Starting at $495.00
  • Usually ships in 7-10 business days



  • CO, HCN, NO2, PH3, and SO2 versions available
  • Accuracy:
    • ±5% of reading or ±5 ppm (CO)
    • ±10% of reading or ±5% of full scale (HCN)
    • ±10% of reading or ±5% of full scale (NO2)
    • ±10% of reading or ±5% of full scale (PH3)
    • ±10% of reading or ±5% of full scale (SO2)
  • 5 to 300 hours data logging (adjustable)
  • IP67 rated
  • Intrinsically safe, ATEX and C / US approvals
  • 3 Year warranty

What's in the Box

  • Rubber protective boot
  • Alligator clip
  • Data logging software
  • 2x AAA Alkaline batteries
  • Wrist strap


The RKI Instruments 04 Series single gas toxic monitor is designed to operate for many years with field replaceable sensors and filters. The HCN, NO2, PH3, and SO2 versions can be operated continuously for at least 3,000 hours on (2) AAA size alkaline batteries. The 04 series comes with 2 preset alarms that are adjustable by the end user and also comes equipped with visual, audible, and vibration alarms as standard.

The 04 Series is IP67 rated, meaning it is impact, dust, and water resistant. They are classified as intrinsically safe ATEX/IECEx and by QPS to U.S. and Canadian standards (Class I, Div 1, Groups A, B, C, and D atmospheres).


  • Hazardous material
  • Mining
  • Refineries/petrochemical
  • Water/wastewater treatment
  • Pharmaceuticals
  • Utilities
  • Chemical plants
  • Fire services