China’s chemical purity classification and safety measures guide

1.Definition of purity grade: The purity grade of Chinese chemicals is divided according to the purity of its internal target substances and related indicators. Different purity levels represent different purity requirements and application ranges.
2.Common purity grades: According to national standards, common purity grades of Chinese chemicals include:
(1) Industrial grade chemicals:
What it means: Industrial grade chemicals are primarily used in general industrial processing and manufacturing. Its purity requirements are relatively low and it can contain certain amounts of impurities and other ingredients.
Purity requirements: Industrial-grade chemicals generally do not have strict purity requirements, but must meet relevant technical specifications and safety standards.
Application fields: Industrial grade chemicals are widely used in various industrial fields, such as chemical production, building materials, plastic processing, metal processing, etc.
(2) Pesticide grade chemicals:
Meaning: Pesticide-grade chemicals are mainly used in the agricultural sector for crop protection and pesticide manufacturing. Its purity requirements are high to ensure its effectiveness and safety in agricultural applications.
Purity requirements: Pesticide-grade chemicals have higher purity requirements than industrial-grade chemicals. Most impurities usually need to be removed and must meet national pesticide registration requirements.
Application fields: Pesticide-grade chemicals are mainly used in plant protection and pest control in agricultural production.
(3) Pharmaceutical grade chemicals:
Meaning: Pharmaceutical grade chemicals are mainly used in the pharmaceutical and medical fields. Its purity requirements are very high to ensure the quality, safety and efficacy of the drug.
Purity requirements: Pharmaceutical grade chemicals must have extremely high purity and usually require strict process control, fine separation and purification to meet the requirements of the National Pharmacopoeia or related standards.
Application fields: Pharmaceutical grade chemicals are mainly used in the synthesis of raw materials, drug research and development, and preparation of preparations in the pharmaceutical process.
(4) Experimental grade chemicals:
What it means: Experimental grade chemicals are primarily used in scientific research and laboratory applications. Its purity requirements are high to provide reliable experimental results.
Purity requirements: Laboratory-grade chemicals need to have high purity and certain stability to meet the accuracy and repeatability of experimental results.
Application fields: Experimental grade chemicals are widely used in scientific research, teaching and laboratory exploration fields, such as chemical analysis, organic synthesis, biological research, etc.
(5) Analytical grade chemicals:
Meaning: Analytical grade chemicals are primarily used for chemical analysis and quality control. Its purity requirements are very high to ensure accurate analytical results.
Purity requirements: Analytical grade chemicals need to have extremely high purity and stability, and usually need to undergo rigorous process flow and validation testing to meet the requirements of analytical methods.
Application areas: Analytical grade chemicals are mainly used in standard solution preparation, instrument calibration, quality control and chemical analysis.
3.Purity testing methods: In order to determine the purity of chemicals, various testing methods are usually used for verification and detection. Here are some common purity testing methods:
(1) Specific gravity determination: By measuring the density or specific gravity of a substance, its purity can be inferred. This method works for both liquid and solid chemicals.
(2) Chromatography: Chromatography is a method of separating and analyzing chemical components. Common chromatography methods include gas chromatography (GC) and liquid chromatography (LC), which can be used for quantitative analysis and purity testing.
(3) Spectroscopy: Spectroscopic techniques (such as ultraviolet-visible spectroscopy, infrared spectroscopy, mass spectrometry, etc.) can determine the composition and purity of a substance by measuring its interaction with light.
