Table 3.

Correlation (r value) between parameters at the sampling stations

Stations	Parameters	PM10	CO	NO2	O3	SO2
Petaling Jaya (S1)	PM10	1
	CO	−0.016	1
	NO2	0.152	0.065	1
	O3	0.068	−0.490**	0.035	1
	SO2	0.117	0.595**	−0.077	-0.337**	1
Shah Alam (S2)	PM10	1
	CO	0.590**	1
	NO2	0.649**	0.549**	1
	O3	0.343**	0.323**	0.147	1
	SO2	0.127	0.220*	-0.111	-0.152	1
Gombak (S3)	PM10	1
	CO	0.505**	1
	NO2	0.523**	0.625**	1
	O3	0.472**	0.440**	0.441**	1
	SO2	0.352**	0.343**	0.195*	0.207*	1
Jerantut (B)	PM10	1
	CO	0.611**	1
	NO2	0.424**	0.267**	1
	O3	0.417**	0.391**	0.530**	1
	SO2	-0.226*	0.054	-0.131	-0.138	1

** Correlation is significant at the 0.01 level (2-tailed)

* Correlation is significant at the 0.05 level (2-tailed)