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GB 50325-2020   Standard for indoor environmental pollution control of civil building engineering (English Version)
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Standard No.: GB 50325-2020
English Name: Standard for indoor environmental pollution control of civil building engineering
Chinese Name: 民用建筑工程室内环境污染控制标准
Professional Classification: GB    National Standard
Source Content Issued by: MOHURD
Issued on: 2020-01-16
Implemented on: 2020-8-1
Status: valid
Superseding:GB 50325-2010 Code for indoor environmental pollution control of civil building engineering
GB 50325-2010(2013) Code for indoor environmental pollution control of civil building engineering (2013)
Target Language: English
File Format: PDF
Word Count: 18500 words
Translation Price(USD): 555.0
Delivery: via email in 1 business day
Codeofchina.com is in charge of this English translation. In case of any doubt about the English translation, the Chinese original shall be considered authoritative. According to the requirements of Document JIAN BIAO HAN [2015] No.274 issued by the Ministry of Housing and Urban-Rural Development of the People's Republic of China—Notice on printing and distributing the ‘Plan 2016 on the development and revision of engineering construction standards and codes’, the drafting group has revised this standard through extensive investigation and study, careful summarization of practical experience and consultation with relevant international and foreign advanced standards and on the basis of widely soliciting for opinions. The technical contents of this standard mainly include the general provisions, terms and symbols, building materials, survey and designing for building engineering, construction, and acceptance. The technical revisions to this standard are made as follows: 1. Toluene and xylene have been added to indoor air pollutants; 2. The classification of decoration materials has been refined, and the limits and measurement methods of pollutant content (emission) of some materials have been modified; 3. The environmental test chamber method and desiccator method for measurement of formaldehyde emission from wood-based panels have been retained; 4. Pre-assessment requirements for pollution control and specific requirements for material selection have been proposed for interior decoration design; 5. Specific requirements for the minimum ventilation frequency of Category I civil buildings adopting natural ventilation haven been proposed; 6. The comprehensive radon prevention measures of buildings have been improved; 7. More stringent pollution control requirements have been proposed for the decoration of kindergartens, school classrooms, student dormitories, etc.; 8. The method for measurement of radon concentration in indoor air has been articulated; 9. The limit value of pollutant concentration in indoor air has been re-defined; 10. Method for sampling and measuring benzene series and volatile organic compounds (TVOC) using T-C composite adsorption tube has been introduced, and the sampling and measurement requirements of indoor air pollutants have been further improved and refined. The provisions printed in bold type in this standard are compulsory and must be enforced strictly. The Ministry of Housing and Urban-Rural Development of the People's Republic of China is in charge of the administration of this standard and the explanation of the compulsory provisions; Henan Provincial Academy of Building Research is responsible for the interpretation of specific technical contents. In case of any comment or suggestion in the process of implementing this standard, please send it to Henan Provincial Academy of Building Research (Address: No.4 Fengle Road, Zhengzhou City, Henan Province, 450053 China). Standard for indoor environmental pollution control of civil building engineering 1 General provisions 1.0.1 This standard is developed in order to prevent and control indoor environmental pollution caused by major materials and decoration materials in civil building engineering, protect public health, safeguard public interests, and achieve advanced level of technology and economic efficiency. 1.0.2 This standard is applicable to indoor environmental pollution control for new construction, extension and renovation of civil buildings. 1.0.3 Indoor environmental pollutants controlled by this standard include radon, formaldehyde, ammonia, benzene, toluene, xylene and total volatile organic compounds. 1.0.4 Civil buildings shall be classified as follows: 1 Category I civil buildings shall include residential buildings, residential apartments, hospital wards, housing facilities for elderly care, kindergartens, school classrooms, student dormitories, etc.; 2 Category II civil buildings shall include office buildings, shops, hotels, cultural and entertainment venues, bookstores, libraries, exhibition halls, gymnasiums, public transportation waiting rooms, restaurants, etc. 1.0.5 The major materials and decoration materials selected for civil building engineering shall comply with the relevant provisions of this standard. 