Asbestos scope, definitions, classes of work and exposure limits practice questions
20 free practice questions from 29 CFR 1926.1101(a) to (d). Each answer is explained and linked to the rule it comes from.
Asbestos scope, definitions, classes of work and exposure limits
20 questions across 8 topics. After each answer you see why it is right, with a link to the official source.
Tip: press A, B, C or D to answer and Enter for the next question. Nothing you answer leaves your browser.
Review all 20 questions
Prefer to read? Here is every question in the Asbestos scope, definitions, classes of work and exposure limits set, grouped by topic. Open a question to see the answer, why it is right and the official source.
Scope and application
1. A crew on a construction site is applying an asbestos-containing asphalt roof coating. What does 1926.1101(a)(8) say about this material?
- A. It is Class II asbestos work
- B. The section does not apply to asbestos-containing asphalt roof coatings
- C. It must be treated as PACM
- D. It is covered only if the coating is friable
Show answer
Answer: B. The section does not apply to asbestos-containing asphalt roof coatings
Paragraph (a)(8) states: "This section does not apply to asbestos-containing asphalt roof coatings, cements and mastics."
Source: eCFR: 29 CFR 1926.1101, Asbestos (as of Nov 4, 2026)
2. Under 1926.1101(a)(7), what is coverage under the asbestos standard based on?
- A. The employer's industry classification code
- B. The number of employees on the site
- C. The dollar value of the construction contract
- D. The nature of the work operation involving asbestos exposure
Show answer
Answer: D. The nature of the work operation involving asbestos exposure
Paragraph (a)(7) states: "Coverage under this standard shall be based on the nature of the work operation involving asbestos exposure."
Source: eCFR: 29 CFR 1926.1101, Asbestos (as of Nov 4, 2026)
ACM, PACM and material categories
3. A product contains chrysotile that was chemically treated during manufacture. Under the 1926.1101(b) definition of asbestos, how is this mineral treated?
- A. It is asbestos, because the definition includes any of the listed minerals that has been chemically treated and/or altered
- B. It is no longer asbestos once chemical treatment has changed it
- C. It is asbestos only while it remains friable
- D. It is asbestos only in buildings constructed no later than 1980
Show answer
Answer: A. It is asbestos, because the definition includes any of the listed minerals that has been chemically treated and/or altered
The definition lists chrysotile and the other minerals and adds "any of these minerals that has been chemically treated and/or altered."
Source: eCFR: 29 CFR 1926.1101, Asbestos (as of Nov 4, 2026)
4. Employees will disturb PACM that has never been sampled. For purposes of 1926.1101, does the term "asbestos" cover this material?
- A. No, it is covered only after a laboratory confirms more than one percent asbestos
- B. Only if the PACM is friable
- C. Yes, because for purposes of the standard "asbestos" includes PACM
- D. No, PACM is covered only by EPA's school asbestos rule
Show answer
Answer: C. Yes, because for purposes of the standard "asbestos" includes PACM
The definition of asbestos ends: "For purposes of this standard, “asbestos” includes PACM, as defined below."
Source: eCFR: 29 CFR 1926.1101, Asbestos (as of Nov 4, 2026)
5. Sprayed-on acoustical plaster in a building constructed in 1972 is PACM under 1926.1101(b). What does the definition say about that designation?
- A. It can never be removed for the life of the building
- B. It may be rebutted pursuant to paragraph (k)(5)
- C. It lapses automatically three years after the building's last inspection
- D. It applies only while the plaster is damaged
Show answer
Answer: B. It may be rebutted pursuant to paragraph (k)(5)
PACM is thermal system insulation and surfacing material in buildings constructed no later than 1980, and "The designation of a material as “PACM” may be rebutted pursuant to paragraph (k)(5) of this section."
Source: eCFR: 29 CFR 1926.1101, Asbestos (as of Nov 4, 2026)
Classes of asbestos work
6. Under the 1926.1101(b) definitions, what separates Class I asbestos work from Class II asbestos work?
- A. Whether the material is friable or nonfriable
- B. The quantity of material removed in one day
- C. Whether the work is done indoors or outdoors
- D. Whether the material removed is thermal system insulation or surfacing material
Show answer
Answer: D. Whether the material removed is thermal system insulation or surfacing material
Class I is "the removal of TSI and surfacing ACM and PACM", while Class II is "the removal of ACM which is not thermal system insulation or surfacing material."
Source: eCFR: 29 CFR 1926.1101, Asbestos (as of Nov 4, 2026)
7. Both Class III and Class IV work can involve maintenance. Under 1926.1101(b), what marks the maintenance and custodial activities that are Class IV work?
- A. Only nonfriable material is present in the work area
- B. The task takes less than one hour
- C. Employees contact but do not disturb ACM or PACM
- D. No PACM is present anywhere in the building
Show answer
Answer: C. Employees contact but do not disturb ACM or PACM
Class IV work "means maintenance and custodial activities during which employees contact but do not disturb ACM or PACM". Class III covers repair and maintenance operations where ACM "is likely to be disturbed."
