You may be familiar with several hazardous materials such as diesel fuel or kerosene that, depending on their formulation, may have a slightly higher flashpoint than more obvious flammable liquids such as gasoline.  However, you may not be aware of the exclusion from full regulation that is allowed for these high-flash materials and how it may be of use to you.

A combustible liquid is defined at 49 CFR 173.120(b)(1) as any liquid that does not meet the definition of any other hazard class and has a flash point of >60˚C (>140˚F) and <93˚C (<200˚F).  A flammable liquid is defined at 49 CFR 173.120(a) as a liquid with a flash point ≤60˚C (≤140˚F), or any liquid in bulk packaging with a flashpoint ≥37.8˚C (≥100˚F) that is intentionally heated and transported above its flashpoint (some exceptions).

There are great advantages to shipping a hazardous material as a combustible liquid instead of as a flammable liquid which will be addressed later.  However, what are you to do if the flashpoint of your hazardous material is ≤60˚C (≤140˚F), thus making it a flammable liquid by definition?  Do you have no choice but to ship it as a flammable liquid?  Not necessarily; there is a regulatory exemption [see 49 CFR 173.150(f)] that allows you to reclassify and ship a flammable liquid as a combustible liquid.  To do so, your flammable liquid must meet the following conditions:

• Doesn’t meet the definition of any other hazard class.
• To be transported within the U.S. only.
• Has a flashpoint of ≥100˚F and ≤140˚F. Click here for an illustration of these temperature ranges.
• To be transported by rail or highway.
• Is not a flammable liquid that is also an elevated temperature material that has been intentionally heated and is transported above its flashpoint.

If you are able reclassify your flammable liquid as a combustible liquid, you must research further to see which of the two following options are available to you.

Option 1:

If the combustible liquid is in a non-bulk package and is not a hazardous waste, hazardous substance, or marine pollutant; then it is not subject to any of the Hazardous Materials Regulations.

Option 2:

If the combustible liquid is in a bulk package or is a hazardous waste, hazardous substance, or marine pollutant; then it is still subject to the following requirements of the HMR:

• Shipping papers.
• Markings.
• Placarding (if in bulk only).
• Incident reporting.
• The general packaging requirements of 49 CFR 173, Subpart B.
• Triennial HazMat Employee training.
• Emergency response information.

The only exceptions allowed in Option 2 then are those for package labeling and security plans, not as good as option 1, but better than nothing.

Perhaps the combustible liquid exemption may be suitable for your operations, perhaps not.  If you are able to reclassify your flammable liquid to a combustible liquid and then use Option 1, you will see a significant reduction in your regulatory requirements and related costs.  In any event, knowing about this exemption and others can provide you with a more complete knowledge of the Hazardous Material Regulations.