1.0.6 The indoor environmental pollution control of civil buildings shall comply with current relevant national standards, in addition to this standard. 2 Terms and symbols 2.1 Terms 2.1.1 civil building engineering generic term for civil building engineering and decoration engineering in new construction, extension and renovation 2.1.2 environmental test chamber setup that simulates indoor environment to measure the emissions of chemical pollutants from decoration materials 2.1.3 radon exhalation rate from the surface radioactivity of radon exhaled from the surface of soil or material per unit area and time 2.1.4 internal exposure index (IRa) quotient obtained by dividing the specific activity of the natural radionuclide radium-226 in the major materials and decoration materials of the building by the specific activity limit value of 200 2.1.5 external exposure index (Iγ) sum of the quotients obtained by dividing the specific activity of the natural radionuclide radium-226, thorium-232 and potassium-40 in the major materials and decoration materials of the building by the specific activity limit value of 370, 260 and 4200 respectively 2.1.6 radon concentration radioactivity of radon in air per unit volume 2.1.7 wood-based panels panels assembled with blanks by means of adhesive, or formed products, which are composed of material units, made from wood or non-wood plant fibers as the main raw materials, with or without adhesive and other additive applied, mainly including plywood, fiberboard, particleboard and its surface decorative panel 2.1.8 wood-plastic composite products product made of wood fiber material and thermoplastic polymer in a certain proportion, mainly including wood-plastic flooring, wood-plastic decorative panels, wood-plastic doors, etc. 2.1.9 water-based treatment agents liquid with water as diluent that can be absorbed into the major materials and decoration materials so as to improve its flame-retardant, waterproof, and anti-corrosion properties 2.1.10 bulk construction adhesive adhesive, the solvent content or water content of which accounts for less than 5% of the total mass of the adhesive 2.1.11 total volatile organic compounds total amount of volatile organic compounds in the air measured under the conditions specified hereof, henceforth “TVOC” 2.1.12 volatile organic compound total amount of volatile organic compounds in the material measured under the conditions specified hereof, henceforth “VOC” 2.1.13 decoration material loading factor ratio of the total exposed area of decoration materials used to the net space volume of the room, in interior decoration 2.2 Symbols fi——mass percentage of the i-th material in the total material consumption; IRa——internal exposure index; Iγ——external exposure index; IRai——internal exposure index of the i-th material; Iγi——external exposure index of the i-th material. 3 Building materials 3.1 Inorganic non-metallic major materials and decoration materials 3.1.1 For inorganic non-metallic major building materials such as sand, stone, brick, solid block, cement, concrete, and prefabricated concrete components used in civil building engineering, the radioactivity limit shall comply with the current national standard GB 6566 Limits of radionuclides in building materials. 3.1.2 For inorganic non-metallic decoration materials such as stone, building sanitary ceramics, gypsum products and inorganic powder bonding materials used in civil building engineering, classification of the radioactivity limits shall comply with the current national standard GB 6566 Limits of radionuclides in building materials. 3.1.3 When aerated concrete products, and major materials, e.g., hollow bricks and blocks, with a void rate larger than 25% are used in civil building engineering, the radioactivity limit shall comply with the provisions given in Table 3.1.3. Table 3.1.3 Radioactivity limit of aerated concrete products and major materials with a void rate larger than 25% Measurement item Limit Radon exhalation rate from the surface [Bq/(m2·s)] ≤0.015 Internal exposure index (IRa) ≤1.0 External exposure index (Ir) ≤1.3 3.1.4 The measurement method for radionuclide in major materials and decoration materials shall comply with relevant provisions of the current national standard GB 6566 Limits of radionuclides in building materials, and that for radon exhalation rate from the surface shall comply with Annex A of this standard. 3.2 Wood-based panels and their products 3.2.1 The emission of free formaldehyde shall be determined for wood-based panels and their products used indoors in civil building engineering. 3.2.2 The formaldehyde emission of wood-based panels and their products may be determined by environmental test chamber method or desiccator method. In the event of a dispute, the environmental test chamber method shall prevail. 