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Safety guides and audits to make your job as a safety professional easier

Controlling Hazards

Electrical system failures and the misuse of electrical equipment are leading causes of workplace fires.

It's important that fire hazards are identified and controlled in an effective FPP. Employees must be educated on the workplace fire hazards and the procedures to follow to prevent and control fire hazards. They must also learn how to respond to the fires those hazards might cause.

Electrical Hazards

Electrical system failures and the misuse of electrical equipment are leading causes of workplace fires. Fires can result from loose ground connections, wiring with frayed insulation, or overloaded fuses, circuits, motors, or outlets.

To prevent electrical fires, employees should:

  • Make sure that worn wires are replaced.
  • Use only appropriately rated fuses.
  • Never use extension cords as substitutes for wiring improvements.
  • Use only approved extension cords [i.e., those with the Underwriters Laboratory (UL) or Factory Mutual (FM) label].
  • Check wiring in hazardous locations where the risk of fire is especially high.
  • Check electrical equipment to ensure that it is either properly grounded or double insulated.
  • Ensure adequate spacing while performing maintenance.

1. What are the leading causes of workplace fires?

a. Smoking in non-designated areas
b. Electrical system failures and equipment misuse
c. Microwave and other kitchen fires
d. Fires in waste cans and dumpsters

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All portable heaters should be approved by the plan administrator.

Portable Heaters

All portable heaters should be approved by the plan administrator. Portable electric heaters should have tip-over protection that automatically shuts off the unit when it is tipped over.

There should be adequate clearance between the heater and combustible furnishings or other materials at all times.

2. Which of the following is required when using portable heaters in the workplace?

a. Must be certified by the supervisor
b. Manual shut off switch in front and back of unit
c. A thermal index of at least 5 in the on position
d. Adequate clearance between the heater and combustibles

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Office Fire Hazards

Keep storage areas clear of rubbish.

Fire risks are not limited to industrial facilities. Fires in offices have become more likely because of the increased use of electrical equipment, such as computers and fax machines. To prevent office fires, employees should:

  • Avoid overloading circuits with office equipment.
  • Turn off non-essential electrical equipment at the end of each workday.
  • Keep storage areas clear of rubbish.
  • Ensure extension cords are not placed under carpets.
  • Ensure trash and paper set aside for recycling is not allowed to accumulate.

Smoking Policy

In an effective FPP, smoking is prohibited in all company buildings. Certain outdoor areas may also be designated as no smoking areas. The areas in which smoking is prohibited outdoors should be identified by NO SMOKING signs.

3. Fires in offices have become more likely because of _____.

a. use of cell phone causing battery fires
b. higher voltages being used
c. increased use of electrical equipment
d. more employees smoking in the building

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Cutting, Welding, and Open Flame Work

Cutters, welders, and helpers must wear eye protection and protective clothing.

The Plan Administrator and affected employees should ensure the following:

  • All necessary hot work permits have been obtained prior to work beginning.
  • Cutting and welding are done by authorized personnel in designated cutting and welding areas whenever possible.
  • Adequate ventilation is provided.
  • Torches, regulators, pressure-reducing valves, and manifolds are UL listed or FM approved.
  • Oxygen-fuel gas systems are equipped with listed and/or approved backflow valves and pressure-relief devices.
  • Cutters, welders, and helpers are wearing eye protection and protective clothing as appropriate.
  • Cutting or welding is prohibited in sprinklered areas while sprinkler protection is out of service.
  • Cutting or welding is prohibited in areas where explosive atmospheres of gases, vapors, or dusts could develop from residues or accumulations in confined spaces.
  • Cutting or welding is prohibited on metal walls, ceilings, or roofs built of combustible sandwich-type panel construction or having combustible covering.
  • Confined spaces such as tanks are tested to ensure that the atmosphere is not more than ten percent of the lower flammable limit before cutting or welding in or on the tank.
  • Small tanks, piping, or containers that cannot be entered are cleaned, purged, and tested before cutting or welding on them begins.
  • Fire watch has been established.

4. Which of the following situations would prohibit welding and open-flame work?

a. When explosive atmospheres could develop
b. Welding or cutting in sprinklered areas
c. Purging of containers that cannot be entered
d. Cutting or welding on any wall, ceilings or roofs.

