Impact of ISO 14001 Environmental Management System on Key Environmental Performance Indicators of Selected Gold Mining Companies in Ghana

Table 2

Ambient noise levels from 2003 to 2009 at GFGL.

Year	Mean; (dB)	Maximum; (dB)	Minimum; (dB)	EPA guideline value; (dB)
2003	48.76	59.1	44.6	65
2004	51.32	55.82	45.36	65
2005	62.66	72.9	56.2	65
2006	54.75	58.8	51.9	65
2007	38.9	45.5	32.2	65
2008	33.04	34.7	32	65
2009	49.17	60	35	65