Definitions here are general, plain-language explanations to help you follow a conversation with a certified professional. Regulatory definitions in Colorado rules can be more precise, and where it matters, the wording in CDPHE's regulation and guidance controls. If a term in your paperwork is unclear, ask the person who wrote it to explain it in writing.
Terms from the inspection report
- ACM
- Asbestos-containing material. A material that lab analysis has shown to contain asbestos above the applicable threshold.
- PACM
- Presumed asbestos-containing material. A material treated as positive without sampling, often because sampling was impractical or would damage it.
- Homogeneous area
- A group of material that is uniform in color, texture and apparent age, sampled as one unit.
- Friable
- Able to be crumbled, pulverized or reduced to powder by hand pressure when dry.
- Non-friable
- Bound tightly enough that hand pressure will not crumble it, such as intact floor tile or cement siding. It can become friable when broken or ground.
- PLM
- Polarized light microscopy, a common lab method for analyzing bulk building material samples.
- Trigger levels
- Quantity thresholds in Colorado rules above which permits, notifications or other requirements apply. Ask a certified professional which apply to your job.
Terms from the abatement proposal and job site
- Containment
- The sealed work area, usually built with plastic sheeting over walls, floors and openings.
- Negative air
- Keeping containment at lower air pressure than surrounding spaces, using machines with HEPA filters, so air leaks inward rather than outward.
- HEPA
- High-efficiency particulate air filtration, used in air machines and vacuums on abatement jobs.
- Decontamination unit
- A series of chambers where workers remove protective clothing and clean up before leaving containment.
- Wet methods
- Keeping material wet during removal to reduce the release of fibers.
- Glovebag
- A sealed plastic bag with built-in gloves used for small removals, typically on pipe insulation.
- Encapsulant
- A liquid sealant that binds or coats material, used in encapsulation or to lock down residual fibers after removal.
- Clearance
- Visual inspection and air sampling after cleanup that determine whether the area can be reopened.
- Waste shipment record
- The document that tracks asbestos waste from the site to the receiving facility.
- Critical barrier
- Sheeting sealed over doors, vents and other openings so air and debris cannot pass between the work area and the rest of the building.
- Lockdown
- A coating sprayed on surfaces after removal and cleaning to bind any remaining fibers before containment comes down.
- Project designer
- A certified role for planning larger abatement projects; ask whether your job calls for one.
General information for the Denver area, not a quote or professional advice. In an emergency, call 911.