Model 42i (NO-NO2-NOx) Analyzer

Measure levels of nitrogen oxide (NO-NO2-NOx) in the emissions from a source using chemiluminescent technology with the Thermo Scientific™ Model 42i NO-NO2-NOx Analyzer.

Discover the iQ to work smarter with our next-generation 42iQ NO-NO2-NOx Analyzer.

Key Features:

  • Standard dual range and auto ranges
  • Five-second response time
  • Temperature and pressure correction
  • User settable alarm levels for concentration

iSeries Advantage:

  • Ethernet connectivity for efficient remote access
  • Enhanced user interface with one-button programming and large display screen
  • Flash memory for increased data storage and user-downloadable software
  • Enhanced electronics design optimizes product commonality
  • Improved layout for easier accessibility to components

The Model 42i NO-NO2-NOx Analyzer is also available with an oxygen sensor module.

Using paramagnetic sensor technology the Model 42i with Oxygen gives the source measurement of NOx extended capabilities to read and report the concentration of oxygen in the sample stream up to 100%. Additionally, programming allows the user to correct the NO, NO2, and NOx reading for the amount of oxygen in the sample.



Flow Rate0.6 L/min.
Inputs16 Digital Inputs (Standard), 8 0 to 10 VDC Analog Inputs (Optional)
Response Time40 sec. (10 sec. average time), 80 sec. (60 sec. average time), 300 sec. (300 sec. average time)
Span Drift±1% full scale (24 hr.)
Temperature (English) Operating59°F to 95°F
Temperature (Metric) Operating15°C to 35°C
Zero Noise0.2 ppb RMS
Certifications/ComplianceETL, CSA, UL, CE; U.S. EPA, European (TUV), MCERTS, NF (France), UKCA
Depth (English)23 in.
DescriptionNitrogen Oxide Analyzer
Height (English)8.62 in.
Measurement RangePreset Ranges: 0 to 0.05, 0.1, 0.2, 0.5, 1, 2, 5, 10, 20, 50 and 100 ppm or 0-0.1, 0.2, 0.5, 1, 2, 5, 10, 20, 50, 100 and 150 mg/m3; Custom Ranges 0-0.05 to 100 ppm or 0 to 0.1 to 150 mg/m3; Lower Detectable Limit 0.40 ppb (60 second averaging time)
OutputsSelectable voltage, RS232/RS485, TCP/IP, 10 status relays, and power fail indication (standard); 0 to 20 or 4 to 20 mA isolated current output (optional)
Precision±0.4 ppb (500 range)
Weight (English)55 lb.
Weight (Metric)25 kg
Width (English)16.75 in.
Width (Metric)425.45 mm
Zero Drift<0.40ppb/day
Unit SizeEach