Standard No.:	GBZ 2.1-2019/XG2-2024
English Name:	Occupational exposure limits for hazardous agents in the workplace― Part 1: Chemical hazardous agents，including Amendment 2
Chinese Name:	工作场所有害因素职业接触限值 第1部分:化学有害因素，含第2号修改单
Chinese Classification:	C52    Labor sanitation
Professional Classification:	GB    National Standard
Source Content Issued by:	National Health Comission
Issued on:	2024-05-09
Implemented on:	2025-5-1
Status:	valid
Superseding:	GBZ 2.1-2019 Occupational exposure limits for hazardous agents in the workplace— Part 1: Chemical hazardous agents GBZ 2.1-2019/XG1-2022 Occupational exposure limits for hazardous agents in the workplace — Part 1: Chemical hazardous agents|| includes Amendment 1
Target Language:	English
File Format:	PDF
Word Count:	21500 words
Translation Price(USD):	500.0
Delivery:	via email in 1 business day

GBZ 2.1-2019/XG2-2024 Occupational exposure limits for hazardous agents in the workplace - Part 1: Chemical hazardous agents 1 Scope This part specifies the hygiene requirements, determination, evaluation and control principles for occupational exposure to chemical hazardous agents in the workplace. This part is applicable to the hygienic design of industrial enterprises, as well as the management, control and occupational health supervision and inspection of occupational exposure to chemical hazardous agents in the workplace. 2 Normative references The following referenced documents are indispensable for the application of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies. GBZ 1 Hygienic standards for the design of industrial enterprises GBZ 159 Specifications of air sampling for hazardous substances monitoring in the workplace GBZ/T 160(all parts) Methods for determination of toxic substances in the air of workplaces GBZ/T 192(all parts) Determination of dust in the air of workplaces GBZ/T 224 Terms of occupational health GBZ/T 225 Guideline for employer of prevention and control of occupational diseases GBZ/T 229.2 Classification of occupational hazards at workplaces - Part 2: Occupational exposure to chemicals GBZ/T 295 General principles of biological monitoring method in occupational population GBZ/T 300(all parts) Methods for determination of toxic substances in the air of workplaces 3 Terms, definitions and abbreviations For the purposes of this document, the terms and definitions established in GBZ/T 224 and the following ones apply. 3.1 chemical hazardous agents the chemical hazardous agents mentioned in this part include chemical substances, dust and biological agents existing in or arising from the workplace 3.2 occupational exposure the process that workers are exposed to occupational hazardous agents through respiratory tract, skin and mucosa in their occupational activities 3.3 adverse health effects hazardous health efforts or toxic effects of the organism arising from the exposure to occupational hazardous agents. Only a certain level of exposure, i.e. excessive exposure, can cause health damage 3.4 critical adverse health effects the adverse health effects that are used to determine the permissible exposure concentration of certain occupational hazardous agent, i.e. the adverse health effects that are based during the determination of the occupational exposure limits 3.5 occupational exposure limits; OELs the permissible exposure level that the workers are repeatedly exposed to one or more occupational hazardous agents for a long time in their occupational activities, which will not cause adverse health effects on the vast majority of exposed persons. The occupational exposure limits of chemical hazardous agents can include three categories, i.e., permissible concentration-time weighted average, permissible concentration-short term exposure limit and maximum allowable concentration Note: it is a revision of Definition 5.1 in GBZ/T 224-2010. 3.5.1 permissible concentration-time weighted average; PC-TWA the average permissible exposure concentration for 40 h per work week (8 h per working day), specified with time as the weight 3.5.2 permissible concentration-short term exposure limit; PC-STEL the weighted average concentration that allows the workers to be exposed for a short time (15 min), provided that the measured average exposure concentration for 40 h per work week (8 h per working day) meets the requirements of PC-TWA Note: it is a revision of Definition 5.3 in GBZ/T 224-2010. 3.5.3 maximum allowable concentration; MAC the concentration that any chemical hazardous agent shall not exceed within any working day, at any time and at any workplace Note: it is a revision of Definition 5.2 in GBZT 224-2004. 3.6 peak exposures; PE the maximum or peak concentration of a specific substance in the air determined in the shortest analyzable duration (no more than 15 min). For the chemical hazardous agents with PC-TWA but whose PC-STEL has not been established, peak exposures shall be used to control short-time contact. The maximum exposures of PC-TWA is allowed to be exceeded during any short time (15 min) within one working day 3.7 exposure level the concentration or intensity of workers' actual exposure to occupational hazardous agents in the workplace in a specific period of time during their occupational activities, which is detected by a standard determination method Note: it is a revision of Definition 2.22 in GBZ/T 224-2010. 3.8 ratio of occupational exposure level to OELs the ratio of the actual exposure level of workers to certain occupational hazardous agents, to the corresponding occupational exposure limits of the agents When workers are exposed to more than two kinds of chemical hazardous agents, the sum of the measured values of chemical hazardous agents and their corresponding occupational exposure limits is called the ratio of mixed exposure 3.9 action level the workers’ actual exposure level to chemical hazardous agents at which the employers are required to take control measures or actions such as occupational exposure monitoring, occupational health monitoring, occupational health training, and occupational hazard notification, also called administration level or administration concentration The action level of a chemical hazardous agent varies with the workplace environment and the hazardous agents, which is usually half of the allowable concentration of this agent

Contents Foreword i 1 Scope 2 Normative references 3 Terms, definitions and abbreviations 4 Hygiene requirements 5 Monitoring and determination principles and requirements 6 Principles and requirements for occupational exposure control of chemical hazardous agents in workplaces 7 Instructions for proper use of this section Annex A (Normative) Instructions for proper use of this section