Support us

ParticulatesChina

Learn traffic rules with clear explanations and visual examples in our illustrated book, designed to make studying simple and engaging.

Traffic signs
Traffic rules
China

62. 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.

Particulates
Smog over Connaught Place at sunset. (Delhi, India)
Wikimedia.org • wili hybrid • CC BY
What are particulates?

Particulates, or particulate matter, are very small solid particles or liquid droplets suspended in the air.

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.

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.

Are diesel vehicles a source of particulates?

Yes. Combustion in diesel engines can produce very small soot particles. Modern diesel vehicles commonly use particulate filters to capture a large proportion of these exhaust particles.

What is a particulate filter?

A particulate filter is an exhaust-treatment device designed to trap particulate matter produced by an engine. Diesel particulate filters are commonly known as DPFs.

Do petrol engines produce particulates?

Yes. Petrol engines can also produce particulate emissions, particularly certain direct-injection engines. Appropriate emission-control systems may therefore include particulate filters.

Do electric vehicles produce particulates?

Fully electric vehicles produce no exhaust particulates from a combustion engine, but particles can still result from tyre wear, road wear and braking.

Are brake and tyre particles regulated?

Vehicle-emission regulation is increasingly addressing non-exhaust emissions. The European Euro 7 framework includes requirements concerning brake-particle emissions and tyre abrasion.

Is particulate matter the same as CO2?

No. Particulate matter consists of tiny airborne particles, while carbon dioxide is a gas. They are different types of vehicle emissions and are regulated for different environmental reasons.

How can vehicle particulate emissions be reduced?

Measures include effective particulate filters, cleaner vehicle technologies, correctly maintained emission-control systems and reductions in brake, tyre and road-wear emissions.

1 China 2 Motorway 3 Expressway 4 Residential area 5 Speed limit 6 Footpath 7 Bike path 8 Tunnel 9 Toll road 10 Slope 11 Bus lane 12 Bus stop 13 Stop sign 14 Give way 15 Roundabout 16 Road narrowing 17 Pedestrian crossing 18 Railway crossing 19 Mandatory direction 20 Turn prohibition 21 School area 22 Rockfall 23 Curve 24 Chevron 25 Wrong-way driving 26 Roadworks 27 Crosswind 28 Height limit 29 Weight limit 30 Radar speed sign 31 Priority at the next junction 32 Traffic lights 33 Traffic lights warning 34 Pedestrian lights 35 Driving licence 36 Location marker 37 Traffic mirror 38 Parking 39 No parking 40 No stopping 41 Disabled parking 42 Reversing 43 U-turn 44 Uncontrolled crossroad 45 Provisional licence 46 Emergency exit 47 Runaway truck ramp 48 Horn 49 Axle weight limit 50 Charging station 51 Pedestrian 52 Motorcycle 53 Car 54 Truck 55 Bus 56 Police 57 Ambulance 58 Taxi 59 Police signals 60 Pothole 61 Path 62 Particulates 63 Air pollution 64 Rush hour 65 Road code 66 Street gutter 67 Cargo bike 68 Forestry vehicle 69 Construction vehicle 70 Semi-trailer truck 71 Trolleybus 72 Speed pedelec 73 Delivery vehicle 74 Idling 75 Tow truck 76 Four-wheel drive 77 Bicycle 78 Motorcycle equipment 79 Rail track 80 Caravan 81 Trailer 82 Tow hitch 83 Fire truck 84 Siren 85 Convoy 86 Emergency vehicle lighting 87 Agricultural machinery 88 Electric bicycle 89 Electric vehicle 90 Pedelec 91 Quadricycle 92 Microcar 93 All-terrain vehicle 94 Van 95 Recreational vehicle 96 Scooter 97 Trikke 98 Personal mobility device 99 Skateboard 100 Segway ...