Volume of mixed gas passing through the absorption bottle, L; (7)
is the mass of chlorine in milligrams equivalent to 1.00mL sodium thiosulfate standard solution [c(NazS,O3)-1.000mol/L].
Indication method for chlorine gas permeation through the canister: Add 20mL indicator and 3-4mL of 0.5% starch solution into the indicator bottle. When a trace of chlorine gas permeates through the canister, the indicator changes from colorless to light blue, which is the end point. 3.5.4 Test results
According to 3.1.4.
3.5.5 Test report
According to 3.1.5.
3.6 Test method for the anti-toxic time of the canister against ammonia and nitrogen 3.6.1 Instruments and reagents
3.6.1.1 Instruments
DX-1 dynamic adsorption gas analysis device, see Figure 1; a.
Balance: accuracy 0.01g,
Stopwatch: graduation value 0.1s.
3.6.1.2 Reagents
Liquid ammonia;
Sulfuric acid standard solution [c(1/2H,SO)=0.02mol/L]; sodium hydroxide standard solution [c(NaOH) 0.02mol/L]; d. 1% phenolic indicator.
3.6.2 Test conditions
According to 3.1.2.
3.6.3 Test steps
3.6.3.1 Test preparation
According to 3.1.3.1.
3.6.3.2 Test operation
GB/T 2892—1995
According to 3.1.3.2, in which the generation and concentration of toxic gas are determined as follows; a. Liquid ammonia in steel cylinders is used for gas supply;
b. The concentration of nitrogen in the mixed gas was determined by chemical absorption analysis. 25.0 mL of sulfuric acid standard solution [c(H2SO4) = 0.02 mol/L1 was diluted with water to 50 ml as the absorption solution. After absorption, methyl orange was used as the indicator and sodium hydroxide standard solution [c(NaOH) = 0.1 mol/L] was used to titrate the absorption solution until yellow was the end point. The calculation formula is as follows (8): 17.03 × (V2
— V)Gi
Where: c--
concentration of ammonia in the mixed gas flow, mg/L;
amount of sodium hydroxide standard solution, mL;
-amount of sulfuric acid standard solution, mL;
volume of the mixed gas passing through the absorption bottle, L; V
C:---molar concentration of sulfuric acid standard solution and sodium hydroxide standard solution, mol/L; (8)
17.03——the mass of ammonia in milligrams equivalent to 1.00mL sulfuric acid standard solution [c(1/2H2SO.)=1.000mol/L] Indication method of nitrogen permeation through the gas filter: Add 20mL of water to the indicator bottle and add 2 to 3 drops of phenolic acid indicator. When a trace amount of c.www.bzxz.net
ammonia permeates the gas filter, the indicator turns red, which is the end point. 3.6.4 Test results
According to 3.1.4.
3.6.5 Test report
According to Article 3.1.5.
3.7 Test method for the anti-toxic time of the gas filter canister against hydrogen sulfide 3.7.1 Instruments and reagents
3.7.1.1 Instruments
DX-1 dynamic adsorption gas analysis device, see Figure 1; balance: accuracy 0.01g;
stopwatch: graduation value 0.1s.
3. 7. 1. 2
Sulfuric acid: for industrial use;
Sodium sulfide: for industrial use;
Glacial acetic acid: for analytical use;
Potassium iodide standard solution [c(1/2I,)=0.02mol/L]; Potassium permanganate standard solution [c(1/5KMnO4)=0.01mol/L]; Sodium thiosulfate standard solution [c(Na2S,3)=0.02mol/L]; Sulfuric acid solution [c(1/2H2SO,)=5mol/L]; 2% zinc acetate solution Weigh 2g zinc acetate and 1mL glacial acetic acid, use a 100mL volumetric flask, and prepare 100mL aqueous solution; Preparation of the indicator for hydrogen sulfide permeation canister Take 4mL potassium permanganate standard solution [c(1/5KMnO,)=0.01mol/1]i
and 20 mL sulfuric acid solution [c(1/2H2SO4)=5mol/L], make up 100 mL aqueous solution. 3.7.2 Test conditions
According to 3.1.2.
3.7.3 Test steps
3.7.3.1 Test preparation
According to 3.1.3.1.
