How is medium toxicity defined?

This post was last edited by bfdlwolf on 2019-11-29 at 12:46. I. In the announcement issued by the General Administration of Quality Supervision, Inspection and Quarantine and the Standardization Administration Committee (No. 6 of 2017), titled “Announcement on the Abolishment of 396 Mandatory Standards”, “Classification of the Hazards Caused by Occupational Exposure to Toxic Substances” (GB 5044-1985) is also among those being abolished. This standard has troubled everyone for a long time; it has finally been officially abolished. Why doesn’t GBZ 230 explicitly state that “this standard replaces GB5044”? Because GBZ230 is an industry standard, and industry standards cannot replace national standards. Second, the \"Code for Design of Industrial Metal Piping\" GB50316-2000 is also likely to be revised. GB 5044-1985 has been repealed; GBZ 230 should be followed instead. III. The \"Announcement by the State Administration for Market Regulation on Matters Related to Administrative Licenses for Special Equipment\" (No. 3, 2019) classifies industrial pipelines as follows: GC1 grade: 1. Process pipelines that transport media with acute toxicity of Category 1 as specified in the \"Catalogue of Hazardous Chemicals\", gas media with acute toxicity of Category 2, and liquid media with acute toxicity of Category 2 whose operating temperature is higher than their standard boiling point ； 2. Process pipelines that transport flammable gases of Class A or B, or flammable liquids of Class A (including liquefied hydrocarbons), as specified in GB50160 \"Code for Fire Protection Design of Petrochemical Enterprises\" and GB50016 \"Code for Fire Protection Design of Buildings\", and whose design pressure is 4.0 MPa or higher ； 3. Process pipelines that transport fluid media, with a design pressure of 10.0 MPa or higher, or a design pressure of 4.0 MPa or higher along with a design temperature of 400°C or higher. GC2 grade: 1. Process pipelines other than GC1 grade; 2. Refrigeration pipelines. GCD grade: Power pipelines. The following changes have been made: 1. The definition of GC1(1) grade pipelines has changed. GC1(1) class pipelines: “Process pipelines that transport media with an acute toxicity level classified as Category 1 as specified in the Catalogue of Hazardous Chemicals, gas media with acute toxicity in Category 2, and liquid media with acute toxicity in Category 2 whose operating temperature is above their standard boiling point”, rather than “pipelines that transport media with an extremely hazardous toxicity level, highly hazardous gas media, and highly hazardous liquid media whose operating temperature is above their standard boiling point”. 2. The toxicity level of the media is determined according to the acute toxicity categories specified in the Catalogue of Hazardous Chemicals, rather than according to the provisions of GB5044-1985 on the classification of hazards associated with occupational exposure to toxic substances. 3. The scope of GC2 grade was expanded; refrigeration pipes and the previously classified GC3 pipes were included under the GC2 grade, while the GC3 grade was abolished. 4. A GCD grade, namely power pipes, was added. Pressure pipelines should be classified according to the acute toxicity category of the medium specified in the Catalogue of Hazardous Chemicals.

How are refrigeration pipes defined?