"GB/T 43905.1-2024 Laboratory methods for soot and gas sampling in welding and related processes, Part 1: Determination of soot emission rates in arc welding and collection of soot for analysis" prescribes laboratory methods for the determination of soot emission rates during arc welding, including steps for collecting soot for analysis. Applicable to all open arc welding except tungsten inert gas shielded arc welding. Instrumentation, materials, test procedures, data processing and reporting requirements are described in detail. It is of great significance for soot control and health and safety of the welding environment.