Worker Safety and Health During Fire Cleanup

Workers face hazards even after fires have been extinguished. Employers performing cleanup and other work in areas damaged or destroyed by fire are required to identify and evaluate these hazards, correct any unsafe or unhealthful conditions and provide training and instruction to employees (California Code of Regulations, Title 8, sections 1509, 1511, 1518 and 3203).

Fire and Fire Byproducts

Fire can continue to be a hazard during cleanup of a fire-damaged area. Heat sources from smoldering wood or other debris can come into contact with flammable material and could ignite and cause fire again. Employers should therefore provide fire extinguishers at every cleanup job. Fire extinguishers are required to be provided when employees are working inside buildings or structures or on construction or demolition sites (sections 1922 and 6151).

In addition, toxic, flammable, or asphyxiating gases or vapors from fires may persist in enclosed spaces and under debris. See guidance on Respiratory Protection During Fire Cleanup Operations.


After an outage, electrical deaths and injuries can occur as power lines are reenergized and electrical equipment is turned on.

  • Employers must allow only qualified electrical workers, as defined in section 2700, to work on or near downed power lines and restore electrical power.
  • Employers must allow only qualified line clearance tree trimmers, as defined in section 2700, to conduct tree trimming operations in the vicinity of energized power lines (sections 2950–2951).
  • Other workers must not be allowed to perform any function in proximity to energized high-voltage lines (section 2946).
  • Overhead electrical power lines must be considered energized until the utility company verifies that the lines are not energized, and the lines are visibly grounded at the work site (section 2946).

If water is or has been near electrical circuits or electrical equipment, employers must ensure that the following precautions are taken:

  • Turn off power at the main breaker or fuse of the service panel for the building.
  • Do not turn power on or use electrical equipment until electrical circuits and equipment are inspected by a qualified person, as defined in section 2300 and section 2700.
  • Do not use electrical equipment or circuits that have been exposed to heat from fire until inspected by a qualified person, as defined in section 2300 and section 2700.
  • Unless all electrical power is off, never enter flooded areas or areas with standing water.
  • Do not touch electrical equipment if wet or if the ground or surface is wet.

If generators are used at the worksite, employers must ensure they comply with the following safety requirements:

  • Generators should be properly grounded (except for portable and vehicle-mounted generators under certain circumstances, provided certain other safety measures are taken) (sections 2395.1-2395.114; exceptions and alternative safety measures are provided in section 2395.6).
  • 120-volt, alternating current, single-phase, 15-ampere and 20-ampere receptacle outlets on construction sites that are not a part of the permanent wiring of the building or structure must have approved ground-fault circuit interrupters to protect employees (section 2405.4, subsection (c)). Otherwise, the employer must implement an assured equipment grounding conductor program (section 2405.4, subsection (d)).
  • No electrical power source, including a generator, is allowed to be connected to a premises’ wiring system, or parts of such a system, unless positive means are used to prevent the transmission of electricity beyond the premises’ wiring system or beyond any intentionally segregated parts of the wiring system. Steps to ensure that electricity is not transmitted beyond the premises wiring system would include switching the main power breaker or fuse to the "off" position, however this may not be sufficient in all cases (section 2320.9).
    • Once switched off, employers should consider locking out or tagging out the main power breaker or fuse to ensure that they are not inadvertently turned on (section 2320.4).
    • Employers should contact the utility provider before connecting a generator to a premises’ wiring system.
  • See additional information from PG&E on generator safety:

(See sections 2320.1–2320.10, 2340.1, 2380.1 and 2485.2)

Flammable Gases

Employers must ensure that pipes and tanks containing flammable gases, if potentially damaged or leaking, are properly shut off (subsection (c) of section 3329 and subsection (a) of section 5416). See additional information from the Pacific Gas and Electric Company (PG&E).

Unstable Structures

Never assume that fire-damaged structures or buildings are stable. They may be structurally damaged or weakened and can collapse without warning. Employers must ensure that precautions, such as the following, are taken:

  • Do not allow work to be performed in or around any fire-damaged structure until it has been examined and certified that it is safe for work by a registered engineer or other qualified person.
  • Assume that all stairs, elevated floors, and roofs are unsafe until inspected.
  • Establish procedures and provide training to ensure that employees leave the structure immediately if it shifts, or if there are unusual noises or other signs of impending collapse.

