WHO guidelines for air quality.
D000393:Air Pollutants / Q000032:analysis*; D000397:Air Pollution / Q000517:prevention & control*; D016902:Air Pollution, Indoor / Q000517:prevention & control; D002248:Carbon Monoxide / Q000032:analysis; D014943:Global Health; D006801:Humans; D007854:Lead / Q000032:analysis; D009585:Nitrogen Dioxide / Q000032:analysis; D010126:Ozone / Q000032:analysis; D013458:Sulfur Dioxide / Q000032:analysis
D000393:Air Pollutants; D013458:Sulfur Dioxide; D007854:Lead; D010126:Ozone; D002248:Carbon Monoxide; D009585:Nitrogen Dioxide