3.7.3.2 Test operation
GB/T2892—1995
Perform according to Article 3.1.3.2, in which the generation and concentration of poisonous gas are determined as follows: a. The concentration of hydrogen sulfide in the mixed gas flow is determined by absorbing it with 50mL of 2% zinc acetate solution. After absorption, add 20.0mL of iodine standard solution [c(1/212)=0.02mol/L] and titrate it with sodium thiosulfate standard solution [c(Na2SO3）=0.02mol/L]. When the titrated solution turns light yellow, add 3-4mL of 5% starch solution and continue titrating until the blue color disappears as the end point. The concentration of hydrogen sulfide in the mixed gas is calculated according to formula (9):
17. 1 × (Vz - V,)cl
where c is the concentration of hydrogen sulfide in the mixed gas, mg/L, V, - the amount of sodium thiosulfate standard solution, mL; V is the amount of iodine standard solution, mL;
Ci - the molar concentration of sodium thiosulfate standard solution and iodine standard solution, mol/L; V - the volume of the mixed gas passing through the absorption bottle, L; 17. 1 -
the mass of hydrogen sulfide in milligrams equivalent to 1.00mL of iodine standard solution [c (1/212) = 1.000mol/L]. (9)
Indication method for hydrogen sulfide permeating the gas filter: Inject 20mL of indicator into the bottle. When a trace amount of hydrogen sulfide permeates the gas filter, the indicator changes from pink to colorless, which is the end point. 3.7.4 Test results
According to Article 3.1.4.
3.7.5 Test report
According to Article 3.1.5.
3.8 Test method for the anti-poisoning time of the gas filter canister against sulfur dioxide gas 3.8.1 Instruments and reagents
3.8.1.1 Instruments
DX-1 dynamic adsorption gas analysis device, see Figure 1; a.
Balance: accuracy 0.01g;
Stopwatch: graduation value 0.1s.
3.8.1.2 Reagents
Sulfuric acid: for industrial use;
Sodium sulfite: for industrial use;
Iodine standard solution [c(1/2Iz)=0.2mol/L]; sodium thiosulfate standard solution [c (Na2S,O,) = 0.02mol/L]; potassium permanganate standard solution [c (1/5KMnO) = 0.01mol/L]ei
f. 0.5% starch solution.
3.8.2 Test conditions
According to 3.1.2.
3.8.3 Test steps
3.8.3.1 Test preparation
According to 3.1.3.1.
3.8.3.2 Test operation
According to 3.1.3.2, the generation and concentration of poisonous gas are determined as follows: a. Use liquid sulfur dioxide in a cylinder, or use the generation method to prepare sulfur dioxide; b. The concentration of sulfur dioxide in the mixed gas is determined by absorption with 50mL of iodine standard solution [c (1/212) = 0.02mol/L]. After absorption, the excess iodine is titrated with sodium thiosulfate standard solution [c (NazS, O3) = 0.02mol/L]. When the solution turns light yellow, 4-5mL of 0.5% starch indicator is added. The titration is continued until the blue color of the solution disappears. The concentration is calculated according to formula (10): 126
In the formula; c-
GB/T 2892—1995
32. 1 X (Vic)
Sulfur dioxide concentration in the mixed gas, mg/L; -Amount of iodine standard solution, mL;
Molar concentration of iodine standard solution, mol/L; -Amount of sodium thiosulfate standard solution, mL; Molar concentration of sodium thiosulfate standard solution, mal/L; Volume of mixed gas passing through the absorption bottle, L; V2c22
The mass of sulfur dioxide in milligrams equivalent to 1.00mL iodine standard solution [c(1/2I2)=1.000mol/L]. The indication method of sulfur dioxide passing through the gas filter canister is to add 20mL of water and half a drop (about 0.03mL) of potassium permanganate standard solution [c(1/2KMnO,)=0.01mol/L] to the indicator bottle. When a trace amount of sulfur dioxide passes through the gas filter canister, the indicator liquid changes from pink to colorless, which is the end point.
3.8.4 Test results
According to Article 3.1.4.
3.8.5 Test report
According to Article 3.1.5.
3.9 Test method for the anti-poisoning time of the gas filter canister against carbon dioxide gas 3.9.1 Instruments and reagents
3.9.1.1 Instruments
DX-2 dynamic adsorption gas analysis device, see Figure 5; K5
· Carbon dioxide
Figure 5DX-2 dynamic adsorption gas analysis device Figure 1-Air purifier; 2-Capillary air flow meter, 3-Mixer: 4-Humidity regulator, 5--Hygrometer: 6-Orifice air Air flow meter; 7-gas filter: 8-respirator 9-buffer: 10-capillary air flow meter; 11-infrared gas analyzer; 12-capillary air flow meter; 13-drying meter; 14-infrared gas analyzer Infrared gas analyzer analysis range: 0~1×10-2, 1 unit, 0~1×10-4 (or 0~1×10-3) 1 unit, b
respirator: pulse frequency 21~24 times/min, 1 unit; c.
d. Stopwatch: graduation value 0.1s.
