An apparatus comprises a detection indicator, a housing, and an exoskeleton in which the housing nests. The detection indicator is configured to furnish a visual indication upon contact with a fluid responsive to a characteristic of the fluid. The housing comprises an interior chamber configured to receive the fluid and to provide contact between the fluid and the detection indicator. The housing is configured to removably engage a conduit coupled to a source of a fluid sample, which may be a lumen inserted into a patient to receive fluid therefrom. In methods for use with the apparatus, a sample is collected, a characteristic is measured by the apparatus, and the apparatus is disconnected so as to avoid leakage of the sample and exposure of personnel.
