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Proximity Detection Systems Require Attention Adapted from Information by the Mine Safety and Health Administration The Mine Safety and HealthAdministration (MSHA) has required proximity detection systems (PDS) for continuous mining machines since March 2015. These systems use electronic sensors on both mining machines and miners to detect motion or the location of one object relative to another. The goal is to prevent miners from being struck or pinned by the equipment, by shutting down if a miner is too close. These systems only prevent death and injury if they are properly installed and maintained. Last year, a scoop equipped with a PDS was tramming through a line curtain toward a miner located on the opposite side. Theminer was wearing aminer wearable component (MWC) andwas on his knees, the scoop bucket was in the raised position above the miner, who was able to roll out of the way without being contacted. The scoop operator heard the miner and stopped the scoop. The miner received a broken leg and was immediately transported to the hospital for treatment. MSHA traveled to another mine where a similar PDS was installed on a contin- uous mining machine and observed the PDS was operating erratically. Shutdown zones were found to be set too close to the machine. The machine-mounted com- ponents would only indicate a warning zone infraction when theMWCwas properly indicating it was within the shutdown zone. This allowed the machine to move. In both of these instances, MSHA found the warning and shutdown zones were not set properly and preoperational checks of the PDS were not being conducted in the manner recommended by the manufacturer. To prevent accidents, MSHA suggests following these brest practices: j Ensure PDS systems are installed and maintained in proper operating condition by a trained person. j Conduct preoperational checks by following procedures provided by the PDS manufacturer. j PDS software is updated periodically by manufacturers, make sure these updates are installed regularly. j Verify the warning and shutdown zones are set as recommended by the manufacturer and according to company policy to stop the machine before a miner is contacted. j Ensure both the MWC and the machine-mounted components indicate corresponding warning and shutdown zone status. j MWCs should be checked for physical damage before use. Check for housing cracks or joint separation; broken charging ports or corrosion on the charging terminals; torn gaskets, seals, or membranes on the buttons; cracked or missing windows; broken or inoperable LEDs. The systemmust include audible and visual warnings and cause machines to stop before contacting a miner. Additionally, operators must check the systems before they are used; records of the checks and any corrective actions are also required. )0&"%1 "6)&4 ,, ,, 2)&0 -%3120*"+ )0&"%1 "-% 312., )0&"%1 "-3'"$230&0 .' -&02*" !&+%&% 0*++ */& 3"+ !"++ 0*++ */& !*0&+*-& 0*++ .% "1*-( .,/.1*2& !*0&+*-& 0*++ .%1 .-*$ 0*++ */& "1*-( *21 &0$311*.- "1*-( *21 0*++ .++"01 *1)*-( ..+1 3#1 2"02&0 .%1 "-% 2"#*+*7&01 0*++ */& -$ )*0% 2 8 !*-12&% ).-& 8 8 "5 2., %0*++/*/&*-$ $., 8 444 %0*++/*/&*-$ $., 35 WorldWide Drilling Resource ® JANUARY 2017