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Best Practices - Weekly CO Checks
Repeatable Engine Load Test


Hydrostatic Transmissions

Prepare the Machine for Test
  • Warm up the engine (Emissions change for cold and warm engines)
  • Park the machine into an intake entry with vehicle facing the mine rib
  • Set brakes and chock the wheels
  • Sample exhaust emissions before any after treatment devices, i.e., before catalytic converter, particulate trap, fume diluters, and water scrubber
    • Engine Load Test
  • Make sure no personnel are in front or behind the machine
  • Full throttle, apply load to engine for about 60 seconds
  • Some methods of applying load:
  • Lever to control speed and direction is gradually adjusted until engine speed falls below the engine rated speed
  • Push against mine rib until engine speed falls below the engine rated speed
  • Apply equipment hydraulics until engine speed falls below the engine rated speed
  • Sample allowing reading to stabilize and record measurement
  • Release throttle and shift transmission out of gear
  • Repeat the test using the same method every week for comparable results
  • Sampling with CO measurement device at idle, prior to torque stall, will allow for quicker sampling and shorter stall tests
  • Using a tachometer to verify the engine speed at load will help weekly repeatability
    • Evaluation and Interpretation
  • Check for changes in CO concentration against the baseline you have established for the engine
  • Increases in CO concentration level above the established baseline indicates problems
  • Contact MSHA Technical Support for guidance on engine CO information
  • Maintain records to track engine performance
  • A chart of individual equipment emissions plotted over time (weekly)
  • A logbook separated into individual equipment for easy weekly comparison
  • A logbook separated into similar engines