3.2.3 The free formaldehyde emission of wood-based panels and their products determined by the environmental test chamber method shall not be larger than 0.124mg/m3, and the measurement method shall be implemented in accordance with Annex B of this standard. 3.2.4 The free formaldehyde emission of wood-based panels and their products determined by desiccator method shall not be larger than 1.5mg/L, and the measurement method shall comply with the current national standard GB/T 17657 Test methods of evaluating the properties of wood-based panels and surface decorated wood-based panels. 3.3 Coating 3.3.1 The free formaldehyde limit of water-based decorative panel coatings, water-based wall coatings, and water-based wall putty for indoor use in civil building engineering shall comply with the current national standard GB 18582 Limit of harmful substances of architectural wall coatings. 3.3.2 For other water-based coatings and water-based putty for indoor use in civil building engineering, the content of free formaldehyde shall be determined, its limit shall comply with the provisions given in Table 3.3.2, and its determination method shall comply with the current national standard GB/T 23993 Determination of formaldehyde content of waterborne coatings—Spectrophotometric method with acetylacetone. Table 3.3.2 Limits of free formaldehyde in other water-based coating and water-based putty for indoor use Measurement item Limit Other water-based coating Other water-based putty Free formaldehyde (mg/kg) ≤100 3.3.3 For indoor use in civil building engineering, the limits of VOC, benzene, and toluene + xylene + ethylbenzene of solvent-based decorative panel coatings shall comply with the current national standard GB 18582 Limit of harmful substances of architectural wall coatings, that of solvent-based woodware coating and putty shall comply with the current national standard GB 18581 Limit of harmful substances of woodware coatings. The limits of VOC, benzene, and that of solvent-based floor coating shall comply with the current national standard GB 38468 Limit of harmful substances of interior floor coatings. 3.3.4 Phenolic anti-corrosion coatings, waterproof coatings, fire resistive coatings and other solvent-based coatings for indoor use in civil building engineering shall be mixed according to the respective specified maximum dilution ratio, and then the contents of VOC, benzene, and toluene + xylene + ethylbenzene shall be determined, and their limits shall comply with the provisions given in Table 3.3.4; the measurement method of VOC content shall comply with the current national standard GB/T 23985 Paints and varnishes—Determination of volatile organic compound (VOC) content—Difference method, and the measurement methods of benzene and toluene + xylene + ethylbenzene contents shall comply with the current national standard GB/T 23990 Determination of the contents of benzene toluene ethylbenzene and xylene in coatings by gas chromatography.
Foreword ii 1 General provisions 2 Terms and symbols 3 Building materials 4 Survey and designing for building engineering 5 Construction 6 Inspection and acceptance Annex A Measurement of radon exhalation rate Annex B Measurement of content of formaldehyde and VOC emission in decoration materials using environmental test chamber Annex C Measurements of radon concentration in soil and radon exhalation rate Annex D Measurement of indoor benzene, toluene and xylene Annex E Measurement of indoor TVOC Explanation of wording in this standard List of quoted standards
Referred in GB 50325-2020:
*GB 50108-2008 Technical Code for Waterproofing of Underground Works
*GB 50352-2019 Unified standard for design of civil building
*GB 50736-2012 Design Code for Heating Ventilation and Air Conditioning of Civil Buildings
*GB 6566-2010 Limits of radionuclides in building materials
*GB/T 16143-1995 Charcoal canister method for measuring 222Rn exhalation rate from building surface
*GB/T 17657-2022 Test methods of evaluating the properties of wood-based panels and surface decorated wood-based panels
*GB/T 18204.2-2014 Examination methods for public places—Part 2:Chemical pollutants
*GB 18581-2020 Limit of harmful substances of woodware coatings
*GB 18582-2020 Limit of harmful substances of architectural wall coatings
*GB 18585-2001 Indoor decorating and refurbishing materials-Limit of harmful substances of wallpapers
*GB 18586-2001 Indoor decorating and refurbishing materials-Limit of harmful substances of polyvinyl chloride floor coverings
*GB 18588-2001 Limit of ammonia emitted from the concrete admixtures
*GB/T 23985-2009 Paints and varnishes - Determination of volatile organic compound (VOC) content - Difference method
*GB/T 23993-2009 Determination of formaldehyde content of waterborne coatings—Spectrophtometric method with acetylacetone
*GB/T 23990-2009 Determination of the contents of benzene toluene ethylbenzene and xylene in coatings by gas chromatography
