GB 16210-1996 Hygienic standard for nickel and its inorganic compounds in workplace air
Some standard content:
National Standard of the People's Republic of China
Nickel and its inorganic compounds in the air of the workplace
Health standard
Health standard for nickel and itsinorganic compounds in the air of the workplace1Subject content and scope of application
GB16210-1996
This standard specifies the maximum allowable concentration of nickel and its inorganic compounds in the air of the workplace and the monitoring and inspection methods. This standard applies to the mining, beneficiation and smelting of nickel ore, as well as various operations involving the production and use of nickel and its inorganic compounds. It is not applicable to operations involving contact with carbonyl nickel.
2Health requirements
The maximum allowable concentration of nickel and its inorganic compounds in the air of the workplace: 1 mg/m3 (calculated as Ni) for metallic nickel and sparingly soluble nickel compounds; 0.5 mg/m2 (calculated as Ni) for soluble nickel compounds. 3Monitoring and inspection methods
The monitoring and inspection methods of this standard adopt flame atomic absorption spectrometry or catalytic pulse polarography, see Appendix A (supplement) and Appendix B (supplement).
4 Supervision and Implementation
Health supervision agencies at all levels are responsible for the implementation of this standard. Approved by the State Bureau of Technical Supervision on April 3, 1996 and implemented on September 1, 1996
A1 Principle
GB16210-1996
Appendix A
Flame Atomic Absorption Spectrometry
(Supplement)
Nickel and its compounds in the air are collected on the filter material, and after being digested with nitric acid-perchloric acid, the nickel content is determined by acetylene-air flame atomic absorption spectrometry at a wavelength of 232.0nm.
A2 Instruments
A2.1 Sampling clip.
Filter material: microporous filter membrane, pore size 0.8μm, diameter 40mm. A2.2
A2.3 Vacuum pump.
Flowmeter, 0～10L/min.
Erlenmeyer flask or tall beaker, 50mL.
Ceramic crucible cover, 35cm in diameter.
Test tube with stopper, 10mL.
A2.8 Electric hot plate or electric sand bath.
A2.9 Atomic absorption spectrophotometer, equipped with acetylene-air flame burner and nickel hollow cathode lamp.
A3 Reagents
Deionized water: water with a specific resistance greater than 500kQ·cm obtained by passing through an ion exchange resin column, or water obtained by redistillation using an all-glass distiller. Perchloric acid, p201.67g/mL, high purity, A3.2
Nitric acid, p20-1.42g/mL, high purity.
Perchloric acid (A3.2)-nitric acid (A3.3), 1+9 mixed digestion solution. A3.4bZxz.net
A3.5 Nitric acid, 1+99.
A3.6 Nickel standard solution: Weigh 0.1000g nickel powder (spectrally pure), dissolve in a small amount of nitric acid (A3.3), heat and evaporate until almost dry, transfer the residue to a 100mL volumetric flask with nitric acid (A3.5), and dilute to scale. This solution is 1mL-1.0mgNi; dilute with nitric acid (A3.5) to 1mL-10μgNi standard solution before use.
A4 Sampling
Install the microporous filter membrane (A2.2) in the sampling clip (A2.1), and extract 50L of air sample at a speed of 5L/min. A5 Analysis steps
A5.1 Control experiment: Use the unsampled microporous filter membrane (A2.2) as two blank controls according to the sample processing method. A5.2 Sample treatment: Place the microporous filter membrane in a conical flask, add 5mL perchloric acid-nitric acid (A3.4), cover with a porcelain cover, place on a hot plate for heating and digestion, and keep the temperature at about 200°C. When the solution is colorless and transparent, remove the crucible cover, and when the digestion solution is basically evaporated, remove the conical flask, cool it, add 10mL nitric acid (A3.5) to dissolve the residue, and the solution is used for determination. A5.3 Drawing of standard curve: Take 6 10mL colorimetric tubes and prepare standard tubes according to Table A1. 452
Standard solution (A3.6), ml
Nitric acid (A3.5), ml
Nickel content?ug/ml.
GB 16210-1996
Preparation of nickel standard tube
Adjust the flame atomic absorption spectrophotometer to the optimal operating conditions, and measure the standard tubes respectively at a wavelength of 232.0nm with acetylene-air flame (lean flame), and draw a standard curve. A5.4 Determination: Use the same instrument operating conditions as A5.3 to measure the treated samples. For every 10 samples measured, calibrate the measurement results once with a standard solution of medium concentration, record the absorbance value, and after subtracting the absorbance value of the blank control from the sample absorbance value, find out the nickel content in the sample from the standard curve.
A6 Calculation
A6.1 Calculate the volume of the collected air sample under standard conditions according to formula (A1): V.-Vx
273×t
Where: V.
the sample volume under standard conditions, l.;
V—the volume of the collected air sample, L;
1——temperature, ℃;
atmospheric pressure, kPa.
