Wipe Sampling

Wipe sampling collects settled dust by wiping a measured area of a surface with a moistened wipe, which is then sent to a laboratory and examined for asbestos, usually by electron microscope. It shows whether a surface is contaminated and is a common companion to microvacuum sampling.

Origin

Wipe sampling has long been used in industrial hygiene to test surfaces for lead and other contaminants. It was adapted for asbestos in building and abatement work, and ASTM published a standard wipe method for asbestos, ASTM D6480, in the late 1990s.

Significance in Asbestos Context

A wipe collects dust that a vacuum nozzle may leave behind on smooth surfaces, so investigators sometimes use it on desks, ledges, vehicle interiors, lockers and equipment. Like microvacuum sampling, it is evidence that asbestos was present and had spread, which can support take-home, bystander and building claims. It is also used after abatement to check that surfaces were cleaned. Its limits are similar too: results depend on how firmly and how far the sampler wiped, there is no regulatory standard for asbestos on surfaces, and a surface count cannot be converted directly into what a person breathed. Experts usually present wipe results alongside air samples, product testing and witness testimony rather than on their own.

Example Sentence

Wipe samples from the inside of the family car's trunk, where the work bag had been kept for years, showed amosite fibers.

Related Terms

Settled Dust, ASTM D6480, Microvacuum Sampling, Transmission Electron Microscopy (TEM), Take-home Exposure, Clearance Air Testing

Notes

• Wipe testing is usually done by an accredited inspector; home test kits may not hold up as evidence.
• Ask for the laboratory report itself, not just a summary, and keep it with your records.
• Tell your lawyer about places that have not been cleaned or renovated since the exposure, such as attics, garages or old vehicles.