*GB 30982-2014 Limit of hazardous substances in construction adhesive
*GB 31040-2014 Limit of residual formaldehyde from the concrete admixtures
*GB/T 33372-2016 Limit of volatile organic compound content in adhesives
*GB 38468-2019 Limit of harmful substances of interior floor coatings
*JG/T 415-2013 Limit and Test Method of Harmful Substances in Fire-retardant Coating
GB 50325-2020 is referred in:
*DBJ 15-93-2013 Technical code for indoor environmental pollution control of civil building engineering
*JGJ/T 331-2014 Technical Specification for Slip Resistance of Buildings Floor
*DB 44/816-2010 Emission standard of volatile organic compounds for surface coating of automobile manufacturing industry
*GB 28489-2022 Limits of hazardous substances for musical instruments
*GB 50210-2018 Standard for construction quality acceptance of building decoration
*JGJ/T 67-2019 Standard for design of office building
*GB/T 9981-2025 Hygienic specification for rural residential buildings
Code of China
Standard
GB 50325-2020  Standard for indoor environmental pollution control of civil building engineering (English Version)
Standard No.GB 50325-2020
Statusvalid
LanguageEnglish
File FormatPDF
Word Count18500 words
Price(USD)555.0
Implemented on2020-8-1
Deliveryvia email in 1 business day
Detail of GB 50325-2020
Standard No.
GB 50325-2020
English Name
Standard for indoor environmental pollution control of civil building engineering
Chinese Name
民用建筑工程室内环境污染控制标准
Chinese Classification
Professional Classification
GB
ICS Classification
Issued by
MOHURD
Issued on
2020-01-16
Implemented on
2020-8-1
Status
valid
Superseded by
Superseded on
Abolished on
Superseding
GB 50325-2010 Code for indoor environmental pollution control of civil building engineering
GB 50325-2010(2013) Code for indoor environmental pollution control of civil building engineering (2013)
Language
English
File Format
PDF
Word Count
18500 words
Price(USD)
555.0
Keywords
GB 50325-2020, GB/T 50325-2020, GBT 50325-2020, GB50325-2020, GB 50325, GB50325, GB/T50325-2020, GB/T 50325, GB/T50325, GBT50325-2020, GBT 50325, GBT50325
Introduction of GB 50325-2020
Codeofchina.com is in charge of this English translation. In case of any doubt about the English translation, the Chinese original shall be considered authoritative. According to the requirements of Document JIAN BIAO HAN [2015] No.274 issued by the Ministry of Housing and Urban-Rural Development of the People's Republic of China—Notice on printing and distributing the ‘Plan 2016 on the development and revision of engineering construction standards and codes’, the drafting group has revised this standard through extensive investigation and study, careful summarization of practical experience and consultation with relevant international and foreign advanced standards and on the basis of widely soliciting for opinions. The technical contents of this standard mainly include the general provisions, terms and symbols, building materials, survey and designing for building engineering, construction, and acceptance. The technical revisions to this standard are made as follows: 1. Toluene and xylene have been added to indoor air pollutants; 2. The classification of decoration materials has been refined, and the limits and measurement methods of pollutant content (emission) of some materials have been modified; 3. The environmental test chamber method and desiccator method for measurement of formaldehyde emission from wood-based panels have been retained; 4. Pre-assessment requirements for pollution control and specific requirements for material selection have been proposed for interior decoration design; 5. Specific requirements for the minimum ventilation frequency of Category I civil buildings adopting natural ventilation haven been proposed; 6. The comprehensive radon prevention measures of buildings have been improved; 7. More stringent pollution control requirements have been proposed for the decoration of kindergartens, school classrooms, student dormitories, etc.; 8. The method for measurement of radon concentration in indoor air has been articulated; 9. The limit value of pollutant concentration in indoor air has been re-defined; 10. Method for sampling and measuring benzene series and volatile organic compounds (TVOC) using T-C composite adsorption tube has been introduced, and the sampling and measurement requirements of indoor air pollutants have been further improved and refined. The provisions printed in bold type in this standard are compulsory and must be enforced strictly. The Ministry of Housing and Urban-Rural Development of the People's Republic of China is in charge of the administration of this standard and the explanation of the compulsory provisions; Henan Provincial Academy of Building Research is responsible for the interpretation of specific technical contents. In case of any comment or suggestion in the process of implementing this standard, please send it to Henan Provincial Academy of Building Research (Address: No.4 Fengle Road, Zhengzhou City, Henan Province, 450053 China). Standard for indoor environmental pollution control of civil building engineering 1 General provisions 1.0.1 This standard is developed in order to prevent and control indoor environmental pollution caused by major materials and decoration materials in civil building engineering, protect public health, safeguard public interests, and achieve advanced level of technology and economic efficiency. 