Core Viewpoint - The Ministry of Ecology and Environment has approved four national ecological environment standards aimed at regulating the analysis of particulate matter sources in the air, effective from August 1, 2025 [2][3]. Group 1: Standards Overview - The first standard, "Technical Specification for Open Source Dust Sampling of Ambient Air Particulate Matter" (HJ 1411-2025), is the first release and outlines the technical requirements for sampling open source dust, including soil, road, construction, stockpile, and mixed dust [4]. - The second standard, "Technical Specification for Automatic Weighing of Particulate Matter Filter Membranes" (HJ 1412-2025), also marks its first release and specifies the basic requirements and operational norms for using automatic weighing systems for filter membranes [6][8]. - The third standard, "Ion Chromatography Method for Determining Levoglucosan, Mannan, and Galactomannan in Particulate Matter" (HJ 1413-2025), introduces a method for measuring specific sugars in particulate matter, with detection limits detailed for various sample volumes [10][12][13]. - The fourth standard, "Derivatization/Gas Chromatography-Mass Spectrometry Method for Determining Levoglucosan, Mannan, and Galactomannan in Particulate Matter" (HJ 1414-2025), specifies a method for measuring the same sugars using gas chromatography-mass spectrometry, with detection limits provided for different sample conditions [15][18][20].