7.5 Hazard Communication, Asbestos, Lead, and Silica: Managing Unknown Materials

Hazard Communication, Asbestos, Lead, and Silica: Managing Unknown Materials

Quick Answer: Hazardous-materials compliance on a roof is a program, not a reaction. The base layer is Title 8 CCR § 5194, the Hazard Communication Standard: a written program, labeled containers, a safety data sheet (SDS) readily accessible for every hazardous substance on site, and training before first assignment. On top of that sit three substance-specific standards a roofer meets constantly: asbestos (§ 1529), lead (§ 1532.1), and respirable crystalline silica (§ 1532.3). The rule for anything you cannot identify is simple and testable: stop, presume it is hazardous, and sample it.

The Law and Business blueprint lists hazardous/unknown materials as one of three Safety sub-topics. The word unknown is doing real work there — the exam tests whether a contractor knows what to do with a material of uncertain composition, not just whether they can recite an exposure limit.

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1. The Hazard Communication Program (Title 8 CCR § 5194)

Section 5194 is California's adoption of the Globally Harmonized System. Every roofing contractor that brings adhesives, primers, solvents, sealants, coatings, foam chemicals, or fuel onto a job site is covered.

The five required components:

1. Written program — identifies who maintains it, how SDSs are obtained and kept, how containers are labeled, how employees are trained, and how contractors on multi-employer sites are informed.
2. Chemical inventory — a list of the hazardous substances known to be present, keyed to the SDS file.
3. Labels — every container must carry the product identifier, signal word ("Danger" or "Warning"), hazard statements, pictograms, precautionary statements, and supplier information. Secondary containers — the pail a worker decants primer into — must be labeled too.
4. Safety Data Sheets — the 16-section GHS format, kept readily accessible to employees on each shift and in the work area. A binder locked in a truck ten miles away is not accessible.
5. Training — before first assignment and whenever a new hazard is introduced; covers the standard's requirements, the operations where hazardous substances are present, how to detect a release, the physical and health hazards, protective measures, and how to read labels and SDSs.

California adds Proposition 65 on top of federal-style HazCom: warnings are required for listed chemicals that cause cancer or reproductive toxicity, and roofing touches several — crystalline silica, coal tar pitch volatiles, and lead among them.

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2. Asbestos (Title 8 CCR § 1529)

The Presumption Rule

This is the provision that decides most roofing cases. In buildings constructed before 1981, thermal system insulation and surfacing material are presumed to be asbestos-containing material (PACM) unless the presumption is rebutted by sampling performed by a qualified person. Asphalt and vinyl flooring installed before 1981 is likewise presumed.

Roofing materials that historically contained asbestos include asbestos-cement (transite) shingles and panels, built-up roofing felts and base sheets, flashing cements and mastics, and aluminized asphalt coatings. A contractor tearing off a roof on a pre-1981 building who has not tested is not operating on a hunch — they are operating against a regulatory presumption.

Class Structure and Contractor Registration

Cal/OSHA sorts asbestos work into Classes I through IV. Removal of asbestos-containing roofing that is not thermal system insulation or surfacing material is generally Class II work. Every class requires a trained competent person, a regulated area, wet methods, HEPA local exhaust on any powered cutting, prohibition on dry sweeping and compressed air, and intact removal wherever feasible.

Two separate authorizations are commonly tested and commonly confused:

Exposure limits: 0.1 fiber per cubic centimeter as an 8-hour time-weighted average, with a 30-minute excursion limit of 1.0 f/cc.

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3. Lead (Title 8 CCR § 1532.1)

Lead reaches roofers through pre-1978 painted fascia, barge rafters, eaves and soffits, and through solid sheet-lead vent jacks and soldered valley and gutter work.

• Permissible Exposure Limit: 50 micrograms per cubic meter of air as an 8-hour TWA
• Action Level: 30 µg/m³, which triggers exposure monitoring and medical surveillance obligations
• Presumed-exposure trigger tasks: manual demolition, manual scraping and sanding, power tool use without ventilation, and torch burning or welding on lead-coated surfaces all require interim protection — respirators, protective clothing, change areas, hand-washing, training, and initial monitoring — until monitoring proves exposures are below the PEL
• Prohibited: open-flame burning or torching of lead-coated surfaces, dry sweeping, and compressed-air cleaning

Where a roofing job disturbs painted surfaces on a pre-1978 residence or child-occupied facility, the federal EPA Renovation, Repair and Painting rule and the California Department of Public Health lead-related construction certification requirements may apply in addition to § 1532.1.

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4. Respirable Crystalline Silica (Title 8 CCR § 1532.3)

Silica reaches roofers whenever concrete or clay tile, masonry, or fiber-cement is cut, drilled, or ground — and tile cutting is a daily roofing operation.

• Permissible Exposure Limit: 50 µg/m³ as an 8-hour TWA
• Action Level: 25 µg/m³ as an 8-hour TWA
• Two compliance routes:
  1. Table 1 specified exposure control methods. For each listed task the employer implements the specified engineering control, work practice, and respiratory protection — for a handheld power saw, that is an integrated water delivery system that continuously feeds water to the blade, plus the specified respirator when used indoors or for more than four hours outdoors. Follow Table 1 fully and no exposure assessment is required for that task.
  2. Alternative exposure control methods. Perform an exposure assessment, then control to the PEL with engineering and work-practice controls, supplemented by respirators.
• Also required: a written exposure control plan naming a competent person, restricted access where exposures exceed the PEL, a prohibition on dry sweeping and compressed air where feasible alternatives exist, medical surveillance for employees required to wear a respirator for 30 or more days a year, and training.

Wet-cutting tile is not a courtesy to the neighbors. It is the Table 1 engineering control, and dry-cutting tile on a roof without it is a citable violation.

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5. The Unknown Material Protocol

A crew opens a 1960s low-slope roof and finds a grey fibrous board under the membrane that nobody recognizes. The compliant sequence:

1. Stop work on that material. Do not cut it, break it, sweep it, or throw it down a chute.
2. Isolate. Keep other trades and the public out of the area; do not let debris migrate.
3. Presume it is hazardous. On a pre-1981 building the presumption is built into § 1529; even after 1981, an unidentified material is treated as hazardous until proven otherwise.
4. Sample it using a qualified person — a Cal/OSHA-certified asbestos consultant or site surveillance technician for ACM, a certified lead inspector or risk assessor for lead — with analysis by an accredited laboratory.
5. Notify. Tell the owner in writing. Under B&P Code § 7159.6 the added scope requires a written change order signed by both parties before the extra work begins on a residential project — a discovered hazard does not authorize a contractor to proceed and bill.
6. Re-scope. If the result is positive and the work exceeds the thresholds, the removal may require a C-22 asbestos abatement contractor, Cal/OSHA registration, and air district notification before anyone touches it again.
7. Document. Sampling results, notifications, change order, disposal manifests, and worker training all go in the project file.

The contractor who guesses here carries the entire liability: Cal/OSHA citations, air district penalties, the cost of a full decontamination, and the personal injury exposure of every worker on the roof that day.