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