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Flammable and Combustible Materials

Keep trash in metal-lined receptacles with tight-fitting covers.

If your workplace contains flammable and combustible materials, the plan administrator should regularly evaluate the presence of those materials.

Certain types of substances can ignite at relatively low temperatures or pose a risk of catastrophic explosion if ignited. Such substances obviously require special care and handling.

Class A Combustibles

These include common combustible materials (wood, paper, cloth, rubber, and plastics) that can act as fuel and are found in non-specialized areas such as offices.

To handle Class A combustibles safely:

  • Dispose of waste daily.
  • Keep trash in metal-lined receptacles with tight-fitting covers (metal wastebaskets that are emptied everyday do not need to be covered).
  • Keep work areas clean and free of fuel paths that could allow a fire to spread.
  • Keep combustibles away from accidental ignition sources, such as hot plates, soldering irons, or other heat- or spark-producing devices.
  • Store paper stock in metal cabinets.
  • Store rags in metal bins with self-closing lids.
  • Do not order excessive amounts of combustibles.
  • Make frequent inspections to anticipate fires before they start.

Water, multi-purpose dry chemical (ABC), and halon 1211 are approved fire extinguishing agents for Class A combustibles.

Check out this short audio clip by Dan Clark of the that tells you the four ways to avoid flashpoint fires and explosions.

5. Class _____ combustibles can act as a fuel and are found in areas such as offices.

a. A
b. B
c. C
d. D

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Flammable and Combustible Materials (Continued)

Class B Combustibles

Water should not be used to extinguish Class B fires caused by flammable liquids.

These include flammable and combustible liquids (oils, greases, tars, oil-based paints, and lacquers), flammable gases, and flammable aerosols.

Handling Class B Combustibles

Click the button to see guidelines for handling Class B Combustibles.

To handle Class B combustibles safely:

  1. Use only approved pumps, taking suction from the top, to dispense liquids from tanks, drums, barrels, or similar containers (or use approved self-closing valves or faucets).
  2. Do not dispense Class B flammable liquids into containers unless the nozzle and container are electrically interconnected by contact or by a bonding wire. Either the tank or container must be grounded.
  3. Store, handle, and use Class B combustibles only in approved locations where vapors are prevented from reaching ignition sources such as heating or electric equipment, open flames, or mechanical or electric sparks.
  4. Do not use a flammable liquid as a cleaning agent inside a building (the only exception is in a closed machine approved for cleaning with flammable liquids).
  5. Do not use, handle, or store Class B combustibles near exits, stairs, or any other areas normally used as exits.
  6. Do not weld, cut, grind, or use unsafe electrical appliances or equipment near Class B combustibles.
  7. Do not generate heat, allow an open flame, or smoke near Class B combustibles.
  8. Know the location of and how to use the nearest portable fire extinguisher rated for Class B fire.

Source: Hazard Communication - Small Entity Compliance Guide.

Water should not be used to extinguish Class B fires caused by flammable liquids. (See Photo) Water can cause the burning liquid to spread, making the fire worse. To extinguish a fire caused by flammable liquids, exclude the air around the burning liquid. The following fire-extinguishing agents are approved for Class B combustibles: carbon dioxide, multi-purpose dry chemical (ABC), halon 1301, and halon 1211.

Class D Combustibles

Locations where combustible metal powders, flakes, shavings, or similarly sized materials are generated at least once every two weeks must install Class D portable fire extinguishers not more then 75 feet from the hazard.

Class K Combustibles

Due to the higher heating rates of vegetable oils in commercial cooking appliances NFPA 10, Portable Fire Extinguishers, now includes a Class K rating for kitchen fires extinguishers which are now required to be installed in all applicable restaurant kitchens. Once a fire starts in a deep fryer, it cannot always be extinguished by traditional range hoods or Class B extinguishers.

6. Which of the following classes of combustibles includes flammable and combustible liquids (oils, greases, tars, oil-based paints, and lacquers), flammable gases, and flammable aerosols?

a. Class A
b. Class B
c. Class C
d. Class D

Check your Work

Read the material in each section to find the correct answer to each quiz question. After answering all the questions, click on the "Check Quiz Answers" button to grade your quiz and see your score. You will receive a message if you forgot to answer one of the questions. After clicking the button, the questions you missed will be listed below. You can correct any missed questions and check your answers again.

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