Industrial air quality manufacturer keeps it in the family as Helder Armas takes over as president.
Good days in which air quality was rated good grew by 19 to 107.
Researchers find brief, dramatic spikes in levels of benzene, a known carcinogen for which there is no safe level.
Energy company was monitoring air quality when tests revealed sulphur dioxide levels were below guidelines.
Equipment monitors air quality during environmental emergencies.
US presses ahead with tough requirements for new coal-fired power plants.
Good for career but bad for health: How expats see a stint in China.
Report cites high consumption and throwaway habits for a C grade.
Agreement updates air quality standards for the first time in 20 years, starting with sulphur dioxide, nitrogen dioxide and volatile organic compounds.