Verisk has compiled guidelines to help underwriters work successfully with insureds to reduce or eliminate hazardous conditions in the use, storage, and maintenance of flammable and combustible liquids.
The misuse of flammable and combustible liquids can cause property losses of catastrophic proportions. Flammable and combustible liquids ignite easily, cause severe fires and explosions, and release toxic fumes. In those scenarios, the potential for loss of life is also very real.
Almost any type of occupancy—anywhere in a facility—may contain flammable and combustible liquids. Those liquids have many different uses, including painting/coating, cleaning, and lubricating, and are excellent solvents. They are also a source of fuel and often serve as raw materials in manufacturing.
The flash point is the lowest temperature at which a liquid gives off enough vapors to form an ignitable mixture with air.
Manufacturers and the National Fire Protection Association (NFPA) use the flash point to ascertain a liquid's flammability. You can use the flash point to determine the volatility of the flammable liquid. For example, gasoline is very volatile, and fuel oil is much more difficult to ignite.
A flammable liquid is a liquid with a flash point below 100oF (38oC). A combustible liquid is a liquid with a flash point at or above 100oF (38oC).
More on identification
While the NFPA 704 system is simple to apply, people who are technically competent and experienced in interpreting the hazard criteria—according to NFPA standards—should perform the hazard evaluation. Often, a qualified individual can determine the ratings in the facility using the data available from the manufacturer supplied Material Safety Data Sheet (MSDS). The MSDS contains information on hazardous materials, including handling procedures and spill response measures. The NFPA 704 standards document describes the technique to perform the ratings.
NFPA 704 doesn't include the actual ratings for specific chemicals. Two other NFPA documents contain hazard property information — NFPA 49, Hazardous Chemicals Data, and NFPA 325, Guide to the Fire Hazard Properties of Flammable Liquids, Gases, and Volatile Solids. The Fire Protection Guide to Hazardous Materials contains all the NFPA documents.
If a rating isn't available in those documents, you can use the NFPA 704 rating system to rate chemicals of interest. Because local conditions have a bearing on the rating, even if your chemical is listed in one of those sources, you may still want to adjust the rating to ensure that conditions don't affect the listed rating.
Propane tank storage with NFPA 704 system identification
During painting/coating processes, flammable and combustible liquids have increased exposure to many ignition sources, such as electrical equipment, heating devices, and hot metal. Underwriters should understand the hazards associated with the following operations.
This process presents serious fire hazards because it involves putting very hot metal parts into a liquid.
Flow coating refers to the application of coating material with nozzles or slotted dispensers. Hazardous conditions may exist if materials are combustible, if heat processes are part of the flow coating, and if surplus materials aren‘t collected properly.
Dip tanks are vats filled with flammable or combustible liquids. Manufacturers use them for dipping a wide range of items, such as furniture, tools, and various materials used in manufacturing processes. The tanks must have overflow and fire protection.
Spray booths are power ventilated structures that enclose spray operations. Many manufacturers and repair facilities use spray booths. Fires involving liquids and residues from spray operations ignite easily, spread rapidly, and are difficult to extinguish.
Safe spray operations
Unsafe spray operations
Underwriter's checklist for flammable and combustible liquids
- Are storage tanks constructed, supported, and protected properly?
- Are storage cabinets properly constructed — given the type of liquid stored in them?
- Can the storage cabinet adequately accommodate the amount of liquid stored in it?
- Does the storage area clearly identify that flammable and combustible liquids are present?
- Will storage containers protect the liquid from ignition?
- Do personnel follow proper procedures when they fill containers or when liquids are present?
- Is the area around flammable and combustible liquids free of anything that could cause ignition?
- During painting/coating processes, are flammable and combustible liquids exposed to ignition sources?
- If spray applications are used, is there a standard spray booth or room?
- Is the spray booth or room cleaned regularly?
- Has the facility installed a fire protection system?
- Do personnel inspect and maintain the fire protection system regularly?