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Diffusion sampling

IVL offers diffusion sampling and analysis of several different substances found in the air. The samplers can measure the incidence of air pollution both indoors and outdoors. IVL's diffusion sampler for nitrogen dioxide (NO2) has been used for measurement all over the world since 1989, and is market leading thanks to its simple design and reliable measuring capacity.

The samplers do not require electricity, which is why they are often called passive samplers, and they normally measure with a time resolution of between a weekend a month. Thanks to their low cost, a larger area can be covered, e.g. a larger number of samplers can be deployed over a large area for a longer period, which gives a good picture of the air pollution concentrations in a city. IVL is accredited in accordance with the International Standard ISO/IEC 17025:2017.  

Examples of applications

  • Mapping of levels in cities
  • Air quality measurement in remote locations
  • Personal sampling
  • Corrosion studies
  • Trend studies over long periods
  • Model validation
  • Infrastructure planning
  • Support in selecting measurement location
  • Epidemiological studies

IVL offers diffusion samplers and analysis of the following substances


Formaldehyde & acetaldehyde


Nitrogen dioxide

Nitrous oxides


Nitric acid

Sulphur dioxide

Hydrogen sulphide

Volatile hydrocarbons (VOCs)­, Outdoor Nordic climate, Outdoor warm climate, Indoor GC-MS

Sulphur dioxide, hydrogen fluoride & hydrochloric acid

Organic acids (acetate, formate)


Q&A - diffusion samplers

Following order confirmation, samples are sent from IVL within two weeks, with the regular postal service. IVL is not liable for delivery delays caused by the postal service.

If the client wants a trackable shipment, this is to be paid for by the client.

Please note that IVL can only provide an estimate of the shipping cost (with DHL), and that this cost can change.

In order for the diffusion sampler to give reliable results, it should be deployed in places where air can freely flow into it from all directions. Thus, for indoor applications, we recommend not placing the sampler in a corner, as this can limit the airflow into the unit. The best location for indoor applications varies from case to case, but we normally recommend that you place the sampler by the ceiling or below a projecting surface (i.e. a shelf), preferably beyond the reach of curious fingers. Remember that the steel mesh must always point downward.

For measurement outdoors, IVL often includes in the shipment an aluminium profile that creates sufficient distance from walls etc., so that air can freely enter the sampler, provided that the profile is installed as per IVL's instructions.

The results that will be reported to you are an average for the measurement period (µg/m³). Consequently, with longer exposure times, it is more difficult to discover any instances of high concentration. For this reason, we normally recommend that our clients conduct a greater number of shorter measurements, instead of fewer and longer ones.

If you want to measure levels in real time, IVL can provide measurement instruments for direct measurement of several different air pollutants.

If you suspect very high levels, you might have to use shorter exposure times, or a sampler that can handle higher levels. If you suspect low levels, you might need a longer exposure time in order to get detectible amounts into the sampler. You can read more about how exposure times affect the samplers' detection limits Pdf, 199.1 kB., and how to calculate exposure times.

For measurement indoors, adhesive pads are always included. The installment devices for personal sampling and for outdoor measurement are shown in the images below.

Personburen uppsättningsanordning
Uppsättning utomhusmätning

Detailed sampling instructions are included with the shipment of samplers.

IVL needs information about whether measurement was conducted inside or outside, because this affects the results.

If you plan to measure in small enclosed spaces, such as a trade fair stand, contact Marta Segura Roux for more information, tel +46 (0) 107886919.

The samplers' shelf life varies, and they must be stored as below, if IVL is to guarantee reliable analysis results. The samplers should normally be sent in immediately after exposure.

Shelf life

  • Samplers for nitrogen dioxide (NO2), sulphur dioxide (SO2), ozone (O3), nitric acid (HNO3), dichlorine (Cl2), ammonia (NH3) and mercury (Hg) should be used within a few months.
  • Volatile hydrocarbons (VOCs) should be used within three weeks of delivery.


  • VOCs – store at room temperature
  • Formaldehyde – should preferably be refrigerated.
  • Other samplers should be stored in a refrigerator. They can be stored at room temperature, but this reduces shelf life somewhat.
  • Samplers must always be stored in the dark.

Once IVL has received your exposed sampler, you can expect the analysis results within six weeks. IVL is not liable for longer response times during holiday periods.

If a client wants a faster service, it is possible to order express analysis, where the analysis report can be received within 10 working days of IVL receiving the samplers. Express analysis costs an additional 50% of the total price for the samplers ordered. If you want express analysis, remember to notify IVL when ordering, because IVL cannot always provide this service, e.g. on short notice.

Ordering diffusion samplers

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