3.9.1.2 Reagents
Sulfuric acid: industrial use;
Formic acid: analytical grade.
Test conditions
Test temperature: 17～30℃,
Relative humidity in air flow: 50%±3%;
GB/T2892—1995
The pulsating air flow through the canister is 30±0.5L/min; the pulsating air flow frequency is 21～24 times/min;
The volume concentration of carbon monoxide in the mixed gas is 0.5%. 3.9.3 Test steps
3.9.3.1 Test preparation
According to 3.1.3.1.
3.9.3.2 Test operation
a. This method uses industrial carbon monoxide gas, which can also occur spontaneously. b. First, connect the respirator (8), then open the compressed air piston to allow air to enter the filter. Use the piston (K2) and flowmeter (2) to control the flow of carbon monoxide, so that clean air and carbon monoxide merge in the concentric sleeve and then enter the mixer (3). Open the bypass piston to allow the mixed gas to flow at a rate of 0.5L/min through the flowmeter (12) and the dryer (13) into the infrared gas analyzer (14), and measure the concentration of carbon monoxide in the mixed gas. The mixed gas is humidified by the humidifier (4), and the humidity is measured by the hygrometer (5). Then, it enters the gas filter canister (7) to be tested through the flowmeter (6). The exhaust gas is discharged through the respirator (8), and part of the exhaust gas enters the infrared gas analyzer (11) at a flow rate of 0.5L/min through the buffer (9) and the flowmeter (10). The concentration of carbon monoxide in the exhaust gas is measured. When the concentration reaches 5×10-5, it is the end point. c. After the test, purge the test system with clean air for 20 minutes. 3.9.4 Test results
According to Article 3.1.4.
3.9.5 Test report
According to Article 3.1.5.
3.10 Test method for the anti-toxic time of the gas filter canister against mercury vapor 3.10.1 Instruments and reagents
3.10.1.1 Instruments
a. DX-3 type dynamic adsorption gas analysis device, see Figure 6; K2
Figure 6 DX-3 type dynamic adsorption gas analysis device Figure 1 Fixed spiral clamp; 2-· Air purifier; .-- Humidity regulator 4-- Humidity meter; 5.- Orifice plate gas flowmeter; 6--- Evaporator; ·-- Constant temperature meter; 8· Thermometer; 9 Gas filter canister; 10- Mercury vapor absorber; 11 Fixed spiral clamp; 12--- Indicator tube vacuum bottle;1 Instrument
DX-2 dynamic adsorption gas analysis device, see Figure 5; K5
· Carbon oxide
Figure 5DX-2 dynamic adsorption gas analysis device Figure 1-Air purifier; 2-Capillary air flow meter, 3-Mixer: 4-Humidity regulator, 5--Hygrometer: 6-Orifice air flow meter; 7-Gas filter: 8-Respirator 9-Buffer: 10-Capillary air flow meter; 11-Infrared gas analyzer; 12-Capillary air flow meter; 13-Drying meter; 14-Infrared gas analyzer Infrared gas analyzer analysis range: 0~1×10-2, 1 unit, 0~1×10-4 (or 0~1×10-3) 1 unit, b
Respirator: Pulse frequency 21~24 times/min, 1 unit; c.
d. Stopwatch: graduation value 0.1s.
3.9.1.2 Reagents
Sulfuric acid: industrial use;
Formic acid: analytical grade.
Test conditions
Test temperature: 17-30℃,
Relative humidity in air flow: 50%±3%;
GB/T2892-1995
The pulsating air flow through the gas filter canister is 30±0.5L/min; the pulsating air flow frequency is 21-24 times/min;
The volume concentration of carbon monoxide in the mixed gas is 0.5%. 3.9.3 Test steps
3.9.3.1 Test preparation
According to 3.1.3.1.
3.9.3.2 Test operation
a. This method uses industrial carbon monoxide gas, which can also occur on its own. b. First, connect the respirator (8), then open the compressed air piston to allow air to enter the filter. Use the piston (K2) and flowmeter (2) to control the flow of carbon monoxide, so that clean air and carbon monoxide merge in the concentric sleeve and then enter the mixer (3). Open the bypass piston to allow the mixed gas to flow at a rate of 0.5L/min through the flowmeter (12) and the dryer (13) into the infrared gas analyzer (14), and measure the concentration of carbon monoxide in the mixed gas. The mixed gas is humidified by the humidifier (4), and the humidity is measured by the hygrometer (5). Then, it enters the gas filter canister (7) to be tested through the flowmeter (6). The exhaust gas is discharged through the respirator (8), and part of the exhaust gas enters the infrared gas analyzer (11) at a flow rate of 0.5L/min through the buffer (9) and the flowmeter (10). The concentration of carbon monoxide in the exhaust gas is measured. When the concentration reaches 5×10-5, it is the end point. c. After the test, purge the test system with clean air for 20 minutes. 3.9.4 Test results
According to Article 3.1.4.
