TEM ASTM D-5755 (MicroVac)

The ASTM D-5755 (MicroVac) TEM is a specialized method for asbestos testing. This method employs a micro-vacuuming sampling technique to collect dust off various surfaces. The samples are then analyzed by Transmission Electron Microscopy (TEM) to identify asbestos structures.

Methodology

The MicroVac method is applicable for an estimate of surface loading of asbestos structures starting from approximately 1000 structures per square centimeter. The samples are analyzed based on morphology, Selected Area Electron Diffraction (SAED), and X-Ray Analysis (EDXA).

Significance and Use

This microvacuum sampling and indirect analysis method is used for the general testing of non-airborne dust samples for asbestos. It assists in the evaluation of dust that may be found on surfaces in buildings such as ceiling tiles, shelving, electrical components, duct work, carpet, etc. This test method provides an index of the surface loading of asbestos structures in the dust per unit area analyzed as derived from a quantitative TEM analysis.

Limitations

This test method does not describe procedures or techniques required to evaluate the safety or habitability of buildings with asbestos-containing materials, or compliance with federal, state, or local regulations or statutes.
At present, no relationship has been established between asbestos-containing dust as measured by this test method and potential human exposure to airborne asbestos.

Scope

This test method covers a procedure to (a) identify asbestos in dust and (b) provide an estimate of the surface loading of asbestos in the sampled dust reported as the number of asbestos structures per unit area of sampled surface.

Collection Efficiency

This procedure uses a microvacuuming sampling technique. The collection efficiency of this technique is unknown and will vary among substrates. Properties influencing collection efficiency include surface texture, adhesiveness, electrostatic properties and other factors.

Asbestos Identification