Stack Effluent Monitoring


Flow Monitoring

We supply numerous flow measurement solutions for ventilation systems, ranging from simple pitot devices to complete arrays.

Features and benefits:

  • Yokogawa EJX 120 Differential Pressure Transmitter
    • When paired with a Pitot tube this differential pressure transmitter covers all the flow measurement requirements for low flow applications.
  • Tried and tested technology
  • Bespoke designs available
  • Various mounting options
  • Good accuracy
  • Long life
  • Low maintenance

Gaseous Sample & Return Probes


The Gaseous Sample & Return Probe provides a simple solution for gas sample extraction from a stack/duct.

Features and benefits:

  • Simple design
  • Easy installation
  • One stack penetration required for sample and return

Datasheet – Universal Mounting Flange

Isokinetic Sample Probes


We offer a range of isokinetic sample probes, designed to extract a representative sample of particulate from an effluent duct or stack. The sample probe can be used in conjunction with one of our range of Continuous Air Monitors, or with a Static Air Sampler (SAS).

Datasheet – Isokinetic sample probe

Shrouded Probes

The Shrouded Sampling Probe for extracting particulate matter from stacks and ducts at a range of velocities.


  • Lower Internal wall losses
  • Better off-angle performance
  • Low sensitivity to flow stream turbulence
  • Can operate in either fixed or modulating flow rates
  • The Shrouded Probe can operate over a range of flow rates
  • Complies with the requirements of ANSI N13.1-2011 Sampling and Monitoring Releases of Airborne Radioactive Substances from the Stacks and Ducts of Nuclear Facilities

Datasheet – Shrouded Probe

PET Cyclotron Facility Stack Monitoring

The Positron Gas Stack Monitor provides continuous monitoring of effluent discharges from cyclotron (and other positron gas users) facilities.


  • Designed to provide fast response to positron gas concentration, the CMS-PET system will provide a display of concentration (Bq/m3 or PCi/ml) and volumetric stack flow (m3/sec or CFM).
  • The CMS PET Stack monitor can be networked to a facility control centre computer for remote monitoring, alarm annunciation, historical data collection and reporting function. See the 9205PET for more information on this package.


Stack and Duct Sampling and Real-Time Monitoring

We have the capability to survey, design, supply, install and commission stack and duct sampling and real time monitoring systems. The complete system can be tailored made to suit each customer’s individual site needs, with the number and type of samplers /monitors varying from project to project.

Noble Gas Monitor – CMS Noble Gas

The Noble Gas Monitor is an integrated solution for the measurement of the airborne concentration of radioactive (beta emitting) noble gases.

Key points of performance include:

  • Excellent MDL resulting from minimal detector response to external sources of gamma.- Low response to NORM such as radon and thoron.
  • Available in a fixed or transportable configuration.
  • CMS analysis algorithm provides a low stable measurement at background, but ensures a fast response to rising concentration levels.
  • Optional gamma dose-rate detector for dynamic gamma background compensation or dose rate measurement.

Datasheet – CMS Noble Gas Monitor

Inline Filter Holder

The Inline filter holder is suitable for use with card mounted filters of either 25 mm or 40 mm diameter.

Features and benefits:

  • Suitable for 25 mm or 40 mm filter cards
  • Filter card can be changed without interfering with the vacuum line
  • Inline filter holder with either 10 mm or 25 mm inlet
  • Full stainless steel construction

Iodine Monitor – CMS Iodine

The CMS Iodine is an advanced system for monitoring airborne concentration of radioiodine in the workplace and other areas of interest (stacks, cells and glove boxes).

Key points of performance include:

  • Automatic background compensation.
  • Filtration mechanism captures all forms of radioiodine.
  • Achieves low MDL’s through unique detector design with Brehmstrahllung shield.
  • Temperature spectrum stabilization reduces inaccurate measurement due to spectrum drift.
  • CMS analysis algorithm provides a low stable measurement at background, but ensures a fast response to rising concentration levels.

Digital Air Flow Calibrators

Digital air flow calibrators are accurate devices designed for the calibration of all types of air samplers and continuous air monitors.


  • Differential pressure flow sensor
  • Display of flow in CFM, LPM or M3/min. by operator selection
  • Standard accuracy: ±2.0% Full Scale
  • Flow rates displayed are corrected to a factory settable
  • Reference Temperature and Pressure (4 options available)
  • Classical STP 0 °C, 1 Atm
  • Normal T and P 20 °C, 1 Atm
  • Modified Normal T and P 70 °F, 1 Atm
  • Standard ambient T and P 25 °C, 1 Atm
  • Display of barometric pressure in metric or English units
  • Display of temperature in metric or English units
  • Portable battery operated unit is available
  • Certified to UL, CSA and CE electrical safety standards
  • NIST traceable calibration certificate
  • Ambient or reference flow is selectable by the operator
  • Two year warranty

Datasheet – Digital Flow Calibrator

Gas Sampling Systems – GSS-1 Tritium, GSS-2 Carbon-14, GSS-3 Sulphur-35


We developed the Gas Sampling System (GSS) has been developed to determine accurate gas activity levels released into the atmosphere.

The bubbler can include a furnace and catalyst to enable both organic and non-organic forms to be collected:

  • Low cost, effective monitoring of gas emissions
  • Low minimum detectable levels
  • Near 99% efficiencies
  • An important factor in the measurement of the aerial discharge is the accurate measurement of both the stack and sample flow rates.
  • The unit is housed in a free standing, lockable enclosure, which provide a secure and clean sampling environment.

Datasheet – Tritium Bubbler   Datasheet – Carbon Bubbler    Datasheet – Sulphur Bubbler