MREs, translation: Meals, Ready (to) Eat seem to be a pretty good idea for disaster conditions and for travelers as well.
But MREs with FRHs, a/k/a Flameless Ration Heaters and known sometimes as FHUs or Flameless Heating Units, are another matter.
The Federal Aviation Administration (FAA) released a report titled "The Fire Safety Hazard of the Use of Flameless Ration Heaters Onboard Commercial Aircraft" includes the following:
"Flameless Ration Heaters (FRH)/Meal, Ready-to-Eat (MRE) are well known to pose certain fire, explosion, and health-related safety issues while in shipment where typically hundreds of these meals are packaged together in a single shipping container. They are also considered to be a hazardous material under the United Nations publication "Recommendations on the Transport of Dangerous Goods" and in that publication are listed as "dangerous when wet." The 2004 Emergency Response Guidebook published by the United States Department of Transportation covers FRHs under guide 138: "Substances—Water-Reactive (Emitting Flammable Gases)" and lists the potential fire and/or explosion hazards. Some of the hazards listed include:
- Produces flammable gases on contact with water
- May ignite on contact with water or moist air
- Some react vigorously or explosively on contact with water
- May be ignited by heat, sparks, or flames
- May reignite after fire is extinguished
"In fact, a major product of the reaction of the salt water and iron-magnesium mixture is hydrogen gas. The release of hydrogen is the primary cause of any fire safety concern surrounding FRHs and has resulted in at least one cargo fire during shipment. In March 2001, a container filled with FRHs was loaded onto a container ship at a naval station in Guam. The ship's crew detected leaking hydrogen from the container and removed it from the ship. Fire fighters decided to attempt to move the contents and spread them among three separate containers. While performing this operation, the contents burst into flames as can be seen in the photo. (Page 1 of report.)
"Tests were performed with individual MREs in an open environment and multiple MREs in a confined space to examine the potential hazard associated with their use in an aircraft cabin. The tests also examined accidental activation of FRHs in a confined area aboard the aircraft, such as in overhead storage bins or a cargo compartment. Temperatures in excess of 215o F and violent ignition events were observed. It is evident from the tests that the release of hydrogen gas from these MREs is of a sufficient quantity to pose a potential hazard onboard a passenger aircraft." (Page 10)
There are a number of companies that make or sell MREs; several make MREs with FRUs, one makes heater-included MREs only for the military, considering the FRUs too dangerous for the civilian market.
By and large, heater-equipped units probably are generally safe if
* the quantity on hand is small
* the storage box is explosion proof and damp proof
Hurricane season prompts many people to head for stores - or the Internet - to stock up on MREs.
But MREs are good for more than hurricane seasons. Think about travel in the winter; you're traveling along in the flivver and you get trapped in a snow storm. Stuck - but if you have an MRE or several, you won't starve. It won't be as tasty as a heated MRE, but, according to Mary Ann of My Own Meals, a/k/a "MOM," it is edible. She should know; MOM staff taste-tests each day's production and, since they don't have time to heat each test meal, they taste them at room temperature.
There is at least one private school in California that requires its students to provide a long-shelf-life meal - MREs meet that requirement - as part of registration. The meal is available in case an earthquake traps the students at the school. Meals are renewed every 5 years. (Do the kids eat the 5-year-old meals? I have no idea.)
Today's MREs remind senior citizens of the old tv dinners. Those, however, had to be heated in an oven. Today's FRU-less MREs can be heated in a microwave or under hot running water. Putting an FRU-equipped MRE into a microwave or under hot water can result in an explosion.
A longer version of this article is available at http://johnglennmbci.com/090720-MREs.html .
John Glenn, MBCI
Enterprise Risk Management/Business Continuity practitioner
Ft. Lauderdale FL
Planner @ JohnGlennMBCI.com