1.0.2 This standard is applicable to indoor environmental pollution control for new construction, extension and renovation of civil buildings. 1.0.3 Indoor environmental pollutants controlled by this standard include radon, formaldehyde, ammonia, benzene, toluene, xylene and total volatile organic compounds. 1.0.4 Civil buildings shall be classified as follows: 1 Category I civil buildings shall include residential buildings, residential apartments, hospital wards, housing facilities for elderly care, kindergartens, school classrooms, student dormitories, etc.; 2 Category II civil buildings shall include office buildings, shops, hotels, cultural and entertainment venues, bookstores, libraries, exhibition halls, gymnasiums, public transportation waiting rooms, restaurants, etc. 1.0.5 The major materials and decoration materials selected for civil building engineering shall comply with the relevant provisions of this standard. 1.0.6 The indoor environmental pollution control of civil buildings shall comply with current relevant national standards, in addition to this standard. 2 Terms and symbols 2.1 Terms 2.1.1 civil building engineering generic term for civil building engineering and decoration engineering in new construction, extension and renovation 2.1.2 environmental test chamber setup that simulates indoor environment to measure the emissions of chemical pollutants from decoration materials 2.1.3 radon exhalation rate from the surface radioactivity of radon exhaled from the surface of soil or material per unit area and time 2.1.4 internal exposure index (IRa) quotient obtained by dividing the specific activity of the natural radionuclide radium-226 in the major materials and decoration materials of the building by the specific activity limit value of 200 2.1.5 external exposure index (Iγ) sum of the quotients obtained by dividing the specific activity of the natural radionuclide radium-226, thorium-232 and potassium-40 in the major materials and decoration materials of the building by the specific activity limit value of 370, 260 and 4200 respectively 2.1.6 radon concentration radioactivity of radon in air per unit volume 2.1.7 wood-based panels panels assembled with blanks by means of adhesive, or formed products, which are composed of material units, made from wood or non-wood plant fibers as the main raw materials, with or without adhesive and other additive applied, mainly including plywood, fiberboard, particleboard and its surface decorative panel 2.1.8 wood-plastic composite products product made of wood fiber material and thermoplastic polymer in a certain proportion, mainly including wood-plastic flooring, wood-plastic decorative panels, wood-plastic doors, etc. 2.1.9 water-based treatment agents liquid with water as diluent that can be absorbed into the major materials and decoration materials so as to improve its flame-retardant, waterproof, and anti-corrosion properties 2.1.10 bulk construction adhesive adhesive, the solvent content or water content of which accounts for less than 5% of the total mass of the adhesive 2.1.11 total volatile organic compounds total amount of volatile organic compounds in the air measured under the conditions specified hereof, henceforth “TVOC” 2.1.12 volatile organic compound total amount of volatile organic compounds in the material measured under the conditions specified hereof, henceforth “VOC” 2.1.13 decoration material loading factor ratio of the total exposed area of decoration materials used to the net space volume of the room, in interior decoration 2.2 Symbols fi——mass percentage of the i-th material in the total material consumption; IRa——internal exposure index; Iγ——external exposure index; IRai——internal exposure index of the i-th material; Iγi——external exposure index of the i-th material. 3 Building materials 3.1 Inorganic non-metallic major materials and decoration materials 3.1.1 For inorganic non-metallic major building materials such as sand, stone, brick, solid block, cement, concrete, and prefabricated concrete components used in civil building engineering, the radioactivity limit shall comply with the current national standard GB 6566 Limits of radionuclides in building materials. 3.1.2 For inorganic non-metallic decoration materials such as stone, building sanitary ceramics, gypsum products and inorganic powder bonding materials used in civil building engineering, classification of the radioactivity limits shall comply with the current national standard GB 6566 Limits of radionuclides in building materials. 