Simplified methods of estimating the results of accidental solution excursions in tanks have been developed. With these methods, an estimate of the number of fissions in the burst, total fissions, or maximum power level can usually be obtained with a desk calculator. The equation parameters are tank diameter, height, and fill rate. The fissile material concentration is not required since, in each case, the “worst-case” concentration was assumed in the derivation of the equation. These methods are sufficiently accurate for most calculations required for safety analysis reports and process plant design. The severity of an excursion can be limited by several methods which include criticality alarm activated shut-off valves in the feed lines, remote tank drain capability, minimizing tank size, etc.