The trace fluid sampling cassette is a sampling device designed for the rapid collection and analysis of a wide range of aerosols in the air. These include fungal spores, pollen, insect parts, fragments of skin cells, fibers and inorganic particles. The air enters the cassette, the particles are affected on the sampling pad, and the air exits through the outlet opening. The airflow and patented cassette housing are designed in such a way that the particles are distributed and deposited straight onto a special glass rail contained in the cassette housing called "track". Benefits: useful for preliminary on-site Mold Testing Paramount, especially if fungal growth is not visible.
Disadvantages of the track trap method:
Fungi cannot be completely specified by this method. For example, Aspergillus sp. and Penicillium sp. They are usually reported together due to similarities in trace morphology.
The viability of the spore cannot be evaluated as it is not possible to distinguish between viable and non-viable
The sampling method is cumbersome and noisy.
Great variation from laboratory to laboratory in identification.
Methodology not accepted by anyone in the industry.
So what happens if the traces cannot distinguish between the species' differences?
Since many of the water penetration forms look the same in a microscope, a trace analysis cannot produce species differentiation. Therefore, a comparison of indoor and outdoor samples will not provide information on the actual differences between samples, only a total number of similar spores. Therefore, if a given inner sample has the same total counts as an external sample, but the species is different, then the inspection is unlikely to detect a moisture problem related to mold. This is because the track tracks assume that the variations of the species are the same from a given set of indoor and outdoor samples. Remember: A number of trams will not identify different species of Aspergillus or Penicillium in a set of indoor and outdoor samples.
Do trams not track tracks in the size range of most water penetration forms?
No. The track trap is a battle collector. The collection efficiency of a track trap depends on the air flow rate and impact physics. In summary, traps do not detect fungal spores less than 3 to 4 microns in diameter. This means that most species of Aspergillus and Penicillium mold are collected in very low amounts in standard track basins compared to larger molds. This phenomenon is a well-known fact but somewhat discussed in the laboratory environment.
So how can we optimize the collection?
To collect virtually all form spores, the assembly method must gather spores of all sizes. Ideally, a filter-type collector should be used where air is collected and sampled through a porous medium. The newly developed systems, which have recently been introduced in the market, make this option practical. In one version, EmTrap, the air sample is withdrawn through a membrane filter with a nominal pore size of 0.8 micron. In contrast to traps, almost all intact traces collected through the filter will be trapped.
So if EmTrap solves the "small track" problem, why should I have to do the more expensive MSQPCR analysis?
Remember that a track number is not the same as identifying a trace species. Whether we count the tracks in a standard track or in a track block, we still can't determine the species as in an MSQPCR. Alternatively, next-generation immunoassays are compatible with the filter collection devices and offer another option for the professional wishing to test the sample on-site.
Okay, but why should I quantify and determine the species for 36 different shapes: Relative Mold Index for EPA and Forms in Group 1 compared to Group 2?
Extensive research done by US EPA UU. It has established the EPA Relative Molding Index, also known by acronym ERMI. The ERMI score reduces the total number of critical mold species to 36 mold species with an internal indicator.
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