Riken Keiki RKI RI-85, Portable Infrared CO2 Gas Monitor


Riken Keiki Logo


RI-85 Portable Infrared CO2 Gas Monitor (Discontinued – GX-6000 is recommended)

This Model RI-85 is a compact, lightweight portable CO2 monitor with an Infrared (NDIR) type sensor. This sensor provides fast and accurate detection of CO2 levels from 0 to 10,000 ppm. An internal pump is utilized for continual sampling, and the unit operated for 12 hours from one set of batteries. Microprocessor control provides average readings over a selected time period, and also can display the peak value detected.

Microprocessor controlled
Instantaneious, Peak, and Average values provided
Compact and Lightweight
Audible and visual alarms
Internal sample drawing pump
LCD digital display with backlighting
Recorder output signal (0-1V linear)


Indoor air quality CO2 level testing
Safe CO2 breathing levels in plants or factories
Leak checking on CO2 fire extinguisher equipment
Check before intering after CO2 extinguisher use.
Exhaust gas leak from combustion appliances in homes or plants

RKI RI-85 Quick Specification

Category Portable gas detector
Type Single gas
Target gas Carbon dioxide
Detection principle NDIR
Detection range 0-10000ppm (Option: 0-50000ppm)
Sampling method Sample draw
Type of alarm Gas alarm, Trouble alarm
Display of alarm Flashing light, buzzer
Power source AA size dry battery x 4 pcs.
Continuous operation 12 hours (Alkaline batteries, no alarms or no illumination, room temp.)
Dimensions & Weight 85(W) x 190(H) x 40(D) mm (3.5″W x 7.8″H x 1.6″D), Approx. 500g
Operating temperature & Humidity -10 to 40oC (14 to 104oF), Below 90%RH


Riken Keiki

The RIKEN KEIKI (KRI) product lineup includes more than 100 types of gas detectors and environmental monitoring products. Riken Keiki (RKI) Single gas detector range: 
  • 03 Series Smallest Single Gas Monitor
  • GasWatch 3 – Smallest Gas Monitor
  • 04 Series Smallest Toxic Gas Monitor
  • FP-31 Formaldehyde Gas Detector
  • SP-220 Gas Leak Checker for Combustible, Toxic, Freon and Fumigation Gases
  • SC-8000 Portable Toxic Gas Monitor
Riken Keiki (RKI) Multi-gas detector range: 
  • GX-3R Personal Gas Detector
  • GX-3R Pro Gas Detector with Wireless Communication
  • GX-6000 PID Gas Monitor
  • GX-2012 Confined Space Gas Monitor
  • GX-2009 Portable Multi Gas Detector
  • Gas Tracer PPM Leak Detector
  • Eagle 2 Multi Gas Detector for LEL, O2, H2S, CO, VOC & Toxics
  • Eagle Gas Detector
Riken Keiki Logo


Detection Principle
Non-Dispersive Infrared Detection (NDIR)
Measuring Gas Carbon dioxide (CO2) in air
0-10,000 ppm
Resolution 10 ppm/digit from 0-2,000 ppm,
25 ppm/digit
from 2,000-5,000 ppm,
50 ppm/digit
from 5,000-10,000 ppm
Sample drawing with internal pump
Repeatability + / – 3% F.S. (with constant conditions)
Alarm Display Audible and visual alarms (non-latching)
Alarm Point Any one level selection of 1,000 ppm, 5,000 ppm, or OFF
Response Time Within 15 seconds to 90% response
Operating Temp.
& Humidity
-10 ~ 40°C (14 ~ 104°F), below 90%RH
Power Source AA size Alkaline batteries (4 pcs.)
Approx. 12 hours (With no alarm or backlight, with alkaline batteries at room temperature)
Dimension Approx. 85mm(W) x 190mm(H) x 40(D)mm,
3.5″(W) x 7.8″(H) x 1.6″(D)

500g, 1.1 lb.
Display Current reading, Average value, or Peak reading
Pushbutton select
Average Value Time Selected from 1 minute, 3 minutes, or 15 minutes
External Output Signal 0-1v DC linear output
  • Carrying case
  • Spiral tube (1m)
  • Gas sampling probe
  • Absorption tube for zero adjust
  • AA size alkaline batteries
  • Operating manual
  • Gas cylinders for zero and span calibration
  • Sample bag
  • Absorptive agent for zeroing
  • Jack for external output

Specifications subject to change without notice.


There are no reviews yet.

Be the first to review “Riken Keiki RKI RI-85, Portable Infrared CO2 Gas Monitor”

You may also like…