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IAQ-Calc Indoor Air Quality Meter

IAQ-Calc Indoor Air Quality Meter



TSI's 7545 IAQ-CALC Meter is an outstanding instrument for investigating and monitoring indoor air quality (IAQ). The 7545 model simultaneously measures and data logs multiple parameters. Measurements are CO, CO2, temperature, humidity; and calculations are dew point, wet bulb temperature, and % outside air.

The proprietary TSI LogDat2 software permits easy transfer of data to a computer. Data can be reviewed on-screen, or downloaded to a computer for easy report generation. Statistics function displays average, maximum and minimum values, and the number of recorded samples.

Features & Benefits

  • Low-drift NDIR CO2 sensor for stable, accurate readings
  • Temperature and relative humidity measurements help determine thermal comfort
  • Directly calculates dew point and wet bulb temperatures
  • Electrochemical sensor measures CO
  • Calculates % outside air from either CO2 or temperature
  • Displays up to three parameters
  • Logs up to 26,900 data points with key (4) measured parameters enabled
  • Sampling function records multiple point measurements


  • Verify building HVAC system performance
  • Examine building IAQ conditions to optimize worker productivity
  • Comply with regulations and guidelines


Technical Specifications

Product Specifications Description
Operating Temperature 32 to 113°F (0 to 45°C)
Storage Temperature -4 to 158°F (-20 to 70°C)
Logging Capability (Models 7525 and 7545) Model 7525 logs up to 24,200 data points with all measured parameters enabled
Model 7535 logs up to 40,300 data points with all measured parameters enabled
Model 7545 logs up to 22,000 data points with all measured parameters enabled
Time Constant 1 sec, 5 sec, 10 sec, 20 sec, 30 sec (user selectable)
Log Intervals 1 second up to 1 hour (user selectable)
Meter Dimensions (all models) 4.2 in. x 7.2 in. x 1.5 in. (107 mm x 183 mm x 38 mm)
Probe Dimensions (Model 7515) Length: 2.7 in. (69 cm)
Diameter: 0.76 in. (2.0 cm)
Probe Dimensions (Models 7525, 7535, and 7545) Length: 5.9 in. (15.1 cm)
Diameter: 0.74 in. (1.9 cm)
Weight (with batteries) Models 7515 and 7535: 0.6 lbs (0.27 kg)
Models 7525 and 7545: 1.16 lbs (0.53 kg)
Power Requirements Model 7515 Four AA-size batteries
Models 7525, 7535, and 7545
Four AA-size batteries or AC adapter