(Sections 3203 and 3241).

Note: Even after a building or structure is determined to be safe, employees working in or around these structures may be exposed to falling objects. Employers must therefore provide and ensure that employees wear hardhats or helmets, safety glasses, gloves and adequate foot protection such as steel-toed shoes (sections 3380–3385).


During demolition or dismantling of damaged buildings, structures, and equipment, there is an increased risk of hazards such as unexpected collapse, falling objects, damaging utilities and exposure to hazardous materials. Before commencing work, employers should review all demolition safety requirements in sections 1733 –1737. Requirements include the following:

  • A qualified person must conduct a written survey of the structure to determine the condition of the structural components and the possibility of an unplanned collapse of any portion of the structure and adjacent structures (section 1734).
  • Employers must determine if any type of hazardous chemicals, gases, explosives, flammable materials, or similarly dangerous substances have been used in any pipes, tanks, or other equipment on the property. These hazards must be eliminated before demolition is started (section 1735).
  • Demolition work must be under the immediate supervision of a qualified person with the authority to secure maximum safety for employees (section 1734).
  • Utility companies must be notified and all utility services shut off or otherwise controlled before starting demolition, unless electricity or water is needed for demolition. In those cases, the utility services must be relocated or rearranged as necessary and protected from physical damage (section 1735).

Sharp or Flying Objects

Employees handling, cutting or breaking up debris may be exposed to sharp objects, flying objects and other cutting hazards. Employers must therefore provide and ensure that employees wear appropriate eye, hand and foot protection (sections 3380, 3382, 3384 and 3385). See guidance on Personal Protective Equipment During Fire Cleanup Operations.


Digging with an excavator or other equipment presents the risk of striking and damaging underground installations such as natural gas, electric, sewer, and communication lines. Damage to underground installations may cause fire, explosion, electric shock, or release of toxic materials.

Employees entering an excavation may be injured or killed due to cave-ins, falling materials, or falling equipment.

Identifying underground installations before excavating

  • Before starting excavation work, the approximate locations of all underground installations that may be encountered during excavation operations must be determined (section 1541 and Government Code section 4216.4).
  • An excavator planning to conduct excavation work must notify the following entities of the excavator's intent to dig at least two working days before starting an excavation: (1) the appropriate regional notification center and (2) all known owners of underground installations in the area who are not members of a notification center.
    • Before notifying the appropriate regional notification center, the excavation areas must be marked as specified in Government Code section 4216.2 (section 1541).
    • For northern California, the regional notification center is Underground Service Alert North 811. Website: Phone: 811
    • For southern California, the regional notification center is Underground Service Alert of Southern California. Website: Phone: 811
  • After notifying the regional notification center and prior to beginning excavation work, the excavator must receive positive responses from all known owners/operators of underground installations confirming the locations of underground installations or confirming the owner/operator does not operate an underground installation that would be affected by the proposed excavation (section 1541).
  • After the approximate locations of underground installations are determined and excavation work begins, the exact location of underground installations must be determined by safe and acceptable means (such as digging with hand tools), when approaching the approximate location of an underground installation (section 1541 and Government Code section 4216.4).
  • All employees exposed to excavation hazards during excavation work must be trained in the notification requirements and excavation practices provided in section 1541 and Government Code sections 4216 through 4216.9 (section 1541).
  • Any damage to underground installations discovered or caused during excavation work must be reported to the facility owner/operator or regional notification center (section 1541).

Protecting employees entering excavations

  • A permit from Cal/OSHA must be obtained before the construction of excavations 5 feet or deeper into which any person is required to descend (section 341).
  • Adequate protective systems must be used to protect employees entering excavations 5 feet or greater in depth, and where a potential for cave-in exists (section 1541.1).
  • A stairway, ladder, ramp or other safe means of egress must be provided for excavations that are 4 feet or more in depth (section 1541).
  • Employees must not be allowed to work in excavations where there is accumulated water, unless adequate precautions have been taken to protect employees (section 1541).
  • Support systems must be installed to ensure the stability of structures adjacent to or adjoined to excavations (section 1541).
  • Adequate protection must be used to protect employees from loose rock or soil that could fall or roll from an excavation face (section 1541).
  • Materials and equipment must be kept at least 2 feet from the edge of excavations, or retaining devices must be used to keep materials from falling into excavations, or a combination of both if necessary (section 1541).
  • Inspections of excavations, the adjacent areas, and protective systems shall be done by a competent person daily and as needed during each shift for indications of possible cave-ins, failure of protective systems, hazardous atmospheres, or other hazardous conditions (section 1541).

