ANFO

Ammonium nitrate prills used in ANFO at a potash mine.
25 kg (55 lb) sacks containing ANFO

ANFO (/ˈænfoʊ/ AN-foh)[1] (or AN/FO, for ammonium nitrate/fuel oil) is a widely used bulk industrial high explosive. It consists of 94% porous prilled ammonium nitrate (NH4NO3) (AN), which acts as the oxidizing agent and absorbent for the fuel, and 6% number 2 fuel oil (FO).[2] The use of ANFO originated in the 1950s.[3]

It has found wide use in coal mining, quarrying, metal ore mining, and civil construction in applications where its low cost and ease of use may outweigh the benefits of other explosives, such as water resistance, oxygen balance, higher detonation velocity, or performance in small-diameter columns. The mining industry accounts for an estimated 90% of the more than 2.5 thousand tonnes (5.5 million pounds) of explosives used annually in the United States.[4] ANFO is also widely used in avalanche hazard mitigation.[5]

  1. ^ "ANFO | explosive". Encyclopedia Britannica. Retrieved 4 May 2019.
  2. ^ Cook, Melvin A. (1974). The Science of Industrial Explosives. IRECO Chemicals. p. 1. ASIN B0000EGDJT.
  3. ^ Encyclopædia Britannica
  4. ^ Edward M. Green (June 2006). "Explosives regulation in the USA" (PDF). Industrial Materials (465): 78. Archived from the original (PDF) on 11 October 2022. Retrieved 3 March 2013.
  5. ^ Cook, Melvin A. (1974). The Science of Industrial Explosives. IRECO Chemicals. p. 2. ASIN B0000EGDJT.