Frequency of Mine Dust Episodes and the Influence of Meteorological Parameters on the Witwatersrand Area, South Africa

Table 3

Determination of dust fall levels by meteorological parameters.

Site code	Regression equation		𝛽 value	𝑅	𝑅^2 (%)	Critical level
34NENT	𝑌df=151.3𝑋ws−339.28	Model 1	150.0	0.41	17	>4 m/s (ws)
40HOSTEL	𝑌df=233.3𝑋ws−618.93	Model 2	235.7	0.58	34	>4 m/s (ws)
50MOLLO	𝑌df=209.2𝑋ws−479.45	Model 3	217.8	0.52	25	>4 m/s (ws)
53-1121	𝑌df=−6.4𝑋rh+570.27	Model 4	−6.35	0.33	11	<60% (rh)
57JCELC	𝑌df=158.1𝑋ws−336.67	Model 5	158.1	0.39	15	>4 m/s (ws)
70CTC	𝑌df=−4.4𝑋rh+526.57	Model 6	−4.41	0.35	17	<50% (rh)
21HR	𝑌df=314.0𝑋ws−803.97	Model 7	314.9	0.47	22	>4 m/s (ws)
23IMP	𝑌df=410.8𝑋ws−1105	Model 8	401.2	0.47	22	>4 m/s (ws)
27PP	𝑌df=7.0𝑋ws−661.96	Model 9	−7.22	0.34	11	<60% (rh)
32KLL	𝑌df=−9.1𝑋rh−148.32	Model 10	−9.13	0.52	15	>4 m/s (ws)
65KG MIN	𝑌df=406.7𝑋ws−678.37	Model 11	406.7	0.40	16	>4 m/s (ws)

Models are significant at 𝑃<0.01.
df: dustfall; ws: mean wind speed. rh: mean relative humidity.