3.9.5 Test report
According to Article 3.1.5.
3.10 Test method for the anti-toxic time of the gas filter canister against mercury vapor 3.10.1 Instruments and reagents
3.10.1.1 Instruments
a. DX-3 type dynamic adsorption gas analysis device, see Figure 6; K2
Figure 6 DX-3 type dynamic adsorption gas analysis device Figure 1 Fixed spiral clamp; 2-· Air purifier; .-- Humidity regulator 4-- Humidity meter; 5.- Orifice plate gas flowmeter; 6--- Evaporator; ·-- Constant temperature meter; 8· Thermometer; 9 Gas filter canister; 10- Mercury vapor absorber; 11 Fixed spiral clamp; 12--- Indicator tube vacuum bottle;1 Instrument
DX-2 dynamic adsorption gas analysis device, see Figure 5; K5
· Carbon oxide
Figure 5DX-2 dynamic adsorption gas analysis device Figure 1-Air purifier; 2-Capillary air flow meter, 3-Mixer: 4-Humidity regulator, 5--Hygrometer: 6-Orifice air flow meter; 7-Gas filter: 8-Respirator 9-Buffer: 10-Capillary air flow meter; 11-Infrared gas analyzer; 12-Capillary air flow meter; 13-Drying meter; 14-Infrared gas analyzer Infrared gas analyzer analysis range: 0~1×10-2, 1 unit, 0~1×10-4 (or 0~1×10-3) 1 unit, b
Respirator: Pulse frequency 21~24 times/min, 1 unit; c.
d. Stopwatch: graduation value 0.1s.
3.9.1.2 Reagents
Sulfuric acid: industrial use;
Formic acid: analytical grade.
Test conditions
Test temperature: 17-30℃,
Relative humidity in air flow: 50%±3%;
GB/T2892-1995
The pulsating air flow through the gas filter canister is 30±0.5L/min; the pulsating air flow frequency is 21-24 times/min;
The volume concentration of carbon monoxide in the mixed gas is 0.5%. 3.9.3 Test steps
3.9.3.1 Test preparation
According to 3.1.3.1.
3.9.3.2 Test operation
a. This method uses industrial carbon monoxide gas, which can also occur on its own. b. First, connect the respirator (8), then open the compressed air piston to allow air to enter the filter. Use the piston (K2) and flowmeter (2) to control the flow of carbon monoxide, so that clean air and carbon monoxide merge in the concentric sleeve and then enter the mixer (3). Open the bypass piston to allow the mixed gas to flow at a rate of 0.5L/min through the flowmeter (12) and the dryer (13) into the infrared gas analyzer (14), and measure the concentration of carbon monoxide in the mixed gas. The mixed gas is humidified by the humidifier (4), and the humidity is measured by the hygrometer (5). Then, it enters the gas filter canister (7) to be tested through the flowmeter (6). The exhaust gas is discharged through the respirator (8), and part of the exhaust gas enters the infrared gas analyzer (11) at a flow rate of 0.5L/min through the buffer (9) and the flowmeter (10). The concentration of carbon monoxide in the exhaust gas is measured. When the concentration reaches 5×10-5, it is the end point. c. After the test, purge the test system with clean air for 20 minutes. 3.9.4 Test results
According to Article 3.1.4.
3.9.5 Test report
According to Article 3.1.5.
3.10 Test method for the anti-toxic time of the gas filter canister against mercury vapor 3.10.1 Instruments and reagents
3.10.1.1 Instruments
a. DX-3 type dynamic adsorption gas analysis device, see Figure 6; K2
Figure 6 DX-3 type dynamic adsorption gas analysis device Figure 1 Fixed spiral clamp; 2-· Air purifier; .-- Humidity regulator 4-- Humidity meter; 5.- Orifice plate gas flowmeter; 6--- Evaporator; ·-- Constant temperature meter; 8· Thermometer; 9 Gas filter canister; 10- Mercury vapor absorber; 11 Fixed spiral clamp; 12--- Indicator tube vacuum bottle;
Tip: This standard content only shows part of the intercepted content of the complete standard. If you need the complete standard, please go to the top to download the complete standard document for free.