A6.2 Calculate the nickel concentration in the air according to formula (A2): X-
Wherein: X-the nickel concentration in the air, mg/m~; (---the nickel content in the sample, μg/mL; V.-the sampling volume converted to standard conditions, L. A7 Explanation
(A1)
A7.1 The detection limit of this method is 0.01μg/mL, the sensitivity is 0.12μg/mL, and the measurement range is 0-5μg/mL. The coefficient of variation is 2.6% (3ug/ml).
A7.2 The average sampling efficiency of this method is 99%. During the sampling process, pollution must be prevented. Filter membranes cannot be installed in nickel production sites. Sampling tools such as sampling clamps and tweezers must be kept clean. During the sampling process and during transportation and storage after sampling, dust on the filter membrane must be prevented from falling off. A7.3 After sampling, fold the sampled microporous filter membrane inwards and be careful to package it without loss for long-term storage. A7.4 Influence on measurement Factors that affect determination: The digestion temperature must be controlled below 200℃. If the temperature is too high, the recovery rate will be low. If the temperature is too low, the digestion speed will be slow, and the sample measurement time will be extended.
A7.5 Interference and removal of coexisting substances: 100ppmA13+, Ca2+, Cd2+, Co2+, Cr3+, Fe3+, Mn4+, Mos+, Pb2+, Sn2+, Zn*+ do not interfere with the determination of this method. However, try to use a narrow instrument slit when measuring. A7.6 If using a measuring If the dust filter is used instead of the microporous filter for sampling, 10 mL of percyanic acid-nitric acid (A3.4) should be added during digestion, and if necessary, an appropriate amount of digestion solution should be added until the digestion is complete. 1+4 perchloric acid-nitric acid mixed digestion solution can also be used instead of perchloric acid-nitric acid (A3.4) to accelerate digestion, but good ventilation should be maintained.
A7.7 After sample treatment, if there is white precipitate in the solution, it can be centrifuged or left overnight. 453
B1 Principle
GB 16210—1996
Appendix B
Catalytic pulse polarography
(Supplement)
Aerial nickel is collected on a microporous filter membrane. After being digested with nitric acid and perchloric acid, a small amount of diacetyl is added to the NH,CI-NH,OH-sulfosalicylic acid base solution at a pH of about 9 to produce a sensitive adsorption catalytic wave for nickel. The wave height can be used to determine the nickel content. The peak potential of the nickel wave is -1.0V; the diamond wave follows the nickel wave, and the peak potential is -1.13V. The detection limit of this method is 1×10-°g/mLNi. B2 Instrument
B 2.1 Pulse polarograph (dropping mercury electrode as cathode). B2.2 Anode, micro silver-mercury electrode.
B2.3 Dust sampler, 0~～6L/min. B2.4 Temperature-controlled electric heating plate.
B2.5 Teflon high-type cup, 25mL. B2.6 Microporous filter membrane, pore size 0.8um.
Electrolytic cell, 5～10mL small beaker.
B2.8 Stoppered colorimetric tube, 10mL.
B3 Reagents
B3.11:9 perchloric acid (superior grade)-nitric acid (high purity) mixed digestion solution. B3.2 Double distilled water: distilled water is double distilled through alkaline [Ba(OH),] potassium permanganate. B3.33% nitric acid (high purity).
B3.42mol/l. ammonium chloride solution (superior grade). B3.52mol/L sulfosalicylic acid solution (analytical grade). B3.6 Nitrogen water, high grade.
B3.71:1 hydrochloric acid (high grade).
B3.80.5mg/ml Fe3+ solution (analytical grade). B3.91% butanone ethanol solution (analytical grade). B3.1026% anhydrous sodium sulfite solution (analytical grade). B3.11 Nickel standard solution: weigh 0.1000g nickel powder (spectrally pure) is dissolved in 5mL 1:1 nitric acid. After heating and dissolving, the residual liquid is transferred to a 100mL volumetric flask with 3% nitric acid and diluted to the scale. This solution 1mL = 1mgNi. Before use, dilute it with 3% nitric acid to a standard solution of 1mL = 0.lug nickel.
B4 Sampling
Put the microporous filter in the sampling clip and extract 25L of air at a speed of 5L/min. B5 Analysis steps
B5.1 Sample treatment: Place the sample filter membrane in a polytetrafluoroethylene tall cup, add 5mL of 1:9 mixed digestion solution, place it on a hot plate at about 110℃ and digest until the residual liquid is less than 1.0ml., then heat it to 140℃ and continue digesting until it is almost dry, remove it and add 0.5mL of 1:1 hydrochloric acid to dissolve the sample, use 454
0—1996
GB 16210
5ml. water to transfer the sample solution into a 10mL colorimetric tube, and the solution is used for determination. Use the unsampled microporous filter membrane to treat it according to the above operation as a blank control. B5.2 Preparation of standard tubes
Take 7 25mL polytetrafluoroethylene tall cups and prepare standard tubes according to Table B1. Table B1
Preparation of nickel standard tube
Apply standard solution.ml
Nickel content ·ug
Put the high cup on the hot plate and heat it. When the solution is basically evaporated, take it down. Add 0.5ml.1:1 hydrochloric acid to dissolve the sample. Use 5mL water to transfer the solution into a 10ml. colorimetric tube.
