Digital private mobile radio (PMR) can enhance safety and efficiency for workers in the resources sector.
Putting safety first Digital private mobile radio (PMR) - such as TETRA (Terrestrial Trunked Radio) and APCO-25 (P25) - can significantly help the resources industry reduce human error, particularly at the intervention stage when it can have a dramatic impact on business activities and public and employee safety. Its first role is in the early prevention or identification of faults. Modern oil refineries and petrochemical plants are awash with sensors and meters, measuring pressures, tank levels, emissions and so on. Digital PMR is the ideal solution for industrial telemetry: modules can wirelessly connect sensors to control rooms, with the robustness and reliability of a wired network. By using digital PMR, an operator can rapidly
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deploy new sensors without the need to provide new cabling. In hard-to-reach locations, this alone helps to reduce safety issues. Digital PMR telemetry has already been used to monitor electricity grid infrastructure in Australia (Ergon Energy) and Spain, and provide vital signs monitoring in some UK ambulances. But it’s not enough to simply monitor equipment remotely. When alarms are triggered, or meters have faults, maintenance engineers need to be dispatched, and they need a reliable solution for relaying the results or their investigations to the control room. Again, PMR can enable this with the use of electronic forms on a PMR-based PDA. Readings from meters can be input into the device on the spot and immediately sent to the control room over the air. The alternatives are not attractive: either the engineer must call their report in, which can introduce errors in transposition, or they can batch process their results when they return to the administrative section. Neither option is as efficient or safe as the ability to instantly and automatically update the control room on alarm faults.
Supporting lone workers Industry regulations governing site safety require that resources companies be acutely aware of the personal safety of staff at mines, plants, tank farms and refineries. On these vast sites, with dangerous chemicals and exposed working places, many maintenance engineers are lone workers and exposed to countless hazards in the working day. The onus is increasingly on employers to ensure that workers’ safety is guaranteed as much as possible. Again, digital PMR can help in a number of ways. Firstly, PMR equipment is intrinsically safe and so guaranteed not to spark a fire. This is not necessarily the case with other mobile, wireless and fixed-line handsets. If you are working in an environment with potentially flammable vapours, this is a very important feature. Secondly, there are digital PMR solutions that allow both passive and active
AUGUST/SEPTEMBER 2014 - SAFETY SOLUTIONS 5
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xplosions at oil and gas plants or mine sites and toxic gas leaks at petrochemical plants can cause widespread damage to equipment, lost revenue, environmental damage, brand damage and, in the worst cases, injuries among employees and in the neighbouring area. And there can be a considerable impact on the local communities both during and in the aftermath of an incident. To prevent these incidents happening, the resources industry has some of the strictest regulations regarding fire, explosions and gas leaks. And yet the principle cause of most disasters and failures is human error or failing to intervene correctly when the first alarms are signalled. For instance, if pressure builds in a tank but human error leads to a failure to vent the tank, pressure can build further leading to a boiling liquid expanding vapour explosion (BLEVE). The catastrophic disaster on Piper Alpha in 1988 was exacerbated by human error - one shift did not communicate effectively with the next shift. Human error has also been linked to incidents at ESSO’s natural gas plant explosion at Longford in Victoria’s Gippsland region, Flixborough (UK), Seveso (Italy) and Toulouse (France). Each time, new regulations are introduced to tighten up or create new safe processes.