Environmental Monitoring | Diffusion Tubes

Diffusion Tubes / Passive Samplers

Ormantine USA is a major supplier of ready-to-use diffusion tubes with a comprehensive laboratory analysis service. Diffusive (passive) samplers (diffusion tubes) fulfill many of the logistical, analytical and economic requirements of an ideal air monitor. Their simplistic design provides a cost effective, easy to distribute and use sampler, and with the use of various formulations of absorbent, suitable for a wide range of inorganic and organic applications.

Technical Data sheets for all types of tubes and their applications are available on this website. These are backed up by a knowledgeable technical advice department.

Materials Emissions

Odor measurement from printing inks, wood protection, polymers, chemical coatings, varnishes, flooring (plastics/wood), furniture coverings and paints, amongst other items, will become increasingly important with tightening consumer protection legislation. Consumer goods, new office interiors, household furniture, toys etc. that may emit harmful gases can be monitored using equipment from Ormantine.

Paint, Adhesives & Varnish

Assess emissions of VOC from paints and varnishes during manufacture or post applications. Monitor potentially harmful VOCs, even at low levels. We report individual compounds or a sum of total VOCs (TVOC).

Plastic, Wood or Laminate Flooring

Use diffusion tube monitoring as a quality control during the installation of flooring materials, or as long term assessments of hazardous air pollutant emissions from plastic flooring in new or renovated buildings.

New Car Interiors

New vehicle upholstery and linings are manufactured from a high proportion of plastics. Using the VOC diffusion tubes or tedlar bags, monitor and measure the emissions from these materials to assess their impact on the car interior environment.

Indoor Ambient Air Applications

Passive samplers can monitor indoor air, actively or passively, for even low ppb levels of VOCs, ozone, formaldehyde, etc. Periods of monitoring can be set between 1 hour and 4 weeks.

Workplace air quality in offices and new buildings and indoor air surveys of developments on reclaimed land.

New Offices and Living Areas

  • Indoor air tests of emissions of VOCs from paints and varnishes during manufacture or post applications.
  • Innovative extraction and heating systems and sealed buildings may alter air circulation.
  • VOC detectors can identify low levels of potentially harmful or odorous gases

Building on Reclaimed Land

Many new building developments are erected on brownfield/ reclaimed land sites. Passive samplers will provide the means to monitor the internal and external ambient air quality to highlight areas where air toxics are detected, and also monitor the efficiency of remedial actions.

Outdoor Ambient Air Applications


Many industries have the potential to emit gases into the atmosphere. These may be monitored as part of their air pollution control mechanisms. Acid gases such as hydrogen fluoride and hydrogen chloride are common emissions from coal-fired power stations. Phosphates, CFCs, PCBs and PAHs are also emitted from a wide range of industries.

Traffic Management

Vehicular emissions can be monitored spatially or in co-location with auto analyzers. Passive samplers can provide long-term assessments for air modeling, dispersion model validation or determining air management areas. Applications: NO2, NO, SO2, BTEX, O3.

Sewerage/ Landfill

Landfill/ brownfield sites and sewage plants emit odors which can make surrounding areas very unpleasant to live near. Passive sampling offers an inexpensive and simplistic means of monitoring and measurement of odor. Soil contamination with underground VOCs can be monitored using soil probes.


Measuring low concentrations of airborne pesticides are so vital in maintaining a healthy living environment. VOC samplers have a very high sensitivity and can detect very low levels of organo-phosphorous, pesticides and PCBs.

Silage Storage

Ammonia emissions contribute to the ever increasing problem of air pollution in rural areas. Monitor using Palmes diffusion tubes for long-term assessment (2-4 weeks).


By identifying the source of VOCs from chemical and cleaning processes, stack emissions and patterns of airborne concentrations can be traced.


Passive samplers are the ideal tool for carrying out air dispersion modeling and spatial assessments of the effects of SO2, NO2 and VOC air pollution on our forests.


Volatile and semi-volatile organic compounds (VOC and SVOC) can permeate through the soil at a rate dependent on the hydro-geological nature of the strata. Soil probes can be used for soil monitoring.

Landfill Sites

Today’s throw away culture is creating large quantities of waste products which in turn results in wide areas of landfill sites. Some of these sites are eventually remediated for development. Diffusion tubes/ soil probes can be used to trace the migration of VOC/ SVOC in landfill site soil substrates. This method of monitoring can also be used to ensure remedial techniques have been successful.

Contaminated Land Sites

Large areas of our open landscape are surrounded by industrial sites. Spillages of toxic or harmful solvents can occur. VOC diffusion tubes in conjunction with the soil probe can detect and track these spillages with accuracy. In agricultural areas, the use of pesticides can contribute to air pollution and possible health effects. Diffusion tubes will measure the levels of these complex chemicals in the air that we breathe.

Brownfield Sites

With the decline of many heavy industries, large sections of brownfield sites have been created and are subsequently being reclaimed for future development. The ‘cocktail’ of VOCs in these sites can be identified and measured to assist remedial procedures.

Ormantine USA, Ltd. | Environmental Monitoring Division | Peristaltic Pump Tubing Division