Source: eCFR: 29 CFR 1926.1101, Asbestos (as of Nov 4, 2026)
8. A crew will remove thermal system insulation in a 1975 building. The insulation is PACM and has never been sampled. How does the 1926.1101(b) definition of Class I work apply?
- A. Class I covers the removal of TSI and surfacing ACM and PACM, so this removal is Class I work
- B. It becomes Class I work only after sampling shows more than one percent asbestos
- C. It is Class II work, because the material is presumed rather than confirmed
- D. It is Class IV work until the material is sampled
Show answer
Answer: A. Class I covers the removal of TSI and surfacing ACM and PACM, so this removal is Class I work
"Class I asbestos work means activities involving the removal of TSI and surfacing ACM and PACM."
Source: eCFR: 29 CFR 1926.1101, Asbestos (as of Nov 4, 2026)
Work terms: disturbance, removal and repair
9. A maintenance task on ACM does not crumble or pulverize it, but it does generate visible debris from the material. Under 1926.1101(b), is this a disturbance?
- A. No, a disturbance requires the matrix to be pulverized
- B. No, unless the debris fills more than one glove bag
- C. Only if the ACM is thermal system insulation
- D. Yes, disturbance includes activities that generate visible debris from ACM or PACM
Show answer
Answer: D. Yes, disturbance includes activities that generate visible debris from ACM or PACM
"Disturbance means activities that disrupt the matrix of ACM or PACM, crumble or pulverize ACM or PACM, or generate visible debris from ACM or PACM."
Source: eCFR: 29 CFR 1926.1101, Asbestos (as of Nov 4, 2026)
10. Under 1926.1101(b), encapsulation of ACM attached to a structure falls within which defined term?
- A. Repair
- B. Removal
- C. Demolition
- D. Aggressive method
Show answer
Answer: A. Repair
Repair means overhauling, rebuilding, reconstructing, or reconditioning of structures or substrates, "including encapsulation or other repair of ACM or PACM attached to structures or substrates."
Source: eCFR: 29 CFR 1926.1101, Asbestos (as of Nov 4, 2026)
Regulated areas, barriers and decontamination
11. Under 1926.1101(b), a regulated area covers the area where Class I, II, and III asbestos work is conducted and what other area?
- A. Every room on the same floor of the building
- B. Any area within 25 feet of the work
- C. Any adjoining area where debris and waste from such asbestos work accumulate
- D. Any area where Class IV work is conducted
Show answer
Answer: C. Any adjoining area where debris and waste from such asbestos work accumulate
A regulated area is "an area established by the employer to demarcate areas where Class I, II, and III asbestos work is conducted, and any adjoining area where debris and waste from such asbestos work accumulate".
Source: eCFR: 29 CFR 1926.1101, Asbestos (as of Nov 4, 2026)
12. A contractor seals plastic over all openings into a work area as a critical barrier. Under 1926.1101(b), what must a critical barrier be sufficient to do?
- A. Keep the work area under negative pressure
- B. Prevent airborne asbestos in a work area from migrating to an adjacent area
- C. Hold all of the waste generated by the job
- D. Trap at least 99.97 percent of particles 0.3 micrometers in diameter
Show answer
Answer: B. Prevent airborne asbestos in a work area from migrating to an adjacent area
"Critical barrier means one or more layers of plastic sealed over all openings into a work area or any other similarly placed physical barrier sufficient to prevent airborne asbestos in a work area from migrating to an adjacent area."
Source: eCFR: 29 CFR 1926.1101, Asbestos (as of Nov 4, 2026)
Competent person and other roles
13. One of the employer's own carpenters wants to step into a regulated area to watch the removal, although nothing in his work duties requires him to be there. Under 1926.1101(b), what makes a person an "authorized person"?
- A. Wearing a respirator while inside the regulated area
- B. Being escorted by a member of the abatement crew
- C. Having passed a respirator fit test
- D. Being authorized by the employer and required by work duties to be present in regulated areas
Show answer
Answer: D. Being authorized by the employer and required by work duties to be present in regulated areas
The definition has two parts: "Authorized person means any person authorized by the employer and required by work duties to be present in regulated areas."
Source: eCFR: 29 CFR 1926.1101, Asbestos (as of Nov 4, 2026)
14. A company leases a building and controls its management and record keeping functions. Which description of "building/facility owner" in 1926.1101(b) fits this company?
- A. The legal entity, including a lessee, which exercises control over management and record keeping functions
- B. Only the holder of the recorded deed to the property
- C. The general contractor on any project in the building
- D. The competent person assigned to the building
Show answer
Answer: A. The legal entity, including a lessee, which exercises control over management and record keeping functions
The rule says "Building/facility owner is the legal entity, including a lessee, which exercises control over management and record keeping functions relating to a building and/or facility" in which activities covered by the standard take place.
