Legal analysis: 1. "Two Coverages" are the Party's organizational coverage and work coverage. "Fully implement the Central Commission for Discipline Inspection to send discipline inspection institutions to party and state organs at the central level" and "improve the inspection system of the central government, provinces, autonomous regions and municipalities to achieve full coverage of localities, departments, enterprises and institutions". 2. "Six hundred percent" is the countermeasure requirement put forward by the ecological and environmental protection department to curb dust on the construction site. The complete statement is: the construction site should be covered by 600%: the enclosure around the construction site, the closed transportation of muck trucks, the cleaning of vehicles entering and leaving the construction site, the hardening of roads inside the construction site, the wet operation of earthwork excavation and the stacking of materials.

Legal basis: Article 5 (20) of the Three-year Action Plan to Win the Blue Sky Defence War strengthens the comprehensive control of dust. Strict construction dust supervision. Construction sites in key areas should achieve "six hundred percent" of enclosure around the site, material stacking and covering, wet earthwork excavation, road hardening, vehicle cleaning in and out, and closed transportation of muck vehicles, install online monitoring and video monitoring equipment, and network with relevant local authorities.