City of London Air Quality
The City of London, also known as the Square Mile, is home to approximately 7,500 permanent residents, 24,000 businesses and has a working population of over 510,000 people. Each year the City of London also welcomes over 10 million tourists.
In 2001, the whole of the Square Mile was declared an Air Quality Management Area (AQMA) for nitrogen dioxide (NO₂) and small particles (PM₁₀). This was due to levels of these pollutants being higher than the required limits.