(4) Thermal analysis method: Thermal analysis techniques, such as differential scanning calorimeter (DSC) and thermogravimetric analysis (TGA), can infer the purity of a material by detecting its property changes under temperature changes.
(5) Nuclear Magnetic Resonance (NMR): Nuclear Magnetic Resonance is a very powerful analytical method that can be used to determine the structure and purity of chemicals.
4.Purity applications: Chemicals with different purity levels have different applications in different fields. Here are some common application examples:
(1) Analytical laboratories: High-purity chemicals are often used in analytical laboratories for the preparation of standard solutions, quality control, instrument calibration, etc.
(2) Pharmaceutical industry: In the pharmaceutical process, high-purity chemicals are usually used for drug synthesis, API extraction and preparation preparation.
(3) Electronics industry: Special pure chemicals are widely used in semiconductor manufacturing, optical materials, display screen manufacturing and other fields.
(4) Cosmetics and personal care products: Pure chemicals are often used in the manufacture of cosmetics and personal care products to ensure their quality and safety.
(5) Agriculture and pesticides: The agricultural field uses high-purity chemicals for crop protection and fertilizer production to increase the yield and quality of agricultural products.
5.Classification of chemicals: Chemicals can be classified according to their properties, uses and hazard levels. Here are some common chemical classifications:
(1) Organic chemicals: compounds mainly composed of carbon and hydrogen, including hydrocarbons, alcohols, ketones, etc.
(2) Inorganic chemicals: compounds that contain no carbon or only a small amount of carbon, such as oxides, salts, etc.
(3) Toxic chemicals: chemicals that are harmful to the human body or the environment, including carcinogens, nerve agents, heavy metals, etc.
(4) Corrosive chemicals: chemicals that can damage tissues, cause irritation or corrosion, such as strong acids, strong bases, etc.
(5) Flammable chemicals: Flammable or combustible chemicals, such as solvents, liquid fuels, etc.
6.Chemical safety measures: When handling and storing chemicals, there are a number of safety measures that need to be followed to minimize potential hazards. Here are some common chemical safety measures:
(1) Read labels and safety data sheets (SDS): Learn in detail about the chemical’s composition, properties, safety precautions and first aid measures.
(2) Appropriate storage conditions: Choose the correct storage method based on the characteristics of the chemical, including temperature, humidity and ventilation conditions.
(3) Use personal protective equipment: Wear appropriate personal protective equipment such as gloves, goggles, protective clothing, etc. based on the characteristics of the chemical.
(4) Follow operating procedures: Use chemicals correctly according to safe operating procedures and avoid reactions with other substances.
(5) Dispose of waste: Dispose of chemical waste correctly, follow local regulations and adopt appropriate disposal methods.
(6) Response to emergencies: If a chemical leak, accident or emergency situation occurs, you need to take appropriate measures immediately to protect yourself and others. This may include leaving the danger zone quickly, calling professionals and providing first aid measures.
7.Compliance and regulations: Regulations and compliance requirements for the use and handling of chemicals vary from country to country. When using chemicals, make sure to comply with local regulations and requirements and consult professionals for accurate guidance.
This chemical guide provides some basic information, but please note that before engaging in any chemical-related activities, please understand in detail the properties, uses, safety precautions and regulatory requirements of specific chemicals. Make sure you have the necessary knowledge and skills to manage and handle chemicals safely. If you need more specific information or have specific questions, please consult professionals or local relevant agencies. Safety is always the first consideration when handling chemicals. I wish you safety and success in your work and life in the field of chemicals!

