- ACM
- Asbestos-containing material — any material with more than 1% asbestos by weight.
- PACM
- Presumed asbestos-containing material — older suspect material treated as positive until testing proves otherwise.
- Friable
- Material that can be crumbled by hand pressure and therefore releases fibers easily.
- Non-friable
- Asbestos locked in a hard matrix such as floor tile or stucco; hazardous mainly when cut or broken.
- PLM
- Polarized Light Microscopy, the standard laboratory method for identifying asbestos in bulk building samples.
- Point count
- A more precise PLM technique used when asbestos content is near the 1% regulatory threshold.
- Homogeneous area
- A group of material that is uniform in color, texture and installation date — each one needs its own sample.
- Chain of custody
- The signed record tracking a sample from collection to laboratory analysis.
- Chrysotile
- White asbestos, by far the most common type found in California residential materials.
- Amosite
- Brown asbestos, typically found in insulation board and thermal products.
- Encapsulation
- Sealing or covering asbestos material in place instead of removing it — often the cheapest compliant option.
- Abatement
- Licensed removal of asbestos material under containment, performed by a certified abatement contractor.
- NESHAP
- Federal air standard requiring an asbestos survey and notification before most demolition and renovation work.
- BAAQMD
- Bay Area Air Quality Management District, the regional agency enforcing asbestos rules across the nine Bay Area counties.
- SMAQMD
- Sacramento Metropolitan Air Quality Management District, the equivalent agency for the Sacramento region.