The investigation and identification of a civil defense canister

A Civil Defense canister was found in a high school storage area with no radioactive labels or instructions. Initial screening with a 2" x 2" NaI detector indicated elevated count rates above background. Using field instruments with gamma peak analysis features and a laboratory counting system, the collective effort indicated that the contents included 238U and 235U. A Civil Defense Item Specification introduced later in the investigation show that the canister contained approximately 3.0 g of uranyl acetate. The specification also stated that the purpose of the canister was to determine the amount of radioactive material in water and solid, or liquid food samples.