Study Protocol. Evaluating the life-course health impact of a city-wide system approach to improve air quality in Bradford, UK: A quasi-experimental study with implementation and process evaluation

Table 1 Charging clean air zone classes

Vehicle type	CAZ minimum emission standard	CAZ class
		A	B	C	D
Buses and coaches	Euro VI	X	X	X	X
Taxis and private hire vehicles	Euro 6 (diesel) and Euro 4 (petrol)	X	X	X	X
Heavy goods vehicles	Euro VI		X	X	X
Vans and minibuses	Euro 6 (diesel) and Euro 4 (petrol)			X	X
Cars	Euro 6 (diesel) and Euro 4 (petrol)				X
Motorcycles	Euro 3				X

ISSN: 1476-069X