TEM ASTM D-6480 (Wipe)

When it comes to asbestos testing, the ASTM D-6480 (Wipe) TEM method stands as a globally recognized standard. Developed by ASTM International, this method employs transmission electron microscopy (TEM) for the analysis of asbestos structure number surface loading.

Why Use ASTM D-6480 (Wipe) TEM?

The primary application of the ASTM D-6480 (Wipe) TEM method is for the broad-spectrum testing of various surfaces for the presence of asbestos. It serves as a valuable tool in assessing a wide range of surfaces within buildings, including but not limited to ceiling tiles, shelving units, electrical components, and duct work. The method offers a quantitative measure of the number of asbestos structures, providing an index of their concentration per unit area sampled.

Methodology and Process

The ASTM D-6480 (Wipe) TEM method outlines a specific procedure for identifying asbestos in samples collected from surfaces. It also provides an estimate of the concentration of asbestos, reported as the number of asbestos structures per unit area of the sampled surface. The method utilizes an indirect sample preparation technique, aiming to disperse aggregated asbestos into its fundamental components - fibrils, fiber bundles, clusters, or matrices.

The sample collection process involves using a particle-free wipe material to collect samples from a potentially asbestos-containing surface. The efficiency of this wipe sampling technique can vary significantly among different substrates, influenced by factors such as surface texture and adhesiveness.

Identifying Asbestos

The identification of asbestos using transmission electron microscopy (TEM) is based on several factors, including morphology, electron diffraction (ED), and energy dispersive X-ray analysis (EDXA). This method enables the determination of the specific types of asbestos fibers present. However, it's important to note that it may not always be able to distinguish between individual fibers of asbestos and non-asbestos analogues of the same amphibole mineral.

Key Considerations

During sample preparation, the dispersion of one or more large asbestos-containing particles may lead to high asbestos surface loading results in the TEM analyses. Therefore, it's recommended to secure multiple independent samples from the same area and analyze at least three such samples using the complete procedure.

It's crucial to understand that the ASTM D-6480 (Wipe) TEM method does not provide procedures or techniques for evaluating the safety or habitability of buildings with asbestos-containing materials. Nor does it ensure compliance with federal, state, or local regulations or statutes. These determinations fall under the user's responsibility.