TEM CHATFIELD

Similar to New York State's method 198.4, this method is used to determine asbestos content in problematic organically bound bulk samples.

Samples such as floor tiles and roofing materials are not condusive to asbestos analysis.  This is because the asbestos (if present) is usually tightly bound to the matrix material and therefore not easily isolated and detected by microscopy.

These types of materials are classified as Non-friable Organically Bound (NOB).  Some examples of NOB materials include:

• Floor tiles (vinyl and asphalt)
• Roofing Materials
• Mastics
• Caulking

Though the two methods are very similar, EMSL recommends the New York 198.4 method over the Chatfield method as it is a promulgated method.