See Article 6 of the Construction Safety Orders for a complete listing of title 8 requirements for excavation activities.

Tree Work

Tree work includes trimming, pruning, felling, and removal of trees and bushes. Tree workers climb trees, use portable ladders, work at heights while using hand and portable power tools, work near energized overhead or downed power lines, feed chippers, and perform other hazardous operations. Employers engaged in tree work during wildfire cleanup should ensure it is done safely and in compliance with Cal/OSHA’s tree work regulations.

Review Cal/OSHA’s Tree Work Safety web page for more information on ensuring tree work safety, such as developing a comprehensive health and safety program that includes written safety rules and safe work procedures for all tasks performed by tree workers, and providing proper protective equipment and training.

Haulage Vehicles

Haulage vehicles used during wildfire cleanup present hazards to pedestrians, nearby workers, and operators if not used or maintained properly. Employers should ensure that all machinery and equipment used for haulage are:

  • Designed to safely sustain all reasonably anticipated loads,
  • Used in accordance with the manufacturer’s recommendations, and
  • Inspected daily and maintained as recommended by the manufacturer.

Haulage vehicle and earthmoving equipment operations must comply with Cal/OSHA’s haulage and earthmoving regulations in general industry, haulage and earthmoving regulations in construction, and machinery and equipment regulations.

Carbon Monoxide Poisoning

Gasoline or diesel-powered pumps, generators and pressure washers may be used during cleanup. When in use, these machines generate carbon monoxide gas, which is colorless, odorless, tasteless and potentially lethal. It is nearly impossible to tell whether ventilation is sufficient to prevent excessive carbon monoxide buildup (section 5155) without using personal carbon monoxide monitors. Therefore, in most situations, employers must not use gasoline or diesel-powered equipment indoors (sections 3662, 5141 and 5146).

Ash, Soot and Dust

Ash, soot and dust disturbed during cleanup may be inhaled and cause irritation or damage to workers’ lungs. Employers must therefore take the following precautions:

  • Use feasible engineering controls to ventilate and provide filtered air to indoor work areas (section 5141).
  • Use a high-efficiency particulate air (HEPA) vacuum when cleaning ash, soot and dust (section 5141).
  • When exposures to airborne ash, soot and dust cannot be controlled within the limits provided in section 5155 (for carbon black, polycyclic aromatic hydrocarbons and particulates) or the exposures would probably cause injury or illness (sections 5140 and 5141), employers must provide and ensure that employees use properly fitted, NIOSH-certified air-purifying respirators designated as N-95 or greater (section 5144).
    • When an employer is required under Cal/OSHA regulations to provide employees with respirators or the employer requires employees to use respirators, the employer must have a written respiratory program that includes the elements listed in section 5144, subsection (c)(1).
    • When respirator use is not required by Cal/OSHA regulations or by the employer, employers may provide respirators at the request of employees or allow employees to use their own respirators if the employer determines that such respirator use will not in itself create a hazard. The employer must provide the respirator users with the information contained in Appendix D to section 5144 and must follow all other requirements in section 5144, subsection (c)(2).
    • See additional guidance on respiratory protection during fire cleanup operations and using N-95 (or greater) respirators.


Insulation, flooring, roofing materials, appliances, and furnishings in fire-damaged structures may contain asbestos, which can damage the lungs and cause cancer. Since asbestos does not burn, it becomes concentrated in the ash and debris when the rest of the structure burns. Asbestos related work is regulated under section 1529 and section 5208. The requirements are discussed on Cal/OSHA's Asbestos Information page

Hazardous Liquids

Fires in commercial and residential buildings and water used to fight fires can damage or dislodge tanks, drums, pipes and equipment that may contain hazardous liquids. Any cleanup of hazardous spills must be performed only by employees who have the required skills, knowledge and training (subsection (q) of section 5192). Employers must provide these employees with the necessary personal protective equipment and emergency equipment to perform the work (subsection (q) of section 5192). Other employers must ensure that damaged or dislodged equipment containing hazardous liquids is not moved or altered without first obtaining instruction from the local fire department.

