ParticulatesPortugal
32. Particulates
Particulates, or particulate matter (PM), are tiny solid particles or liquid droplets suspended in the air. In road traffic, particulate emissions can come from vehicle exhaust, brake wear, tyre wear and road-surface wear, as well as dust that is disturbed by passing traffic.
Particulate matter is commonly classified by particle size. PM10 refers to particles with a diameter of up to approximately 10 micrometres, while PM2.5 refers to finer particles of up to approximately 2.5 micrometres. Vehicle emission standards, particulate filters and air-quality measures are used to reduce exposure to these pollutants.
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What are particulates?
Particulates, or particulate matter, are very small solid particles or liquid droplets suspended in the air.
🔗 epa.gov • US EPA, Particulate Matter Basics
🔗 fhwa.dot.gov • US FHWA, particulate matter and road-transport sources
🔗 epa.gov • US EPA, AP-42 section 13.2.1.1, paved-road emissions and dust resuspension
What are PM10 and PM2.5?
PM10 refers to particles with a diameter of up to approximately 10 micrometres. PM2.5 refers to finer particles with a diameter of up to approximately 2.5 micrometres.
🔗 epa.gov • US EPA, Particulate Matter Basics
🔗 fhwa.dot.gov • US FHWA, particulate matter and road-transport sources
🔗 epa.gov • US EPA, AP-42 section 13.2.1.1, paved-road emissions and dust resuspension
Where do traffic particulates come from?
Road traffic can produce particles through engine exhaust, brake wear, tyre wear and road-surface wear. Passing traffic can also resuspend dust already present on the road.
🔗 epa.gov • US EPA, Particulate Matter Basics
🔗 fhwa.dot.gov • US FHWA, particulate matter and road-transport sources
🔗 epa.gov • US EPA, AP-42 section 13.2.1.1, paved-road emissions and dust resuspension

Traffic rules
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