3.1.3 When aerated concrete products, and major materials, e.g., hollow bricks and blocks, with a void rate larger than 25% are used in civil building engineering, the radioactivity limit shall comply with the provisions given in Table 3.1.3. Table 3.1.3 Radioactivity limit of aerated concrete products and major materials with a void rate larger than 25% Measurement item Limit Radon exhalation rate from the surface [Bq/(m2·s)] ≤0.015 Internal exposure index (IRa) ≤1.0 External exposure index (Ir) ≤1.3 3.1.4 The measurement method for radionuclide in major materials and decoration materials shall comply with relevant provisions of the current national standard GB 6566 Limits of radionuclides in building materials, and that for radon exhalation rate from the surface shall comply with Annex A of this standard. 3.2 Wood-based panels and their products 3.2.1 The emission of free formaldehyde shall be determined for wood-based panels and their products used indoors in civil building engineering. 3.2.2 The formaldehyde emission of wood-based panels and their products may be determined by environmental test chamber method or desiccator method. In the event of a dispute, the environmental test chamber method shall prevail. 3.2.3 The free formaldehyde emission of wood-based panels and their products determined by the environmental test chamber method shall not be larger than 0.124mg/m3, and the measurement method shall be implemented in accordance with Annex B of this standard. 3.2.4 The free formaldehyde emission of wood-based panels and their products determined by desiccator method shall not be larger than 1.5mg/L, and the measurement method shall comply with the current national standard GB/T 17657 Test methods of evaluating the properties of wood-based panels and surface decorated wood-based panels. 3.3 Coating 3.3.1 The free formaldehyde limit of water-based decorative panel coatings, water-based wall coatings, and water-based wall putty for indoor use in civil building engineering shall comply with the current national standard GB 18582 Limit of harmful substances of architectural wall coatings. 3.3.2 For other water-based coatings and water-based putty for indoor use in civil building engineering, the content of free formaldehyde shall be determined, its limit shall comply with the provisions given in Table 3.3.2, and its determination method shall comply with the current national standard GB/T 23993 Determination of formaldehyde content of waterborne coatings—Spectrophotometric method with acetylacetone. Table 3.3.2 Limits of free formaldehyde in other water-based coating and water-based putty for indoor use Measurement item Limit Other water-based coating Other water-based putty Free formaldehyde (mg/kg) ≤100 3.3.3 For indoor use in civil building engineering, the limits of VOC, benzene, and toluene + xylene + ethylbenzene of solvent-based decorative panel coatings shall comply with the current national standard GB 18582 Limit of harmful substances of architectural wall coatings, that of solvent-based woodware coating and putty shall comply with the current national standard GB 18581 Limit of harmful substances of woodware coatings. The limits of VOC, benzene, and that of solvent-based floor coating shall comply with the current national standard GB 38468 Limit of harmful substances of interior floor coatings. 3.3.4 Phenolic anti-corrosion coatings, waterproof coatings, fire resistive coatings and other solvent-based coatings for indoor use in civil building engineering shall be mixed according to the respective specified maximum dilution ratio, and then the contents of VOC, benzene, and toluene + xylene + ethylbenzene shall be determined, and their limits shall comply with the provisions given in Table 3.3.4; the measurement method of VOC content shall comply with the current national standard GB/T 23985 Paints and varnishes—Determination of volatile organic compound (VOC) content—Difference method, and the measurement methods of benzene and toluene + xylene + ethylbenzene contents shall comply with the current national standard GB/T 23990 Determination of the contents of benzene toluene ethylbenzene and xylene in coatings by gas chromatography.
Contents of GB 50325-2020
Foreword ii 1 General provisions 2 Terms and symbols 3 Building materials 4 Survey and designing for building engineering 5 Construction 6 Inspection and acceptance Annex A Measurement of radon exhalation rate Annex B Measurement of content of formaldehyde and VOC emission in decoration materials using environmental test chamber Annex C Measurements of radon concentration in soil and radon exhalation rate Annex D Measurement of indoor benzene, toluene and xylene Annex E Measurement of indoor TVOC Explanation of wording in this standard List of quoted standards
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Keywords:
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