APPENDIX F ATMOSPHERIC CONTAMINANTS – Gases or fumes commonly found in excavations are listed in Table 41. Table 41 Origins of gases and fumes Gases or fumes encountered Origin Methane, hydrogen sulphide Peaty ground and decaying organic matter Carbon dioxide, hydrogen sulphide Filled and made ground Carbon dioxide, methane, hydrogen sulphide Reclaimed land and tip fills Natural gas and carbon dioxide City streets, leading gas reticulation pipes Carbon monoxide, carbon dioxide, hydrogen Thermal areas, combustion sulphide, sulphur dioxide, methane Petrol fumes, LPG, kerosene Petrol installation, service stations, underground filling stations Common sources for hazardous atmospheric contaminants are listed in Table 42. Table 42 Origins of other atmospheric contaminants Activity Contaminant Harmful component Hot work Welding or cutting Metal oxides, oxides of nitrogen, ozone, fluorides. fumes Operation of internal Exhaust fumes Carbon monoxide, carbon dioxide, diesel and other combustion engines particulates, oxides of nitrogen, fuel vapours, aldehydes and hydrogen sulphide. Oxygen depletion can occur. Excavation Rock dust Crystalline silica and other mineral dusts. Shotcreting, rock Cement dust or Cement dust, ammonia and chemical accelerating bolting, concreting, accelerator compounds. grouting Battery charging Vapours Flammable gas, acid fumes. Shot firing Blasting fumes Crystalline silica dust, ammonia, oxides of nitrogen, carbon monoxide, sulphur dioxide, carbon dioxide. Table 43 provides a guide to the effects and consequences of some common atmospheric contaminants at various concentrations. Table 43 Effects and consequences of some common atmospheric contaminants
APPENDIX F – ATMOSPHERIC CONTAMINANTS Gases or fumes commonly found in excavations are listed in Table 41. Table 41 Origins of gases and fumes Gases or fumes encountered Origin Methane, hydrogen sulphide Peaty ground and decaying organic matter Carbon dioxide, hydrogen sulphide Filled and made ground Carbon dioxide, methane, hydrogen sulphide Reclaimed land and tip fills Natural gas and carbon dioxide City streets, leading gas reticulation pipes Carbon monoxide, carbon dioxide, hydrogen sulphide, sulphur dioxide, methane Thermal areas, combustion Petrol fumes, LPG, kerosene Petrol installation, service stations, underground filling stations Common sources for hazardous atmospheric contaminants are listed in Table 42. Table 42 Origins of other atmospheric contaminants Activity Contaminant Harmful component Hot work Welding or cutting fumes Metal oxides, oxides of nitrogen, ozone, fluorides. Operation of internal combustion engines Exhaust fumes Carbon monoxide, carbon dioxide, diesel and other particulates, oxides of nitrogen, fuel vapours, aldehydes and hydrogen sulphide. Oxygen depletion can occur. Excavation Rock dust Crystalline silica and other mineral dusts. Shotcreting, rock bolting, concreting, grouting Cement dust or accelerator Cement dust, ammonia and chemical accelerating compounds. Battery charging Vapours Flammable gas, acid fumes. Shot firing Blasting fumes Crystalline silica dust, ammonia, oxides of nitrogen, carbon monoxide, sulphur dioxide, carbon dioxide. Table 43 provides a guide to the effects and consequences of some common atmospheric contaminants at various concentrations. Table 43 Effects and consequences of some common atmospheric contaminants
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