What is Asbestos?
Asbestos is an umbrella term for certain silicate minerals that are made up of bundles of fibers, which in turn are made up of very long and thin fibers that can separate from each other. Asbestos is a mineral product with high tensile strength, high flexibility, resistance to chemical and thermal attack, electrical insulation, and spinnability.
Because the fiber of asbestos is soft, it has the characteristics of insulation, heat insulation, sound insulation, high temperature resistance, acid and alkali resistance, corrosion resistance and wear resistance, etc., and is widely used in construction, electrical appliances, automobiles, household goods, etc.
Asbestos hazards
As early as 1987, the World Health Organization classified asbestos as a Group 1 carcinogen. The biggest harm of asbestos to the human body is that it will release extremely fine, indistinguishable asbestos fibers with the naked eye, which are difficult to be processed and discharged after entering the human body, and often accumulate in the body to cause damage to the human body, the most common are asbestosis, lung cancer, pleural mesothelioma, peritoneal mesothelioma and gastrointestinal cancer and other fatal diseases.
Asbestos detection technology
Polarizing light microscopy (PLM) method.
Polarizing microscopy is one of the most widely used and highly accurate testing techniques. Each mineral has its own specific optical characteristics under polarizing microscopy, such as color, pleochroism, extinction type, ductile symbol, and dispersion staining. The accuracy of the test results is greatly improved by the simultaneous control of multiple optical forms.
X-ray diffraction (XRD) method.
The XRD method is based on the fact that each mineral crystal has its specific diffraction parameters, and the test data is compared with its diffraction parameters to characterize each mineral crystal. However, XRD can only test the crystal parameters of the mineral, but cannot determine the actual form of the mineral.
Scanning electron microscopy-energy spectroscopy (SEM-EDS) method.
The SEM-EDS method characterizes the type of asbestos by combining its microscopic morphology with its elemental characteristics. The SEM-EDS method can give the morphological characteristics and element distribution of asbestos at the same time, and the two types of information are combined with each other to support each other, which greatly improves the accuracy of the results.
Asbestos testing standards.
GB T 23263-2009 Method for determination of asbestos content in products.
ISO 22262-1-2012 Bulk Materials-Part 1: Sampling and Qualitative Determination of Asbestos in Commercial Bulk Materials.
NIOSH 9000-2015 X-ray diffraction (XRD) determination of asbestos.
AS 4964-2004 Methods for the Qualitative Identification of Asbestos in Bulk Samples.
sn/t 2649.2-2010 Determination of Asbestos in Imported and Exported Cosmetics.
Safety and Technical Specifications for Cosmetics (2015 Edition).