CIRUS (Canada India Reactor Utility Services)[1][2][3] was a research reactor at the Bhabha Atomic Research Center (BARC) in Trombay near Mumbai, India. CIRUS was supplied by Canada in 1954, but used heavy water (deuterium oxide) supplied by the United States. It was the second nuclear reactor to be built in India.

It was modeled on the Canadian Chalk River National Research X-perimental (NRX) reactor.[4] The 40 MW reactor used natural uranium fuel, while using heavy water as a moderator.[5] It is a tank reactor type with a core size of 3.14 m (H) × 2.67 m (D). It first went critical July 10, 1960.[5]

The reactor was not under IAEA safeguards (which did not exist when the reactor was sold), although Canada stipulated, and the U.S. supply contract for the heavy water explicitly specified, that it only be used for peaceful purposes. Nonetheless, CIRUS produced some of India's initial weapons-grade plutonium stockpile,[6] as well as the plutonium for India's 1974 Pokhran-I (Codename Smiling Buddha) nuclear test, the country's first nuclear test.[7] At a capacity factor of 50–80%, CIRUS can produce 6.6–10.5 kg of plutonium a year.

CIRUS was shut down in September 1997 for refurbishment and was scheduled to resume operation in 2003. The reactor was brought back into operation two years late in 2005. During refurbishing, a low-temperature vacuum evaporation-based desalination unit was also coupled to the reactor to serve as demonstration of using waste heat from a research reactor for sea desalination. Even if the reactor has a life of twenty more years, India had declared that this reactor would be shut down by 2010 in accordance with the Indo-US nuclear accord reached between Indian Prime Minister Manmohan Singh and US President George W. Bush.[7] The reactor was shut down on 31 December 2010.[8]


  1. ^ "50-Yr Old Research N-Reactor CIRUS Shut Down". Outlook.
  2. ^ "Research N-reactor CIRUS to shutdown permanently on December 31". DNA. 18 December 2010.
  3. ^ Evans, Brian L. (2013). The Remarkable Chester Ronning: Proud Son of China. University of Alberta. p. 189. ISBN 9780888646637. Canada India Reactor Utility Services.
  4. ^ "Canadian-Indian Reactor, U.S." NTI. Archived from the original on 17 February 2016. Retrieved 10 November 2012.
  5. ^ a b "Cirus reactor". Bhabha Atomic Research Center. Archived from the original on 9 July 2007. Retrieved 2007-04-09.
  6. ^ Exporting Disaster ~ The Cost of Selling CANDU Reactors (3). Retrieved on 2013-12-06.
  7. ^ a b Gopal, Neena (2006-07-03). "PM to announce Cirus reactor shutdown". Gulfnews. Archived from the original on 19 October 2008. Retrieved 2007-04-09.
  8. ^ "Research N-reactor CIRUS to shutdown [sic] permanently on December 31". DNAIndia. 2010-12-18.

Coordinates: 19°00′28″N 72°55′07″E / 19.00778°N 72.91861°E / 19.00778; 72.91861