Hello! No Sustainable Development Goal (SDG) is specifically assigned to Air Quality or Clean Air.

https://sdgs.un.org/goals

However, a combination of several SDGs address this issue. Perhaps the following World Health Organization (WHO) website on Air quality, energy, and health will be of some interest to you:

https://www.who.int/teams/environment-climate-change-and-health/air-quality-energy-and-health/policy-progress/sustainable-development-goals-air-pollution

While no Sustainable Development Goal (SDG) is exclusively focused on clean air, the theme is included in many SDGs associated with relevant subjects.

Air quality is an essential element of sustainable development and is included under the following goals:

SDG - 3: Target 3.9

By 2030, substantially reduce the number of deaths and illnesses from hazardous chemicals and air, water and soil pollution and contamination

SDG - 11: Target 11.6

By 2030, reduce the adverse per capita environmental impact of cities, including by paying special attention to air quality and municipal and other waste management

No specific Sustainable Development Goal (SDG) focused solely on clean air exists. Still, it is essential to several goals, particularly SDG 3(Good Health and Well-Being) and SDG 11 (Sustainable Cities and Communities). Clean air is crucial for achieving broader health and environmental targets.