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Isomers produced by spontaneous fission of ²⁵²Cf were measured with the VESPA setup, composed of LaBr₃(Ce) detectors for fast γ-ray spectroscopy and an ionization chamber for detecting fission fragments. Identification of the isomers was derived from fission fragment-γ-γ coincidences. This paper presents the half-lives of 41 isomeric states measured with this setup, from less than a nanosecond up to tens of microseconds. Short-lived isomers in ⁹⁴Rb, ¹⁰⁸Tc, and ¹⁴⁷Ce are reported for the first time. In addition to this half-life analysis, the isomers are used to develop and test a nuclear charge calibration of the ionization chamber.