Alpha MOS Environment

- Model SM110C - Ultra Portable Olfactometer


SM110C is an in-field odour-measuring device that allows users to accurately quantify ambient odour strength. Easy to use, it improves the reliability of odour assessments in the field. This revolutionary device offers a cost-effective alternative to laboratory measurements, often costly and not always required. When lab results are not required, this versatile olfactometer facilitates the calibration of RQ Box e-noses. Robust and accurate, this instrument meets the EN13725 and ASTM E679 standards for olfactometer design.

  • Collection of gas emissions samples from various types of sources: ambient air, smoke stack, air vent, etc.
  • Pre-dilution of gas samples in TedlarTM or NalophanTM bag
  • Odour assessment by sensory analysis (2 to 30 000 OU)
    • Field analysis of ambient air
    • Field or laboratory analysis of air in sampling bag, collected from flux chamber, lung sampler, etc.
    • Concentration in odour unit (OU) or Dilution to Threshold ratio (D/T)


The SM110C dilutes the air sample with fresh odourless air at a known and repeatable dilution ratio. It draws the sample of ambient air via venture pump and dilutes it using fresh odourless air from a compressed air tank. An adjustable sliding valve is used to control the ratio of fresh to ambient air. When odour becomes detectable, the operator reads the sample strength (OU or dilution to threshold) from the valve position indicator.

  • Conduct odour emission assessment in the field
  • Rank emission sources
  • Calibrate the RQ Box e-noses on site
  • Determine odour mitigation effectiveness over time
  • Verify dispersion model predictions
  • Conduct panelist screening using n-butanol kit

Robust and accurate

  • Portable and self-contained instrument
  • Wide range of detection, from 2 to 30 000 OU
  • Meets EN13725 and ASTM E679 for olfactometer design

Reliable results

  • Dilution with clean and odorless air from a lightweight bottle integrated into a backpack: no risk of ambient cross contamination
  • Keeps nose sensitive even in the harshest ambient odours
  • Comparable results to full scale odour laboratories

Cost effective and faster on-site calibration of RQ Box e-noses when laboratory measurements are not required

  • Direct sampling and on-site odour assessment, close to the RQ Box e-nose.
  • No risk of sample degradation caused by shipment as is the case for delayed olfactometry
  • Reduced costs, higher frequency of measurement possible

Easy maintenance

  • No contamination: Teflon nose masks, stainless steel wetted surfaces
  • No pump or other moving part to maintain
  • Does not require frequent re-calibration