Sempore Method – Simple Air Sampling
The method works as well on air as liquid. It is now used both for research purposes and for different types of air quality control measurements. Examples of this are quality assurance of supply air in fan controlled ventilation systems and for the determination of particulate pollutants in indoor air in connection with “sick house investigations”.
The filter installations found on most ventilation systems are such that they are able to stop the large particles contained in the air such as, for example, pollen, but the smallest particles pass through them.
- Pollen grains with allergenic particles come into the building.
- Pollen grains are stuck in the filter
- The dangerous particles pass the filter and get into the ventilation system.
The simple air sampling which takes place by means of a filter electrode, the so-called measuring stump, is one of the most important advantages of the Sempore method. Partial pollutants in the air are captured on a patented filter holder provided with a flat membrane, a nucleopore filter, on the upper side.
Particles down to 0.1 μm are concentrated on the filter holder either by air suction through the membrane with a pump or by electrostatic enrichment with the Airpoint air ionizer.
In order to facilitate the practical and safe handling of the filter holders to be sent for analysis, a storage carousel for 10 filters has been designed.
For the air sampling, a pump with a constant airflow of 1,0 l/min is used under 25 min as standard measurement. A typical measurement takes place on several points, usually on four measuring points. By comparing the results with each other and with a sample of the outdoor air as a reference you can localise the source of the problem.
Electrostatic sampling with the air ionizer Airpoint can be used in some situations when sampling needs to be extended for a period of time. In the air ionization, the particles contained in the air are negatively charged and are attracted to the positively charged filter electrode.
The design of the filter electrode saves time during the subsequent analysis work using a scanning electron microscope (SEM) after the gold coating of the membrane. The filter electrodes in their carousel are thus the first part of an integrated rapid diagnostic analysis system.
Through careful examination of the samples via the SEM microscope display, detailed information of the obtained particles is found on the sample, their number, size and shape can be clearly displayed. The screen review determines the final diagnosis and a representative image is chosen for illustration. If necessary, identification of the composition of certain particles can be done by means of EDAX, X-ray analysis.
Scope of applications
The Sempore method can be used to detect mold, bacteria, fiber and dust in the ventilation system or in the room air, which makes the method especially suited as a quality assurance of supply air. It can be used to search for leaks in the ventilation system, damage or soiling of the filter and as a check after duct cleaning.
Mold growth due to moisture damage in the building material can also be revealed. As a quick and easy environmental diagnostic method, it is one valuable aid in the fight against asthma and allergy increase in society. In the field of occupational health and safety, there are many available applications specially in the field where fibers such as asbestos and dust are generated
Sempore sampling and analysis method assures the indoor air quality
- Easy air sampling
- Fast and reliable answers without laboratory cultures
- Control of: Outdoor air; Air supply in ventilation system; Filter function; Air supply ducts in rooms; Room air; Air spaces in walls and floors.