Reference for purity grades of commonly used analytical chemicals in China

中文名称	Name	Grade	Application
基准试剂	Primary reagent	PT	可直接配制标准溶液，专门作为基准物用。 The standard solution can be directly prepared and used as a reference material.
优级纯	Guaranteed reagent	GR	主成份含量很高、纯度很高，适用于精确分析和研究工作，有的可作为基准物质。 The main component content is very high and the purity is very high, which is suitable for precise analysis and research work, and some can be used as reference substances.
分析纯	Analytial reagent	AR	主成份含量很高、纯度较高，干扰杂质很低，适用于工业分析及化学实验。 The main component content is very high, the purity is high, and the interfering impurities are very low. It is suitable for industrial analysis and chemical experiments.
化学纯	Chemical pure	CP	主成份含量高、纯度较高，存在干扰杂质，适用于化学实验和合成制备。 The main component content is high, the purity is high, and there are interfering impurities, which makes it suitable for chemical experiments and synthetic preparations.
实验纯	Laboratory reagent	LR	主成份含量高、纯度较差，杂质含量不做选择，只适用于一般化学实验和合成制备。 The main component content is high and the purity is poor. The impurity content is not selected. It is only suitable for general chemical experiments and synthetic preparations.
工业级	Industrial grade		主成份含量高、纯度较差，杂质含量不做选择，只适用于一般对纯度精度不严格的工业生产用途。 The main component content is high, the purity is poor, and the impurity content is not selected. It is only suitable for industrial production where purity accuracy is not strict.
生化试剂	Biological reagent	BR	用于配制生物化学检验试液，和生化合成。质量指标注重生物活性杂质。可替代指示剂和有机合成。 Used for preparing biochemical test solutions and biochemical synthesis. The quality index focuses on biologically active impurities. It can replace indicators and organic synthesis.
生物染色剂	Biological stain	BS	适用于配制生物标本染色液。质量指标注重生物活性杂质。可替代指示剂和有机合成。 Suitable for preparing biological specimen staining solution. Quality index focuses on biologically active impurities. Can replace indicators and organic synthesis.
显色剂	Indicator	Ind	一般在配制指示溶液过程中应用用，主要指标是变色范围和变色敏感程度，可替代CP级试剂,也适用于有机合成使用。 It is generally used in the preparation of indicator solutions. The main indicators are the color change range and color change sensitivity. It can replace CP-grade reagents and is also suitable for use in organic synthesis.
气相色谱	gas chromatography	GC	气相色谱分析专用试剂，该试剂指标注重干扰气相色谱峰的杂质，主成分含量较高。 Special reagent for gas chromatography analysis. The reagent index focuses on impurities that interfere with gas chromatography peaks, and the main component content is relatively high.
液相色谱	High performance liquid chromatography	Hplc	液相色谱分析标准品。该标品主要指标注重干扰液相色谱峰的杂质，主成分含量很高。 Liquid chromatography analysis standard. The main indicator of this standard product focuses on impurities that interfere with the liquid chromatography peak, and the main component content is very high.
农残级	PR	/	适应于农残分析、光谱分析、 HPLC 、 GC 、有机合成及组合化学等多方面的应用。 It is suitable for applications in pesticide residue analysis, spectral analysis, HPLC, GC, organic synthesis and combinatorial chemistry.
光谱纯	Spectrum pure	SP	由于有机物在光谱上显示不出，所以有时主成分达不到99.9%以上，使用时必须注意，特别是作基准物时，必须进行标定。 Since organic matter cannot be shown in the spectrum, sometimes the main component cannot reach above 99.9%. You must be careful when using it, especially when using it as a reference material, calibration must be carried out.
质谱级	LC-MS	/	适用于液相色谱-质谱联用仪（LC-MS）与液相二级质谱仪（LC-MS-MS）。 Suitable for liquid chromatography-mass spectrometry (LC-MS) and liquid chromatography-mass spectrometry (LC-MS-MS).
超纯	Ultra Pure	UP	超纯，与GR级相近。 Ultra-pure, similar to GR grade.
高纯	High Purity	HP	高纯，与AR级相近。 High purity, similar to AR grade.
生物技术级	Biotech	/	生物技术级，与BR级相近。 Biotech grade, similar to BR grade.
试剂级	Reagent	/	试剂级，与CP级相近。 Reagent grade, similar to CP grade.
美国化学学会标准	ACS	/	美国化学学会标准，与AR级相近。 American Chemical Society standard, similar to AR grade.
药用级	USP	/	美国药典标准。 USP Standards.
电泳试剂	Electrophoresis reagents	ER	质量指标注重电性杂质含量控制。 The quality indicators focus on the control of electrical impurity content.
电子纯	Metal-Oxide-Semiconductor	MOS	即UP-S级或MOS试剂(读作：摩斯试剂)。一般用于半导体，电子管等方面，其杂质最高含量为0.01-10ppm，有的可降低到ppb数量级，金属杂质含量小于1ppb，尘埃等级达到0-2ppb，适合0.35—0.8微米集成电路加工工艺。 That is, UP-S grade or MOS reagent (pronounced as: Moss reagent). It is generally used in semiconductors, electron tubes, etc. Its maximum impurity content is 0.01-10ppm, and some can be reduced to the ppb level. The metal impurity content is less than 1ppb, and the dust level reaches 0-2ppb, which is suitable for 0.35-0.8 micron integrated circuit processing technology.
当量试剂	3N、4N、5N	/	主成分含量分别为会在99.9%、99.99%、99.999%以上。 The contents of main components will be above 99.9%, 99.99% and 99.999% respectively.
等离子体质谱纯级	ICP-Mass Pure Grade	/	绝大多数杂质元素含量低于0.1ppb，适合等离子体质谱仪(ICP Mass)日常分析工作。 The content of most impurity elements is less than 0.1ppb, which is suitable for daily analysis of plasma mass spectrometry (ICP Mass).
等离子体发射光谱纯级试剂	ICP Pure Grade	/	绝大多数杂质元素含量低于1ppb ，适合等离子体发射光谱仪(ICP)日常分析工作。 The content of most impurity elements is less than 1ppb, which is suitable for daily analysis by plasma emission spectrometer (ICP).
原子吸收光谱纯级	AA Pure Grade	/	绝大多数杂质元素含量低于10 ppb ，适合原子吸收光谱仪(AA)日常分析工作。 The content of most impurity elements is less than 10 ppb, which is suitable for daily analysis by atomic absorption spectrometer (AA).

