Preventing the loss of life and property

Working safely with hazardous materials

By Vicki Bell

February 27, 2003

The cost of industrial fires can be enormous in terms of fatalities, serious injuries, property loss, revenue loss, and the costs of replacing equipment and repairing or rebuilding facilities.

Not surprising, companies that insure manufacturing companies report that fire is the leading cause of property loss. Terry Stevens, assistant vice president, Casualty Underwriting Division of CNA Insurance, Chicago, a company that provides Fabricators & Manufacturers Association-endorsed programs to metal fabrication companies, said, "Damage by fire is the largest cause of property loss in our FMA book of business. We suspect that the cause of those fires is not dissimilar to the industry averages.

"Of our largest FMA property losses over the past three years, damage by electrical shorts caused by improper wiring and outdated electrical systems have caused the most significant dollar amount of damage."

Combine faulty electrical systems; careless use of welding, cutting, and other spark-generating equipment; and the presence of flammable or combustible substances and you have a disaster waiting to happen.

The Ohio Bureau of Workers' Compensation's Division of Safety and Hygiene recently reported that more than 21 percent of industrial fires are the result of flammable or combustible liquid ignition. Proper storage and use of these substances are critical. So critical that many groups have developed strict codes, standards, and regulations regarding storage and use. A search for information on flammable liquids on the Occupational Safety and Health Administration's (OSHA) and the National Institute for Occupational Safety and Health's (NIOSH) Web sites yields data for hundreds of substances.

Safety Checklist

Besides giving detailed information on specific substances, OSHA also provides a general checklist for dealing with these types of substances safely. The following questions are among the checklist items:

• Is proper storage practiced to minimize the risk of fire, including spontaneous combustion?
• Are approved containers and tanks used for the storage and handling of flammable and combustible liquids?
• Are all connections on drums and combustible liquid piping, vapor, and liquid tight?
• Are all flammable liquids kept in closed containers when not in use?
• Are bulk drums of flammable liquids grounded and bonded to containers during dispensing?
• Do storage rooms for flammable and combustible liquids have explosion proof lights?
• Do storage rooms for flammable and combustible liquids have mechanical or gravity ventilation?
• Are all solvent wastes and flammable liquids kept in fire-resistant, covered containers until they are removed from the work site?
• Are firm separators placed between containers of combustibles or flammables, when stacked one upon another, to ensure their support and stability?
• Are fuel gas cylinders and oxygen cylinders separated by distance, and fire-resistant barriers, while in storage?
• Are safety cans used for dispensing flammable or combustible liquids at a point of use?
• Are all spills of flammable or combustible liquids cleaned up promptly?
• Is vacuuming used whenever possible rather than blowing or sweeping combustible dust?
• Are storage tanks adequately vented to prevent the development of excessive vacuum or pressure as a result of filling, emptying, or atmosphere temperature changes?
• Are storage tanks equipped with emergency venting that will relieve excessive internal pressure caused by fire exposure?
• Are "NO SMOKING" rules enforced in areas involving storage and use of hazardous materials?
• Are appropriate fire extinguishers mounted within 75 feet of outside areas containing flammable liquids, and within 10 feet of any inside storage area for such materials?
• Are extinguishers free from obstructions or blockage?
• Are all extinguishers serviced, maintained, and tagged at intervals not to exceed one year?
• Are all extinguishers fully charged and in their designated places?

The ABCs of Fire Extinguishers

Portable fire extinguishers deploy an extinguishing agent that will either cool burning fuel, displace or remove oxygen, or stop the chemical reaction so a fire cannot continue to burn. When the handle of an extinguisher is compressed, it opens an inner canister of high-pressure gas that forces the extinguishing agent from the main cylinder through a siphon tube and out the nozzle, much like a can of hair spray.

Different types of fire extinguishers are designed to fight different types of fire. The three most common types of fire extinguishers are air-pressured water extinguishers, CO₂ extinguishers, and dry chemical extinguishers.

All portable fire extinguishers must be approved by a nationally recognized testing laboratory such as Underwriters Laboratories Inc. (UL) or Factory Mutual Research (FM) to verify compliance with applicable OSHA standards 1910.157(c)(2).

Equipment that passes the laboratory's tests are labeled and given an alphanumeric classification based on the type and size of fire it will extinguish. The classification code will contain the letter A, B, C, or a combination of those letters, depending on the type of fire the unit will extinguish: A- for ordinary combustibles requiring a water-type extinguisher; B-CO₂ for flammable liquids; C-dry chemical for electrical fires; A, B, and C-multipurpose dry chemical for all three kinds of fires. Combustible metals such as magnesium and sodium require special extinguishers, labeled D.

An overview of portable fire extinguishers that includes instructions for reading the label to determine coverage area can be found athttp://www.osha.gov/SLTC/etools/evacuation/portable_about.html.

Hazardous substances must be handled carefully. Fabricators that use them must follow the storage and handling guidelines and train employees in the proper use of the substances and safety measures. They also must routinely verify that procedures are being followed and that all equipment, including fire extinguishers, are in proper working order.