Sample collection
This analysis is necessary when the spotting reveals suspicious products or materials for asbestos siding which it is impossible to determine with certainty whether or not they contain asbestos. The product or material must therefore be taken, packaged, identified and click here to sent the analysis laboratory.
Insofar as these are ad hoc verifications, samples are taken without having to develop a sampling strategy. The quantity of samples should allow a macroscopic description of the material. It is generally considered that a few cm3 is sufficient.
This control is governed by the NFX 43050 standard and the COFRAC program 144 .
Receipt of filters and support sheets
The materials to be analyzed asbestos siding must be sent to the laboratory as follows, at a minimum:
Individually packed in double packaging, at least the first of which is waterproof (plastic bags or tubes);
With an indelible identification on the packaging and if possible on the sample itself. The accompanying sheet will include this indication;
Materials adjacent to or associated with the material to be analyzed should be packaged individually and separately as far as possible during on-site sampling, to avoid any errors resulting from mutual contaminations.
In the case of sampling of multilayer materials, the overall analysis or the analysis of the separated layers must be specified on the accompanying sheet.
In the case of specific exposures, and in such a way that it is possible later to interpret any contamination, the sheet must indicate all the information available on the sampling media. Example: flocking sprayed on plaster, on cardboard, etc.
The samples must be sent to the laboratory with an accompanying sheet which will serve as a liaison document between the body responsible for asbestos siding the collection and the laboratory. This sheet must include at least the following elements:
- the identification of the sample indicated on the sample;
- the file or order number;
- identification of the requestor of the analysis;
- the author of the sample (organization, operator);
- the date of collection;
- the date of dispatch;
- the analysis method, either under the responsibility of the laboratory, or envisaged or required by the applicant and to be validated by the analysis laboratory.
In the latter, additional information must be provided:
- the nature of the material (flocking, floor, false ceiling, seal, etc.)
- associated materials
- the visual description of asbestos siding the material in place
- the multilayers identified during sampling and analyzed separately
- Laboratory analysis: counting asbestos fibers
To analyze the presence of asbestos in materials, there are three methods:
- Polarized light optical microscopy (MOLP), according to the MDHS 77 method or any other equivalent method;
- Scanning electron microscopy equipped with an X-ray energy dispersion analyzer (MEBA), according to the VDI method 34.92 or any other equivalent method of asbestos siding;
- As well as transmission electron microscopy equipped with an X-ray energy dispersion analyzer (META), according to standard NFX 43-050 or any other equivalent standard.
- For so-called fibrous layers, the first two methods can be used. For non-fibrous layers, all three can be.
Generally speaking, flocking and heat insulation will be analyzed using the MOLP method. This analysis can be supplemented if necessary by an analysis at the MEBA or the META. False ceilings and other materials will be analyzed according to MOLP methods, possibly supplemented by MEBA or META methods, or according to the META method.