Class II Asbestos Work: Exposure Limits, Controls, and Notices

OSHA’s requirements for Class II asbestos work are set out in 29 CFR 1926.1101 and cover every step from identifying the material through disposing of the waste. Class II applies to the removal of asbestos-containing materials other than thermal system insulation and surfacing material — think floor tiles, roofing, siding, wallboard, and ceiling tiles. The rules require trained workers led by a certified competent person, wet removal methods with HEPA-filtered vacuums, containment or a documented negative exposure assessment, respirators unless specific conditions are met, and labeled leak-tight waste handling, all to keep airborne fibers below the permissible limits.

What Class II Covers

The federal standard sorts construction-related asbestos activities into four classes based on the material. Class II is the removal of any asbestos-containing material that is not thermal system insulation or surfacing material. In practice that means floor tiles and sheet flooring, vinyl and asphalt flooring mastic, roofing felt and shingles, cementitious siding, transite panels, wallboard, and ceiling tiles.¹ These materials bind fibers in a matrix, so they release less than pipe insulation or sprayed-on fireproofing. That lower baseline risk is why Class II has its own controls rather than the full Class I containment.

Identification comes first. OSHA requires that asphalt and vinyl flooring installed in 1980 or earlier be presumed to contain asbestos unless the employer affirmatively determines otherwise through laboratory analysis or another method that meets the standard.² The same presumption applies to thermal system insulation and surfacing material in buildings constructed by that date. Treating pre-1980 flooring as asbestos-free without testing is a fast path to a citation.

The Two Exposure Limits

Every control in the standard exists to keep workers below two airborne fiber thresholds. The time-weighted average permissible exposure limit is 0.1 fiber per cubic centimeter of air over an eight-hour shift. The excursion limit is 1.0 fiber per cubic centimeter averaged over any 30-minute sampling period.³

The Negative Exposure Assessment

A negative exposure assessment is the employer’s documented demonstration that a specific job will keep fiber levels below both limits. Three methods qualify: objective data showing the material cannot release fibers above the limits under worst-case conditions, monitoring data from a comparable job within the prior 12 months, or initial breathing-zone samples from the current job.⁴

Whether an employer has a valid negative exposure assessment changes what else is required. Without one, indoor Class II jobs need critical barriers over every opening, respirators become mandatory, daily air monitoring is required, and the employer must set up a full decontamination area. With one, the employer can skip the critical barriers, may be able to forgo respirators under certain conditions, and is exempt from daily monitoring.

Training, Competent Person, and Medical Exams

Workers removing common Class II materials — roofing, flooring, siding, ceiling tiles, transite panels — need at least eight hours of training that includes hands-on practice, covering the specific work practices and engineering controls for the material category involved.⁴ For Class II work involving materials outside those common categories, training must still cover the relevant work practices but carries no fixed minimum hours. Training happens before the first assignment and repeats at least annually.

Every job site also needs a designated competent person. For Class II work this individual must complete a supervisor course meeting the EPA Model Accreditation Plan: 40 hours over five days, at least 14 hours hands-on, individual respirator fit-testing, and a written exam.⁵ The competent person can identify hazards on the spot and take immediate corrective action, including stopping work.

Medical surveillance is required for any employee who performs Class I, II, or III asbestos work for a combined total of 30 or more days per year, or who is exposed at or above the permissible exposure limit regardless of how many days worked.⁶ The 30-day trigger counts all asbestos work combined across a year, not just days on a single project.

Notifications Before Work Begins

Two notification systems apply: OSHA notices to other workers and building occupants, and EPA notices for larger jobs.

OSHA Notices to Other Employers and Occupants

Building owners must notify prospective employers, their own employees, other employers on multi-employer sites, and tenants about the presence, location, and quantity of asbestos-containing materials before work begins. The notice must be written or communicated personally. The removal employer has a parallel duty: before starting, they must inform the owner, their own employees, and employers of workers in adjacent areas about the asbestos location, quantity, and precautions being taken.⁷

After completion, the removal employer must inform the owner and neighboring employers within 10 days about the current location and quantity of any remaining asbestos and any final monitoring results. If any employer on the site discovers previously unknown asbestos-containing material, they must notify the owner and all other on-site employers within 24 hours.

