Review and Evaluation of Trioxane

Fuel, Compressed, Trioxane, Ration Heating M MIL-F-10805D

Trioxane is a solid fuel that has been in use by the US Military for the last few decades to heat individual rations in the field. It has also come into widespread civilian use within the United States by campers, hikers and hunters.

Image of 15 and 30 gram bars of trioxane with packaging.

As with all solid chemical fuels, Trioxane is most useful for heating water or food but it is not terribly practical for any cooking which requires temperature control. It's main benefits are that it is compact and easier to carry than gas cylinders or liquid fuels. Compared to chemical fuels such as Esbit or Hexamine, Trioxane is relatively inexpensive.

Trioxane can be purchased from most camping and military surplus stores as well as through mail order. You should shop around as the price can vary significantly.

It is generally packaged in a cardboard box with three bars per box. Each bar comes wrapped in a plastic lined foil envelope. As long as the envelope remains sealed, trioxane will last for many years, however when the material is exposed to air it will evaporate and crumble over a period of weeks.

There are two sizes of bars that have been manufactured. The first is the 30 gram bar which is scored to break into 3 pieces of about 10 grams each. It is marked with NSN number 9110-00-263-9865. The second newer version contains an unscored 15 gram bar. It is marked with NSN number 9110-00-889-3553.

NSN Weight Net Weight
per bar gms Per Box gms
9110-00-889-3553 15 45
9110-00-263-9865 30 90

Cautions

The fuel itself is toxic and should not be used in an enclosed area and care should be taken that food is not contaminated with it. Avoid handling the bars by hand and if you do, you should wash your hands afterward. Once ignited trioxane melts as it burns. It is impractical to extinguish the fuel and save for later.

How to Use Trioxane Effectively

Trioxane ignites easily and is relatively clean burning but it will smoke and produce soot if too much is used at one time. The best practice is to light only 10 to 20 grams at a time and then light more when the first piece burns out. It generally takes about 30 grams of Trioxane to heat 8 to 12 ounces of water or food although on a hot day you may be able to get away with using only 15 grams. The container should be 1 to 2 inches above the burning fuel. A 15 gram bar will take about 3.5 to 4.0 minutes to burn completely which means that if you are heating food you must stir it frequently to prevent scorching on bottom of the pot.

Trioxane Performance Tests

The following test was conducted on January 26, 2007 to evaluate the amount trioxane needed to heat varying quantities of water during cold weather conditions. The outside air temperature was 31.9 degrees Fahrenheit with very light wind . All temperature readings were done with a digital thermometer which was calibrated with boiling water. Elevation was 400 feet above sea level. No more than 15 to 20 grams of trioxane was burning at any one time. Trioxane was not added until the previous piece had been almost completely consumed.

Image of small esbit stove with bar of trioxane fuel U.S. Military canteen cup and tea kettle used in this evaluation.

The stove used was a small german military Esbit stove with the following dimensions 4 x 3 x 0.9 inches.

Air Temp 31.9 ºF GRAMS OF WATER BURN TIME
Canteen Cup with 8 oz of water TRIOXANE TEMPERATURE ºF MINUTES
Starting Water Temp 55 ºF 10 119.0 ºF 3.5
15 122.0 ºF 3.5
30 173.0 ºF 7.0
Canteen Cup with 16 oz of water
Starting Water Temp 55 ºF 15 95.0 ºF 3.5
30 131.5 ºF 7.0
45 157.0 ºF 10.5
Tea Kettle with 8 oz of water
Starting Water Temp 54 ºF 15 127 ºF 3.5
Tea Kettle with 16 oz of water
Starting Water Temp 54 ºF 30 143 ºF 7.0
45 176 ºF 10.0
Tea Kettle with 24 oz of water
Starting Water Temp 54 ºF 20 100.0 ºF 5.5
40 148 ºF 10.5
60 194 ºF 15.0

The following test was conducted on February 5, 2007 to evaluate the amount trioxane needed to heat 16 ounces of water to a rolling boil during cold weather conditions and moderate winds. The outside air temperature was 14.9 degrees Fareheit. 16 ounces of boiling water is the amount required for many freeze dried meals

Air Temp 14.9 ºF GRAMS OF WATER BURN TIME
Windy TRIOXANE TEMPERATURE ºF MINUTES
Tea Kettle with 16 oz of water
Starting Water Temp 60 ºF 75 212 ºF Rolling Boil 18

The following comparison was done on February 8, 2007 to find out the amount of Esbit or Trioxane fuel needed to heat 16 ounces of water to boiling.

Air Temp 29.0 ºF GRAMS OF WATER BURN TIME
Tea Kettle with 16 oz of water Starting Water Temp 65 ºF Fuel TEMPERATURE ºF MINUTES
Trioxane 45 212 ºF 11.5
Esbit 21 212 ºF 14.5

Trioxane fuel contains a small amount methylene blue and stearin in addition to the chemical, trioxane.