Steam explosion major cause of human fatalities in volcanic eruptions. The 1986 Chernobyl nuclear disaster in Soviet Union was feared to cause major steam explosion (and resulting Europe-wide fallout) upon melting the lava-like nuclear fuel through the reactor's basement towards contact with residue fire-fighting water and groundwater. The threat was averted by frantic tunneling underneath the reactor in order to pump out water and reinforce underlying soil with concrete. When a pressurized container such as the waterside of a steam boiler ruptures, it is always followed by some degree of steam explosion. A common operating temperature and pressure for a marine boiler
Peaceful nuclear explosion many of the "tests" were considered economic applications, not tests, in the Nuclear Explosions for the National Economy program. These included one 30 kiloton explosion being used to close the Uzbekistani "Urtabulak" gas well in 1966 that had been blowing since 1963, and a few months later a 47 kiloton explosive was used to seal a higher pressure blowout at the nearby "Pamuk" gas field. (For more details, see Blowout (well drilling)#Use of nuclear explosions.) The public records for devices that produced the highest proportion of their yield via fusion-only reactions are possibly the Taiga Soviet peaceful nuclear explosions of