Complying with Australian Standards in the workplace is recommended to employees and employers to ensure products and services consistently perform safely, reliably and the way they are intended. When standards are legislated by the Australian Government, it becomes compulsory to follow them. Standards are often revised periodically to ensure its continuing relevance and usefulness.
A Standard that was revised in recent times is the Australian Mining Standard for gas detection in Coal Mines called AS/NZS 2290.3:2018, Electrical equipment for coal mines - Introduction, inspection and maintenance - Gas detecting and monitoring equipment. The primary emphasis of this standard according to Dr Bronwyn Evans, CEO of Standards Australia is to ensure “the safety of coal miners, by providing guidance on the use of gas detection equipment in mines”.
The Pike River Mine Incident on 19th November 2010 in New Zealand shed light on the lack of mine explosion protection standards in Australian and New Zealand underground mines and the risks to miners. This tragic incident which claimed the lives of 29 men was a result of a combination of errors including inadequate methane drainage, non-functioning gas sensors and flawed electrical and ventilation design.
Gas Detection Response Time Testing in Coal Mining
Mining has always been a dangerous occupation. Miners who work underground face a range of potential risks, including asphyxiation, the danger of falling coal and mine explosions caused by methane build-up. There are many toxic gases released in a mining environment, however the most lethal is methane. Methane is a by-product of coal formation. When coal is mined, methane gas is continuously expelled by the coal seams and becomes potentially explosive when mixed with air. Adequate ventilation is extremely important in underground mines to remove and dilute harmful dust and gas from building up.
A more accurate response to a gas leak can potentially save lives by alerting workers of unseen hazards as quickly as possible. Prior to the standards change, all gas detectors were required to be calibrated to the T50 response time test for use in underground mines. The response time T50 refers to the time taken for a gas detector reading to change from 0-50% of the concentration of toxic or flammable gas measured in the environment. The T50 sensor parameter however is considered to be insufficiently accurate for use in hazardous environments such as underground mines. For this reason, the Australian mining standard for gas detection in coal mines has now been updated. It now specifies under Section4.5.2 Inspection /Test Criteria the response time of portable, fixed, transportable and machine-mounted detectors should be tested according to manufacturer instructions for field testing of response times. However, if the manufacturer’s instructions are not provided the following shall apply:
The span gas shall be presented to the detector using the manufacturer’s supplied or recommended fitting to the sensor or sensor head.
The elapsed time between the presentation of the span gas and the detector indicating 90% of the span gas concentration *t(90) shall be recorded.
*t(90) refers to the time it takes for the monitor to display 90 per cent of the actual concentration.
Seamlessly Conduct Response Time Test with the Industrial Scientific DSX Docking Station
Portable gas detectors are the most common types of gas monitoring systems used to protect workers in underground mines. Portable gas detectors such as the Industrial Scientific Ventis MX4, the Ventis Pro5 and the Industrial Scientific Gas Badge are handheld devices capable of measuring and recording gas concentrations upon entry into a work area. The gas detectors used in mining generally contain multiple sensors that can detect and measure a combination of gases such as oxygen, flammable gas, methane, carbon monoxide and other toxic gases.
The Industrial Scientific range of portable gas detectors can be easily calibrated using the DSX Docking Station. It automatically bumps tests and calibrates the portable gas detector upon dock.
The DSX Docking Station can provide response time test results to t(50) and t(90) parameters, therefore, adhering to the latest test criteria for the use of gas detectors in underground coal mines. It also automatically records keeps and provides calibration certificates for compliance reporting.
With the DSX, it is seamless to manage a fleet of gas detectors, ensure the safety of your workers and streamline all gas detector maintenance tasks.
Industrial Scientific’s gas detection range are a proven, tested, and vetted line of products services and solutions. Contact your local Air-Met Scientific representative today to learn more about the Industrial Scientific range of gas detectors and accessories are available for sale and rental at your local Air-Met Scientific office.