Chinese reagent standards

[National Standards]:

The national standard is proposed by the Ministry of Chemical Industry, approved and issued by the National Bureau of Standards. Its code is “GB”, which is taken from the first letter of the Chinese pinyin of the two words “Guo Biao”. Its numbering adopts a sequence number plus a year number, separated by a horizontal line in the middle, and all in Arabic numerals, such as GB2299-80 High Purity Boric Acid, which means National Standard No. 2299, promulgated in 1980.
The “National Standard of the People’s Republic of China • Chemical Reagents” was formulated and published in 1965, and compiled into the “National Standard • Chemical Reagents Compilation” in 1971. The net additional sub-volumes were published in 1978. In 1990, it was published as the “Chemical Industry Standard Compilation • Chemical Reagents” (Volume 13). It divides the purity of chemical reagents into 5 levels, namely, high purity, benchmark, premium purity, analytical purity and chemical purity, among which premium purity is equivalent to the guaranteed reagent (BR) of Merck standard.
The “International Standard of the People’s Republic of China • Chemical Reagents” is the most authoritative reagent standard in my country. In addition to the reagent name, shape, molecular formula, and molecular weight, it also includes four items: technical conditions (minimum reagent content and maximum impurity content, etc.), inspection rules (reagent sampling and acceptance rules), test methods, packaging, and marking.

[Ministry-issued standards]:

Ministry-issued standards are formulated, approved and published by the Ministry of Chemical Industry, and submitted to the National Bureau of Standards for filing. Their code name is “HG”, which is taken from the first letter of the Chinese pinyin of the word “chemical industry”. The numbering format is the same as that of national standards. Same; in addition to ministerial standards, there are also ministerial interim standards, which are interim standards issued by the Ministry of Chemical Industry. The code name is “HGB”, which is taken from the first letter of the three Chinese pinyin of “Ministry of Chemical Industry”. The numbering format is the same as the national standard. same.

[Enterprise Standards]:

The ministerial standards are formulated, approved and issued by the Ministry of Chemical Industry and submitted to the National Bureau of Standards for filing. Their code is “HG”, which is taken from the first letters of the Chinese pinyin of the word “chemical industry”. The numbering format is the same as that of national standards. In addition to the ministerial standards, there are also ministerial interim standards, which are interim standards issued by the Ministry of Chemical Industry. Their code is “HGB”, which is taken from the first letters of the three Chinese pinyin characters of “Ministry of Chemical Industry”. The numbering format is the same as that of national standards.

International reagent standards

[Merck Standard]:

The predecessor of Merck standards is “Purity Testing of Chemical Reagents” compiled by Dr. Krauch, a chemist of Imec Company, published in 1888. This book is accompanied by a list of “Imoc Company and Guaranteed Reagents”. Listed are exactly 130 analytical reagents produced by the company at that time. In 1939, a fifth revised edition was published. According to this tradition, in 1971, Imec published “Merck Standards” (German). This book not only describes the maximum limits of impurities in each Merck Guaranteed Reagent (GR), but also describes in detail the most effective measurement methods. Therefore, it is very popular among all reagent users and is called the “Inspection Encyclopedia”. In the “Merck Standards” published in 1971, there are more than 570 guaranteed reagents (GR). Imec is the first company in the world to formulate and publish reagent standards, and it is also the first company to use percentages to express the minimum content of reagents and the maximum allowable content of impurities. It can be said that the basic style of reagent standards in the world was first established by Imec.

[Rosin Standard]:

The full name is “Reagent Chemical and Standards With methods of testing and assaying”. The author, Joseph Rosin, is a member of the American Chemical Society, former chief chemist of the United States Pharmacopeia Revision Committee and chemical director of Imerk. Since its publication in 1937, the standard has been revised several times in 1946, 1955 and 1967, and the reagent varieties have been continuously supplemented. The fifth edition of the “Rosin Standard” published in 1967 included about 570 analytical reagents. The “Rosin Standard” is currently the most famous academic standard in the world.

[ACS Standards]:

The full name is “Reagent Chemical-American Chemical Society Specifications”, compiled by the Analytical Committee of the American Chemical Society, and is currently the most authoritative reagent standard in the United States. An early text similar to the “ACS Specifications” appeared in 1917 and was used for four chemical reagents (ammonium hydroxide, hydrochloric acid, nitric acid, and sulfuric acid) in the “Industrial and Engineering Chemistry” magazine published in 1921. The current format of the “ACS Specifications” began in 1924-1925. The “ACS Specifications” was published in the form of a volume in 1941. The 1950 edition of the “ACS Specifications” finally collected the revised version and new reagent varieties into one book. Then came the 1955 and 1960 editions. The 4th edition (1968) and the 5th edition (1974), the 6th edition (1981), and the 7th edition (1986).