Source: eCFR: 29 CFR 1926.1101, Asbestos (as of Nov 4, 2026)
Exposure limits and exposure terms
15. Under 1926.1101(b), when do historic workplace conditions "closely resemble" the conditions of the current workplace?
- A. When the historic job was done by the same employees in the same building
- B. When the major workplace conditions which contributed to the levels of historic asbestos exposure are no more protective than conditions of the current workplace
- C. When the historic workplace conditions were more protective than those of the current workplace
- D. When the historic job took place within the past 30 days
Show answer
Answer: B. When the major workplace conditions which contributed to the levels of historic asbestos exposure are no more protective than conditions of the current workplace
"Closely resemble means that the major workplace conditions which have contributed to the levels of historic asbestos exposure, are no more protective than conditions of the current workplace."
Source: eCFR: 29 CFR 1926.1101, Asbestos (as of Nov 4, 2026)
16. Under 1926.1101(b), what does a negative initial exposure assessment demonstrate?
- A. That no asbestos is present in the building
- B. That one past air sample was below the PELs
- C. That employee exposure during an operation is expected to be consistently below the PELs
- D. That all employees in the area wear respirators
Show answer
Answer: C. That employee exposure during an operation is expected to be consistently below the PELs
It is "a demonstration by the employer, which complies with the criteria in paragraph (f)(2)(iii) of this section, that employee exposure during an operation is expected to be consistently below the PELs."
Source: eCFR: 29 CFR 1926.1101, Asbestos (as of Nov 4, 2026)
Multi-employer worksites
17. On a multi-employer worksite, an enclosure containing Class I work has a significant breach. Under the example in 1926.1101(d)(2), what shall happen?
- A. The building/facility owner shall repair the breach within 24 hours
- B. The general contractor shall repair the breach at the end of the shift
- C. Each employer whose employees are nearby shall repair its share of the breach
- D. The employer responsible for erecting the enclosure shall repair the breach immediately
Show answer
Answer: D. The employer responsible for erecting the enclosure shall repair the breach immediately
Paragraph (d)(2) says hazards "shall be abated by the contractor who created or controls the source of asbestos contamination" and gives the example: "if there is a significant breach of an enclosure containing Class I work, the employer responsible for erecting the enclosure shall repair the breach immediately."
Source: eCFR: 29 CFR 1926.1101, Asbestos (as of Nov 4, 2026)
18. Employees working immediately adjacent to a Class I job are exposed to asbestos because the job's containment is inadequate. Under the example in 1926.1101(d)(3), which is one of the options their employer shall take?
- A. Remove the employees from the area until the enclosure breach is repaired
- B. Have its own employees repair the other contractor's enclosure
- C. Keep working until the next daily check of the enclosure
- D. Leave all action to the primary asbestos contractor
Show answer
Answer: A. Remove the employees from the area until the enclosure breach is repaired
Their employer "shall either remove the employees from the area until the enclosure breach is repaired; or perform an initial exposure assessment pursuant to (f) of this section."
Source: eCFR: 29 CFR 1926.1101, Asbestos (as of Nov 4, 2026)
19. Under 1926.1101(d)(4), what must employers of employees working adjacent to another employer's regulated area take steps on a daily basis to ascertain?
- A. The asbestos content of every material in the regulated area
- B. The integrity of the enclosure and/or the effectiveness of the control method relied on by the primary asbestos contractor
- C. The training records of the primary asbestos contractor's workers
- D. The air monitoring results inside the regulated area
Show answer
Answer: B. The integrity of the enclosure and/or the effectiveness of the control method relied on by the primary asbestos contractor
They "shall take steps on a daily basis to ascertain the integrity of the enclosure and/or the effectiveness of the control method relied on by the primary asbestos contractor to assure that asbestos fibers do not migrate to such adjacent areas."
Source: eCFR: 29 CFR 1926.1101, Asbestos (as of Nov 4, 2026)
20. The general contractor on a project that includes asbestos work is not qualified to serve as the asbestos competent person. Under 1926.1101(d)(5), what shall it do as supervisor of the entire project?
- A. Serve as the competent person for all Class I work
- B. Repair every enclosure breach on the site itself
- C. Ascertain whether the asbestos contractor is in compliance and require it to come into compliance when necessary
- D. Perform all air monitoring for the asbestos contractor
Show answer
Answer: C. Ascertain whether the asbestos contractor is in compliance and require it to come into compliance when necessary
"As supervisor of the entire project, the general contractor shall ascertain whether the asbestos contractor is in compliance with this standard, and shall require such contractor to come into compliance with this standard when necessary."
Source: eCFR: 29 CFR 1926.1101, Asbestos (as of Nov 4, 2026)