Definition
Asbestos floor tiles are resilient floor covering products manufactured with asbestos fibers — most commonly chrysotile (white asbestos) — bonded in vinyl, asphalt, or rubber binding materials. Produced from the 1920s through the mid-1980s, they were installed in millions of residential, commercial, and institutional buildings worldwide. Typical formats are 9×9 inch and 12×12 inch squares in a range of colours and patterns. In intact, undamaged condition, asbestos floor tiles are classified as non-friable: the fibers are firmly bound in the matrix and release is minimal during normal use. However, cutting, sanding, grinding, or breaking the tiles releases respirable fibers. The adhesive (mastic) used to bond them to subfloors frequently contains asbestos as well and may be more friable than the tiles themselves. Before removing, sanding, or installing new flooring over existing resilient tiles in pre-1990 buildings, a bulk sample should be collected and analysed by an accredited laboratory to confirm or exclude asbestos content.
See also:
ACM (Asbestos-Containing Material)
ACM (asbestos-containing material) is any material with more than 1% asbestos by weight. At peak use, ACMs appeared in over 3,000 different products: insulation, fireproofing materials, roofing, flooring, and cement products. Buildings must be surveyed for ACMs before renovation or demolition, and any found must be managed or removed to protect occupants and workers.
Non-Friable Asbestos
Asbestos-containing material that is bonded or encapsulated in a cement, resin, or other binding material, making it difficult to crumble by hand when dry. Examples include asbestos cement sheets, floor tiles, and roofing materials. While considered less hazardous than friable asbestos when undisturbed, it can become friable through weathering, water damage, or mechanical damage.
Chrysotile (White Asbestos)
The most commonly used type of asbestos (CAS 12001-29-5), accounting for approximately 95% of asbestos found in buildings. Chrysotile is a serpentine mineral with curly fibers, also known as white asbestos. While historically considered less dangerous than amphibole asbestos, it is now recognized as carcinogenic and capable of causing mesothelioma and other asbestos-related diseases. Note: chrysotile should not be confused with chrysolite, a synonym for the mineral olivine (a completely different silicate). The similarity has caused persistent errors in print since at least 1909, when mineralogist John W. Evans proposed reviving the original Greek name karystiolite (from καρύστιος λίθος, "Karystian stone"), after the town of Karystos in Euboea, Greece, where fibrous serpentine was quarried in antiquity, the same stone Pliny called marmor carystium.
Asbestos Ceiling Tiles
Asbestos ceiling tiles are acoustic or fire-resistant ceiling panels manufactured with asbestos fibers — typically chrysotile (white) or amosite (brown asbestos) — bonded in mineral wool, cellulose, or calcium silicate matrices. Widely installed in offices, schools, hospitals, shopping centres, and homes from the 1950s through the early 1980s, they were commonly used in drop (suspended) ceiling grid systems. Intact ceiling tiles in good condition are generally non-friable; however, water damage, physical impact, or surface degradation can cause the material to crumble and release fibers. Age and poor condition significantly increase the hazard. Disturbing or removing asbestos ceiling tiles requires prior assessment by a qualified professional; in most countries, confirmed or presumed asbestos ceiling tiles must be removed by a certified or licensed contractor using appropriate containment and PPE.