Other Hazardous Substances

Residential and commercial structures are composed of materials that may release or break down into hazardous substances when burned. These materials include synthetics (such as plastics), petroleum products (such as asphalt shingles), treated wood, adhesives, and metals. Residences and business may also contain items that are composed of hazardous substances or that become hazardous when burned, such as electronics, appliances, batteries, vehicles, household chemicals, pesticides and herbicides. After a fire, the remaining ash, debris, and underlying soil will be contaminated with the hazardous substances. The dangers may not be obvious, because contaminated ash, debris, and underlying soil may look the same as uncontaminated material.

Some of the specific hazardous substances of concern include:

  • Arsenic is a known human carcinogen and can cause nausea and vomiting, abnormal heart rhythm, blood vessel damage, nerve damage, and skin redness and swelling.
  • Cadmium is a known human carcinogen and may also damage the lungs and weaken bones.
  • Lead damages almost every organ and system in the body, particularly the brain and kidneys. Exposure to lead can also cause miscarriages and high blood pressure.
  • Manganese can damage the nervous system and cause changes in behavior and slow, clumsy movements.
  • Nickel can cause skin rashes. Breathing high concentrations of nickel dust may cause lung damage and cancer of the lung and nasal sinus.
  • Zinc may cause skin irritation from direct contact.
  • Polycyclic aromatic hydrocarbons (PAHs) may be carcinogenic, can inhibit the body’s ability to fight infection, and can cause skin redness and inflammation.
  • Polychlorinated biphenyls (PCBs) may be carcinogenic and can cause liver damage, acne, and skin rashes.
  • Polybrominated biphenyls (PBBs) may be carcinogenic and can cause acne and skin rashes.
  • Dioxins and furans can cause skin rashes, liver problems, and elevated blood fats.

Dust generated from ash, debris, and underlying soil disturbed during cleanup operations may contain the hazardous substances listed above. Airborne exposures will vary from day to day and from job to job. Potentially toxic dust must be controlled by thoroughly wetting the debris, ash, and soil before and during removal. Respirators should also be used during fire cleanup work.

In addition to breathing contaminated dust, workers may be exposed to hazardous substances when it gets on their skin. While some hazardous substances can be absorbed through the skin, any can be ingested unknowingly if workers do not wash their hands and face before eating, drinking, or smoking. Employers are required to provide washing facilities with soap and water and make them accessible to all employees (section 1527 and section 3366).

If employees are working in potentially contaminated areas, the employer must train employees on the hazards and must provide and ensure that employees use the correct respirators, gloves and other personal protective equipment (sections 3380–3385, 5144, and 5194). See guidance on Respiratory Protection During Fire Cleanup Operations and Personal Protective Equipment During Fire Cleanup Operations.

Heat Illness

For employees working outdoors, employers must provide potable drinking water, appropriate rest breaks and access to shade to prevent heat illness (section 3395). More detail is available on Cal/OSHA’s Heat Illness Prevention page.

Confined Spaces

A confined space is a space that has limited means for entry and exit and is not designed for continuous employee occupancy. Examples include manholes, crawl spaces, pits, tanks and silos. Employees working in confined spaces can face life-threatening hazards such as toxic exposures, asphyxiation, electrocutions and unguarded moving machinery. Employers need to evaluate worksites to determine if there are confined spaces, and take precautions to ensure that employees who may enter confined spaces are protected. Such precautions include, but are not limited to:

  • Procedures to identify confined spaces that may contain serious hazards
  • Procedures to ensure unauthorized persons do not enter these spaces
  • Development of a written confined space program if employees need to enter these spaces
  • Establishment of an entry permit system
  • Identification and evaluation of all potential hazards that may exist before entering a space, as well as those that may develop because of work activities
  • A plan to eliminate or control all identified hazards
  • Continuous monitoring of atmospheric hazards
  • Training program for all workers who will enter a confined space or serve as an attendant to protect authorized entrants
  • Development of an emergency and rescue plan with training and equipment in case an unforeseen situation occurs

(Sections 1950-1962 and 5156-5158)

Additional Information

Fire Cleanup Hazards and Safety Precautions

Wildfire Cleanup Training Tools in English and Spanish

Protecting Workers Exposed to Smoke from Wildfires

September 2021