The system, originally given an Intrinsically Safe Evaluation (IS) number of IA13799, is no longer approved as of MSHA’s March 26 bulletin issue date. Officials also noted that Pempek’s request to revoke the application was voluntary.

“In conducting a 2001 recall program of solenoid valves (IA 574-0) used in the Pempek Systems’ evaluated remote control system ABM20, it was determined that a component (inductive coil) used in manufacturing the solenoid was not the same one specified in the MSHA evaluation documentation on file,” the agency said in the PIB.

“To limit the spark ignition hazard, MSHA determined, as a condition of use, the number of solenoids energized at one time should be limited to four of the replacement Rexroth GE-35-2-A solenoid valves, IA-21884. This condition would affect the approval for any machine with a remote control system that used the IA-574 solenoid valve.”

MSHA also noted that this specific Pempek remote control system was never approved for use on any machine or system approved by MSHA as permissible, so there should be no Pempek RC systems in use on such units.

Mines should promptly review equipment inventories for the presence of any Pempek ABM20s and remove machines using the systems from areas requiring permissible products.

Mine operators may request a field modification to use a different remote control system on their equipment, or may consult with their mining machine approval holder for other approved options. If finding a replacement presents an issue, the operator should contact MSHA for further assistance.

The entire version of the PIB can be viewed at