A cassette of tympanic thermometer probe covers includes a frame and probe covers releasably attached to the frame. The probe covers can be individually attached over a probe of a tympanic thermometer to protect the probe from contamination. The probe covers are constructed to releasably secure themselves to the probe. The force required to secure the probe covers to the frame is less that the force which is required to detach the probe covers from the frame so that the probe cover is held by the frame while being attached to the thermometer probe. The probe cover is connected to the frame by frangible connections that are arranged to inhibit pivoting of the probe cover when being attached to the thermometer probe. A method of securing a probe cover to a probe of a tympanic thermometer is also disclosed.
