ON-SITE EVALUATION OF DIESEL CONTAMINANTS PRODUCED BY AN ELECTRONICALLY CONTROLLED DIESEL-ENGINE

This research project which took place at Brunswick Mining and Smeltin g's Brunswick mine, was undertaken to assess the ability of new diesel engine technology to meet current and anticipated underground worker exposure limits to diesel exhaust contaminants. Concentrations of CO, CO2, NO, NO2, SO2 and respirable combustible dust (RCD) were measured in a remote mine area where a haulage truck was operating under simula ted duty cycles. The 26 ton haulage truck was equipped with a 300 hp, electronically controlled engine. Fresh air was supplied to the area a s per the MSHA certification document for this particular engine. Resu lts showed that while the vehicle operated in a normal and realistic d uty cycle, the concentrations of contaminants remained well below the ACGIH guidelines for the threshold limit values (TLV) for exposure. Wh ile operating at 63% of maximum horsepower (26 tons of ore in the dump ), the time-weighted average exhaust gases concentrations (CO, CO2, NO , NO2 and SO2) never exceeded 15% of their respective TLVs. RCD concen trations in this instance were measured at 0.59 mg/m3 or 39.3% of the exposure limit suggested by the Canadian ad hoc Diesel Committee. The Air Quality Index was 1.55 or 52% of the maximum suggested value for e xposure.