Add 1 drop of Fe3+ solution and 0.5mL sulfosalicylic acid solution to the standard tube and sample tube respectively. Adjust the solution to bright yellow with ammonia water, then add 1 drop, add 0.5mL ammonium chloride solution, 2mL anhydrous sodium sulfite solution, add 0.05ml, diacetyl solution, and add water to the 10mL mark. Shake well, let it stand for 15min, and then measure it on the machine respectively. B5.3 Determination
B5.3.1 Determination of standard tube: Set the starting potential of the instrument to 0.85V, set the conventional derivative switch to derivative, measure the peak height of nickel (mm), subtract the blank, and draw a standard curve. B5.3.2 Determination of sample: Determine the peak height of the sample solution under the above conditions, subtract the peak height of the blank filter solution, and check the standard curve to obtain the nickel content.
B6 Calculation
Formula: X
Nickel concentration in air, mg/m;
(Nickel content in sample solution after subtracting blank, ug; V.——Converted to sampling volume under standard conditions, L.B7 Notes
B7.1 When using the standard curve method for quantification, it is necessary to use a nickel standard solution of a specified concentration to adjust the machine before each work.B7.2 A large amount of iron can be masked with sulfosalicylic acid and will not interfere with the determination of nickel.B7.3 When the cobalt content is high, it affects the back foot of the nickel wave, so this method uses the front foot for quantification. (B1)
B7. 4 In 10mL solution, 10 times the amount of Cd2+, As+, 20 times the amount of Cu2+, Cr3+, A13+, Pb2+, 200 times the amount of Mg2+, and Ca\ do not interfere with the determination of nickel when they coexist. However, when Ca2+ exceeds 40μg/mL, the peak potential of nickel can be moved forward. B7.5 pH value has an effect on the wave height of nickel. When the pH value is equal to 8 or 10, the wave height decreases significantly, and the optimal pH value is 8.5~9.5. B7.6 The wave height of the bottom solution increases linearly with the amount of diacetyl, so the amount added must be accurate. B7.7 To prevent nitric acid from boiling or reacting violently The nitrogen oxide gas flow produced during the digestion causes splashing losses. First, digestion is carried out at about 110°C, and then the temperature is raised in the later stage to drive away the residual perchloric acid. B7.8 Adding anhydrous sodium sulfite can improve the reproducibility of this method and make the waveform regular, but all anhydrous sodium sulfite contains trace nickel to varying degrees. When switching to other batches, a maximum addition amount experiment must be performed. B7.9 The silver-mercury electrode must be cleaned immediately after use and immersed in water. B7.10 The digestion device III is preferably made of polytetrafluoroethylene. Quartz products adsorb nickel chloride but not nickel nitrate. B7.11 All instruments used in the experiment must be 1 :3 (hydrochloric acid: nitric acid) mixed acid soak for 3 days, and used utensils soak in 1:1 nitric acid for 1 day. B7.12 microporous filter membrane is not suitable for collecting nickel-containing aqueous aerosol air samples. 455
Additional instructions:
GB16210—1996
This standard is proposed by the Ministry of Health of the People's Republic of China. This standard was drafted by Harbin Medical University and Gansu Provincial Health and Epidemic Prevention Station. The main drafters of this standard are Gang Baoqi and Li Shusen. This standard is interpreted by the Institute of Labor Hygiene and Occupational Diseases, Chinese Academy of Preventive Medicine, which is the technical management unit entrusted by the Ministry of Health. 45612 Microporous filter membrane is not suitable for collecting nickel-containing aqueous aerosol air samples. 455
Additional Notes:
GB16210—1996
This standard was proposed by the Ministry of Health of the People's Republic of China. This standard was drafted by Harbin Medical University and Gansu Provincial Health and Epidemic Prevention Station. The main drafters of this standard were Gang Baoqi and Li Shusen. This standard was interpreted by the Institute of Labor Hygiene and Occupational Diseases, Chinese Academy of Preventive Medicine, the technical unit entrusted by the Ministry of Health. 45612 Microporous filter membrane is not suitable for collecting nickel-containing aqueous aerosol air samples. 455
Additional Notes:
GB16210—1996
This standard was proposed by the Ministry of Health of the People's Republic of China. This standard was drafted by Harbin Medical University and Gansu Provincial Health and Epidemic Prevention Station. The main drafters of this standard were Gang Baoqi and Li Shusen. This standard was interpreted by the Institute of Labor Hygiene and Occupational Diseases, Chinese Academy of Preventive Medicine, the technical unit entrusted by the Ministry of Health. 456
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