And indeed, many of the criticality accidents listed on the Wikipedia page https://en.wikipedia.org/wiki/Criticality_accident https://en.wikipedia.org/wiki/Crit

And indeed, many of the criticality accidents listed on the Wikipedia page https://en.wikipedia.org/wiki/Criticality_accident https://en.wikipedia.org/wiki/Criticality_accident happened while handling fissile material in solution. There is a very interesting book on criticality accidents, which includes photographs and sketches on laboratory layout etc.: McLaughlin, T.P., Monahan, S.P., Pruvost, N.L., Frolov, V.V., Ryazanov, B.G. and Sviridov, V.I., 2000. A review of criticality accidents 2000 revision (No. LA-13638). Los Alamos National Lab., NM (US). https://www.orau.org/ptp/Library/accidents/la-13638.pdf https://www.orau.org/ptp/Library/accidents/la-13638.pdf