The Importance of Flash Points in Hazardous Material Storage
For business owners, it’s important to understand the different factors in play when it comes to safely storing hazardous materials. A main criterion with the NFPA and intermediate bulk containers is the flash point of the cargo. Flash point is the lowest temperature at which a liquid can give off enough vapor to form an ignitable mixture in the air. The NFPA clearly states: “NFPA 30 only permits three types of IBCs in an industrial building. Metal, rigid plastic and composite. Only liquids with a closed cup flash point of 38°C (100°F) or greater are permitted to be stored in these containers.”
Knowing this information is critical when determining the appropriate container product and handling methods for the hazmat cargo. It is also important to know there is a distinction being made here between “storage” and “transport”. The NFPA has guidelines that may be enforceable based on the region and that applies to industrial hazmat storage within a building. On the other hand, the UN/DOT maintains guidelines for hazmat transport and these guidelines often differ from those set by the NFPA. Where the NFPA may prohibit a certain hazmat for IBC storage, it may be acceptable for IBC transport per UN/DOT standards.
Definition Flammable and Combustible | Flash Point Examples
The National Fire Protection Agency (NFPA) defines flammable and combustible materials based on their closed cup flash point test result values. According to the NFPA, a Class I flammable material has a flash point less than 100°F; a Class II combustible material has a flash point between 100°F and 140°F; a Class III combustible material has a flashpoint greater than 140°F.
Some examples of flammable liquids and their flash points:
- Acetaldehyde: Flash point around -36°F (-37.8°C)
- Acetone: Flash point around -0°F (-17.8°C)
- Benzene: Flash point around 12°F (-11.1°C)
- Diethyl Ether: Flash point below 73°F (23°C) and boiling point below 100°F (38°C)
- Diesel Fuel: Flash point at 126°F (52°C)
- Ethanol: Flash point at 55°F (13°C)
- Gasoline: Flash point at -49°F (-45°C)
- Hydrochloric Acid: Not flammable, but it can react in a dangerous manner with other products
- Hydrogen Peroxide: Not flammable, but it’s a strong oxidizer and can support combustion
- Isopropyl Alcohol: Flash point at 53°F (12°C)
- Jet fuel (A/A-1): Flash point between 100 – 150°F (37 – 65°C)
- Kerosene (Paraffin): Flash point between 100 – 162°F (37 – 72°C)
- Ligroin: Flash point below 73°F (23°C) and boiling point below 100°F (38°C)
- Methylamine: Flash point at 32°F (0°C)
- Methanol: Flash point at 52°F (11°C)
- Naphtha: Flash point at 43°F (6°C)
- Pentane: Flash point below 73°F (23°C) and boiling point below 100°F (38°C)
- Petroleum Ether: Flash point below 73°F (23°C) and boiling point below 100°F (38°C)
- Sodium Hydroxide: Not flammable, but can generate heat when in contact with water or acids
- Toluene: Flash point at 39°F (4°C)
- Turpentine: Flash point at 95°F (35°C)
- Xylene: Flash point at 80 – 93°F (27 – 34°C)
IBC Material Types for Flammable & Combustible Materials
When handling flammable and combustible cargo, it’s important to choose the appropriate IBC product material type as well as verify that regional framework, standards, and fire codes allow using IBCs for the selected cargo. The National Fire Protection Association (NFPA) has established guidelines that outline when using an intermediate bulk container is suitable, including the common caged IBC tote (composite). These guidelines are primarily outlined in the NFPA 30 code dedicated to flammable and combustible liquids but are also listed in various NFPA flyers and FAQ sheets.
Rigid Nonmetallic IBCs
According to the NFPA, listed rigid nonmetallic intermediate bulk containers are suitable for the onsite storage of Class II and Class III combustible materials only. This includes composite IBCs and all plastic, HDPE IBC containers. Verified, listed IBCs are IBC products that have been tested and certified to meet specific safety standards; this differs from and is in addition to UN/DOT standards. The NFPA states plastic and composite IBCs should never be used for Class I flammable materials.
Metal IBCs
Metal IBCs, including carbon steel and stainless steel, are often used to store and transport flammable and combustible liquids. According to the NFPA, metal IBC containers are suitable for the onsite storage of Class I flammables and Class II / III combustibles. The NFPA recommends during site evaluations, should any Class I hazmat be found stored within a nonmetallic IBC, the hazmat should be transferred to a chemically compatible metal IBC tank.
Summarizing Hazard Classes and IBC Compatibility
Intermediate bulk containers may be suitable for storing and transporting hazardous materials given the flammable/combustible category of the cargo and its selective compatibility with the IBC construction material. According to the United Nations Recommendations on the Transport of Dangerous Goods, HDPE plastic and composite IBCs are suited for Class II and III Combustibles but not Class I Flammables due to the high risk of explosion. Metal IBC containers are suited for Class I, II, and III hazmat given they have approved compatibility and meet any additional handling requirements with the cargo.
- Class I Flammables: Flash point below 100°F (37.7°C). Extremely hazardous. Examples include acetone, ethanol, methanol, naphtha, turpentine.
- Class II Combustibles: Flash point between 100°F and 140°F. Examples include diesel fuel, jet fuel, and kerosene.
- Class III Combustibles: Flash point above 140°F (60°C). Examples include motor oil, vegetable oils, hydraulic and lubricating oils, and ethylene glycol.
Takeaway
Understanding the flash point and chemical properties of a hazardous material is critical for its safe storage and transportation. As it is also important to select the right IBC material type for handling either the categorized flammable or combustible cargo. By following the guidelines set by the NFPA, businesses can ensure compliance and maintain a safe working environment.
Note and Disclaimer: This information is provided for general reference and presented to the best of our knowledge and research, and is not intended as a warranty or claim, either expressed or implied, for the suitability of an IBC for any flammable or combustible classified hazardous material. All such handling involves a certain margin of risk, and all risk is assumed taken, understood, and prepared for by the companies and individuals involved in handling the hazardous material(s). The specifics of NFPA codes and safe practices as well as variances in chemical characteristics is wide and precise. Such business decisions should be made by experienced and knowledgeable professionals who understand the intended cargo and have reviewed the applicable safety guidelines. We recommend reviewing the NFPA 30 code, Chapters 9, 12, and 16 as well as the various fact sheets provided by the National Fire Protection Agency when seeking to store flammable/combustible materials in IBC tote containers. A good starting point for these resources can be found on the NFPA’s website here.