A report recounting a litany of near-misses in which nuclear weapons came close to being launched by mistake concludes that the risk of potentially catastrophic accidents is higher than previously thought and appears to be rising.

Too Close for Comfort: Cases of Near Nuclear Use and Options for Policy, published on April 29 by Chatham House, the international think-tank based in London, says that “individual decision-making, often in disobedience of protocol and political guidance, has on several occasions saved the day,” preventing the launch of nuclear warheads.

The report lists 13 instances since 1962 when nuclear weapons were nearly used. In several cases the large-scale launch of nuclear weapons was nearly triggered by technical malfunctions or breakdowns in communication causing false alarms, in both the U.S. and Russia. Disaster was averted only by cool-headed individuals gambling that the alert was caused by a glitch and not an actual attack.

The Chatham House authors say the risks appear to be rising. Nuclear weapons are spreading — most recently to North Korea — and disarmament is stalling. Russia and the U.S. still have an estimated 1,800 warheads on high alert, ready to launch between five and 15 minutes after receiving the launch order — a fact that becomes all the more significant with rising tensions over Ukraine.

“The question today is: are these risks worth it?” said Patricia Lewis, Chatham House research director for international security and one of the report’s authors. “You can imagine a situation in which tensions rise and signals come in and people misinterpret what is going on. Will people always have sound enough minds to take the time to make a reasoned decision?”

The mental state of some of the leaders who had their fingers on the nuclear button has sometimes been a source of worry. Richard Nixon and Boris Yeltsin both raised concerns among their top advisers with their heavy drinking. In May 1981 the newly elected French President, Francois Mitterand, left the French nuclear launch codes at home in the pocket of his suit. President Jimmy Carter did the same in the 1970s, and the suit as well as the codes were taken to the dry cleaners. The U.S. launch codes went missing again when Ronald Reagan was shot on March 30, 1981. FBI agents had them, along with the injured President’s bloodied trousers.

The report focusses on cases in which nuclear weapons came close to being launched deliberately on the basis of bad or incomplete information.

However, there is an additional risk of accidents inherent in the maintenance of stockpiles of more than 17,000 warheads held by Russia, the U.S. and the other seven nuclear-armed states. Some of those accidents were described in a book published last year, entitled Command and Control. Author Eric Schlosser gives an account of an incident in September 1980 in Arkansas in which a maintenance engineer dropped a socket wrench into a silo holding a Titan II nuclear missile, igniting its fuel and triggering an explosion which sent the warhead flying. It landed near a road but did not detonate.

These are some of the incidents that illustrate how close the world has come to accidental nuclear apocalypse: Washington, June 1980: A faulty computer chip triggered a nuclear attack warning on the U.S., giving the impression that more than 2,000 Soviet missiles were on the way.

Cuban missile crisis: In October 1962, four nuclear-armed Soviet submarines were deployed in the Sargasso Sea at the height of the Cuban missile crisis. U.S. warships had warned Moscow that they would be practising dropping depth charges, but the message did not reach the submarines. With his communications cut off and believing himself under attack, one commander ordered a launch of nuclear warheads, declaring: “We’re going to blast them now.” He was persuaded to desist by his second-in-command.

Soviet Union, 1983: Shortly after midnight on September 25, an alert sounded at a Soviet satellite early warning station. The data suggested five intercontinental ballistic missiles were heading towards the country. Lieutenant Colonel Stanislav Yevgrafovich defied protocol by not reporting the incident to his superior, gambling that it was a false alarm. It turned out that sunlight glinting off U.S. territory had confused the satellite.

Russia, 1995: On January 25, Norwegian scientists launched a Black Brant rocket to study the aurora borealis over the Svalbard region. They warned Moscow but the message never reached the radar operators at the Russian early warning stations, who mistook the rocket for an incoming Trident submarine-launched missile. President Boris Yeltsin was discussing his decision with his top military commander when the rocket fell wide of Soviet territory. (Julian Borger is The Guardian’s diplomatic editor.)

© Guardian Newspapers Limited, 2014

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