• Air pollution in the CMA is trapped by inversion layers. These climatic conditions often coincide with early morning peak traffic conditions, causing visible levels of air pollution in the form of a white or brown haze.

• Pollution haze results from increasing vehicle usage and in particular emissions of nitrogen dioxide, sulphur dioxide and small particles of dust (PM₁₀ and PM_2.5) (see Transportation).
• These emissions result from increasing vehicle usage and in particular diesel vehicles, but also wood fires and burning tyres. Increasing vehicle usage and trip lengths result from urban sprawl and poor public transport (see Urbanisation and Infrastructure)
• Vehicle numbers have increased by 80% in the CMA in the last 20 years.
• Legislative measures to control air pollution from industry and vehicles are inadequate. Diesel Vehicle Control is limited to naturally aspirated engines whereas most new diesel vehicles are turbo assisted and excluded from legislation.

• Diesel vehicles contribute 48% of particulate air pollution.
• Current car ownership is about 170 cars per 1000 population.
• The average age of vehicles on the road is increasing.
• Guideline levels of nitrogen oxides (NOx), sulphur oxides (SOx), particulate matter (PM₁₀ and PM_2.5) are approached or exceeded with increasing frequency.
• Scheduled industries are controlled by DEAT which is understaffed and not in a position to apply necessary pressure, enforcement and monitoring of these industries.
• Approximately 14% of households in the CMA do not have electricity.

• Air Pollution Control section of the Directorate: Protection, Health and Trading, CMC:  Exceedances of WHO and UK guidelines for SOx, NOx, PM₁₀, O₃, NMHC, UV, H₂S, Pb and VOC’s.   

• Directorate: Corporate Services, CMC: Number of (un)electrified homes  

• See Transportation indicators  

• See a summary of all Indicators on this website

• A diesel vehicle testing and emissions control is being undertaken in association with MLCs.
• Strict controls are being enforced on industry.
• The Cape Metropolitan Transport Plan, known as "Moving Ahead" is being revised.
• National government is being pressured to replace outdated national air pollution legislation. Existing Air Pollution Control Legislation dates back to 1965 and is in serious need of revision to meet current and future air pollution control needs.
• The Department of Transport has been approached to include vehicle emissions testing in existing compulsory vehicle testing procedures.

Additional responses underway:

• A comprehensive study, Cape Town Brown Haze Study, which determines the causes of brown haze was undertaken by UCT’s Energy Research Institute for the CMA to which the CMC contributed.
• The Constitution (Act 108 of 1996) assigns air pollution control to be a local government responsibility. The CMC is in the process of establishing systems and skills needed to effect this responsibility.

• Whenever possible, make use of public transport or non-polluting modes of transport, e.g. bicycle.
• Report smoking vehicles to the CMC’s Air Pollution Control Division.
• Keep your motor vehicle in good running condition.
• Drive a fuel-efficient car.