Simon Worland – Occupational Hygienist
ABSTRACT
Use of compressed air to blow out or “clean” electrical cabinets is a routine maintenance task across the Queensland Coal Industry. Elevated levels of harmful dust can engulf the blow out operator for extended periods and increase the risk of developing lung diseases including Coal Workers Pneumoconiosis and silicosis.
In 2017 the Queensland Mines Inspectorate reported that approximately 50% of all respirable dust and Respirable Crystalline Silica (RCS) exceedances in surface coal mines was directly related to the use of compressed air for cleaning down enclosures and equipment during maintenance activities.
Respiratory protection has historically been viewed as the primary control to protect the health of blow out operators as dust controls at the engineering level or above have not been considered to be feasible.
Blow out of electrical cabinets on Komatsu 960E haul trucks have been targeted for an engineering dust control project at Hail Creek Mine. The project has focussed on the following areas:
• Sealing of cabinets
• Application of positive pressure
• Local exhaust ventilation / vacuuming
• Identification of alternative cleaning methods
• Measurement of control performance
This paper describes the dust control project along future direction for application of common principles to other equipment such as draglines and excavators.
Simon Worland
Caltex
Dr Dave Collins and James Forsyth
Synergetics Consulting Engineers
Use of compressed air to clean electrical equipment is a routine maintenance task in heavy mining equipment (HME) across the Queensland Mining Industry. During cleaning elevated levels of harmful dust can engulf the compressed air cleaning operator for extended periods and increase the risk of developing lung diseases including pneumoconiosis and silicosis.
In 2017 the Queensland Mines Inspectorate (Department of Natural Resources, Mines and Energy, 2018) reported that approximately 50% of all respirable dust and Respirable Crystalline Silica (RCS) exceedances in surface coal mines were directly related to the use of compressed air for compressed air cleaning of equipment prior to maintenance.
Respiratory protection has historically been viewed as the primary control to protect the health of compressed air cleaning operators, as higher order controls such as engineering controls have not been considered feasible.
The principal of applying engineering controls for compressed air cleaning of haul truck electrical cabinets was reported and demonstrated at the Queensland Mining Industry Health and Safety Conference in 2018 (Worland, Stream, Brett and Collins). Here the electrical cabinets were converted into full enclosures under negative pressure resulting in a physical barrier between the worker and the dust generating compressed air cleaning task.
This paper describes the further development and field testing of engineering controls over the intervening 12 months. Safe compressed air cleaning has now been demonstrated for a broad range of HME including trucks, excavators, dragline MG sets and stationary equipment. The controls incorporate continuous monitoring of airborne particulate with feedback systems to shutdown compressed air and demonstrate that safe compressed air cleaning is achievable.
Professor Jianming Wu
Visiting Professor of University of Wollongong and Director of AST Australia
A/Professor Ting Ren</br/>Director of Centre of Infrastructure Protection and Mining Safety, University of Wollongong
Spontaneous combustion (sponcom) of coal remains a major safety issue for underground coal mining operations. Recent heating incidents in Australia further highlight the need of improving current knowledge and practices of sponcom management to ensure safety and productivity of coal mines extracting coal seams that are prone to spontaneous heating.
This presentation will provide some the fundamental theory and practices in the early detection, prevention and control of spontaneous combustion of coal. Case studies based on Chinese and Australian coal mines will be presented to demonstrate a range of techniques, including radon detection, jel and fly ash injection materials, that can be practically used for coal heating and fire management.
The presentation will also include studies of goaf gas flow dynamics based on computational fluid dynamics (CFD) modelling. Based upon fundamental fluid flow governing equations, computational models are developed to investigate the impact of different ventilation layout and ventilation parameters on goaf gas flow characteristics and in particularly, oxygen leakage and ingress patterns, and hence identification of high sponcom risk zones. Inertisation strategies, using both nitrogen and carbon dioxide, are modelled to optimise operational parameters (e.g, injection flow rate and location etc) for active longwalls and seal-off operations.
Christian Young, Founder, Managing Director, Impress Solutions
Christian Young,
Impress Solutions
Christian Young
Managing Director, Impress Solutions Pty Ltd
Safety Differently describes a movement within the safety community to change the perspective of organisations in three key areas – the definition of safety, the role of people, and the focus of the organisation.
Traditional or “normal” safety management tends to view these three areas in this way:
- Safety is defined as an absence of negatives (e.g., accidents, unacceptable risk, unsafe acts, etc.)
- People are a problem that must be controlled
- The organisation focuses on safety as a bureaucratic accountability to those above us hierarchically
By contrast, Safety Differently views these three key areas this way:
- Safety is defined by the presence of positives, such as a capacity to be successful in varying conditions
- People are the solution
- The organisation focuses on safety as an ethical responsibility to those who do the organisation’s messy, risky work
Safety Differently is an approach used by organisations who wish to move beyond traditional safety management.
Through the lens of Safety Differently organisations can evaluate their existing strategies and look for opportunities to alter course. This presentation will further discuss how Safety Differently can be applied within the mining context.
Prof Graeme Zosky, Deputy Director, Menzies Institute for Medical Research, University of Tasmania