EPA NESHAP 10-Day Notice

The EPA’s National Emission Standard for Asbestos requires a separate written notification at least 10 working days before stripping or removal begins on projects involving 260 or more linear feet of material on pipes, 160 or more square feet on other components, or 35 or more cubic feet where length or area cannot be measured.⁸ Demolition projects require the 10-day notification regardless of the quantity of asbestos present. Large flooring or roofing jobs routinely clear the 160-square-foot threshold, so this notice is easy to overlook and carries its own penalties.

Engineering Controls and Work Practices

The baseline is wet methods and HEPA filtration. Physical containment gets added based on conditions.

Wet Methods

All asbestos-containing material must be kept wet during handling, cutting, removal, and cleanup. A fine mist of water or amended water reduces the ability of fibers to become airborne when the material breaks or is pried loose.² The one exception is roofing work on sloped surfaces where wetting would create a fall hazard, and even there the employer needs a negative exposure assessment and must remove the material intact.

HEPA Vacuums and Drop Cloths

HEPA-filtered vacuums capture dust generated during removal. The filters must trap at least 99.97 percent of particles 0.3 micrometers in diameter.⁹ Impermeable drop cloths go beneath all removal activity. Together these two controls form the minimum for any Class II job.

Indoor Containment

For indoor Class II work without a negative exposure assessment, or where the material will not be removed substantially intact, critical barriers must cover all openings to the regulated area, including windows, doors, and ventilation intakes. An alternative isolation method is allowed if perimeter air monitoring verifies it prevents fiber migration.² HVAC systems serving the regulated area must be shut down or sealed off. With a valid negative exposure assessment and intact removal, these containment steps are not required.

Respirators

Respirators are mandatory for Class II work under any of these conditions: material is not removed substantially intact, wet methods are not used, no negative exposure assessment exists, or air monitoring shows levels above the TWA or excursion limit.⁷ Anyone entering a regulated area where respirators are required must also wear one.

Material-Specific Rules

Beyond the general controls, the standard prescribes extra practices for specific materials. Most Class II violations happen here, because workers default to general demolition methods the standard specifically prohibits.

Roofing

Asbestos-containing roofing must be removed intact to the greatest extent feasible. When that is not possible, wet methods are required unless wetting creates a safety hazard. Cutting machines used on roofing must be continuously misted, and when a power roof cutter is used on built-up roofs with asbestos-containing felt, all dust from the cut must be collected by a HEPA dust collector or vacuumed along the cut line.⁴ Removed material cannot be thrown or dropped to the ground. It must be carried down by hand or lowered through a covered dust-tight chute, crane, or hoist. Any non-intact material still on the roof at the end of a shift must be bagged, wrapped in plastic, or kept wet. Roof-level air intake vents must be isolated or the ventilation system shut down.

Flooring

Vinyl and asphalt flooring removal has strict prohibitions. Sanding is not permitted. Mechanical chipping is prohibited unless it occurs inside a negative-pressure enclosure meeting Class I containment specifications.² More broadly, cutting, abrading, or breaking any Class II material is prohibited unless the employer can show that less aggressive methods are not feasible. Floor tiles should be pried up intact and kept wet throughout.

Siding, Shingles, and Transite Panels

Cementitious siding, shingles, and transite panels are designed to be removed in intact units: shingles unscrewed or unclipped, transite sheets unbolted rather than broken apart. The general Class II prohibition against cutting or breaking applies with particular force, because cementitious materials release fibers readily once fractured.

When Class II Work Must Escalate to Class I

The line between Class II and Class I is about material type, not about what happens during the job. But when material crumbles instead of coming off intact, or when aggressive methods become necessary, the employer must step up to Class I-level controls. Mechanical chipping of flooring requires a negative-pressure enclosure built to Class I specifications.² The standard also explicitly allows any Class II work to be performed using Class I methods, and employers sometimes choose this voluntarily where intact removal is unlikely. Glove bags and glove boxes, Class I tools, can be used on Class II material as long as they fully enclose it.

