Underground » Health and Safety
The objective of the study was to develop, test and prove up under mine conditions a Diesel Particulate Matter (DPM) real time atmospheric monitoring unit. The design for the new instrument, termed the D-PDM, is based on the recently developed real time respirable dust PDM. The project's main activities were to undertake through internationally recognised laboratory testing an evaluation of the new design and to undertake a comprehensive underground series of tests to establish the robustness and reliability of the new approach.
The phases of design, the international laboratory testing and the underground mine evaluation in five operating mines proved that the monitor is capable in normal mine atmospheres of accurately measuring DPM levels in real time. The monitor has successfully reported data when used as a static or stationary instrument, when placed within the cab of a moving vehicle and when worn on a person's belt. The outcomes of the project provide the industry access to an enhanced tool for understanding the presence of DPM in the mine atmosphere.
Throughout the D-PDM mine testing phase SKC comparison tests were undertaken as the only other approach available in Australia for measuring mine atmosphere DPM. The SKC system results were analysed for carbon and give EC and TC readings from DPM samples. Analyses from all mines' test series compared with SKC impactor collection determinations for EC and TC taken in the particular mine at the same time showed close correlations were found for all cases. These results gathered over many testing circumstances, mines and mine situations demonstrate the validity of the D-PDM monitor as a very significant contribution to the accurate understanding of DPM levels in mines. An important point is that the results demonstrate that calibration relationships vary mine to mine. This is to be expected and is due to differences in aspects such as mine atmospheric contamination, vehicle fleet variations, fuel type, engine maintenance and engine behaviour.
The project has extended some recommendations on the need for greater understanding of the complexities of DPM in the mine atmosphere. It has suggested a future application of the DPDM to use in conjunction with “tracker” systems in replacing the current “tag” boards with a system that measures the diesel pollutant load within the mine panel and can direct placement of vehicles accordingly. It has, in addition, suggested other uses for the D-PDM in evaluating in the underground environment various mine control, exhaust system and fuel compositions. The project proved up the concept of a real time DPM monitoring instrument. It provides an alternative to the SKC shift average monitoring system. The D-PDM unit gives real time evaluations and so is very powerful in allowing understanding of DPM emission patterns in the fast changing mine production cycle and in undertaking engineering evaluation exercises. The objective testing over a number of different approaches and the comparisons with the SKC monitoring approach lead to the conclusion that the D-PDM is accurate when compared to existing measurements from the SKC method.