Plan for intact removal, but have a contingency plan that includes Class I controls in case the material starts breaking apart. Discovering mid-job that you need a negative-pressure enclosure and don’t have one means shutting down the work area entirely.

Regulated Area and Decontamination

A regulated area must be established around all Class II work. Only authorized, properly equipped personnel may enter.

When exposures exceed the permissible limits, or when no negative exposure assessment exists, the employer must set up an equipment decontamination area adjacent to the regulated area. This area needs an impermeable drop cloth on the floor, sized large enough for workers to clean equipment and remove protective equipment without spreading contamination. Work clothing must be HEPA-vacuumed before removal, and all equipment and container surfaces must be cleaned before leaving. Workers enter and exit the regulated area exclusively through this space.⁴ With a negative exposure assessment, these formal decontamination requirements do not apply, though standard hygiene practices still should be followed.

Cleanup, Waste, and Shipment Records

After removal, all surfaces in the work area must be cleaned using HEPA vacuums and wet wiping. Visible dust or residue on any surface, including the plastic sheeting itself, must be removed before the containment is taken down. All waste — removed material, used drop cloths, disposable protective clothing, HEPA vacuum bags — goes into leak-tight containers while still wet. Bags must be six-mil plastic double-bagged, or thicker than six mil if single-bagged.²

Warning Labels

Every bag or container of asbestos waste must carry a label reading: DANGER / CONTAINS ASBESTOS FIBERS / MAY CAUSE CANCER / CAUSES DAMAGE TO LUNGS / DO NOT BREATHE DUST / AVOID CREATING DUST. Signs posted in the work area can substitute for individual container labels if they carry the same information.

Transport and Disposal

Asbestos waste must go to a landfill permitted to accept it. Under EPA rules, a waste shipment record must accompany every load transported off-site. The record must include the generator’s name and contact information, the disposal site’s name and location, the quantity of waste in cubic yards, the transporter’s identity, and the date of transport.¹⁰ The generator must also certify that the shipment is properly classified, packed, and labeled for highway transport. If a signed copy of the record does not come back from the disposal site within 35 days, the generator must follow up with the transporter or facility. If it still has not arrived by day 45, a written report goes to the responsible EPA or state agency. Records must be retained for at least two years.

Recordkeeping Retention

Retention periods vary by document type. Training records — worker name, training provider, course dates, and curriculum — must be maintained and made available for inspection. Medical surveillance records must be kept for the duration of each worker’s employment plus 30 years.¹¹ That “plus 30 years” language catches employers off guard: a worker who spent a decade with the company generates records that must be stored for 40 years total. Air monitoring data, exposure assessments, and the objective data underlying any negative exposure assessment should all be preserved as part of the compliance file. Asbestos-related diseases can take decades to appear, and cutting these retention periods short creates real liability when a former worker develops symptoms years later.

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eCFR. 29 CFR 1926.1101 – Asbestos – Section: Definitions
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eCFR. 29 CFR 1926.1101 – Asbestos – Section: Methods of Compliance
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eCFR. 29 CFR 1926.1101 – Asbestos – Section: Permissible Exposure Limits
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Occupational Safety and Health Administration. 29 CFR 1926.1101 – Asbestos
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eCFR. Appendix C to Subpart E of Part 763 – Asbestos Model Accreditation Plan
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Occupational Safety and Health Administration. Standard Interpretations – Asbestos Medical Surveillance Requirements for Class III Work Performed Less Than 30 Days Per Year
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eCFR. 29 CFR 1926.1101 – Asbestos
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eCFR. National Emission Standard for Asbestos
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eCFR. 29 CFR 1926.1101 – Asbestos – Section: Definitions
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eCFR. 40 CFR 61.149 – Standard for Waste Disposal for Asbestos
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eCFR. 29 CFR 1926.1101 – Asbestos