Litmus paper
Litmus paper was a piece of medical equipment used to collect a liquid sample.

In 2151, T'Pol used a piece of litmus paper to collect a sample of the water supply on the Akaali homeworld. This piece of paper was later analyzed by Doctor Phlox under his microscope in sickbay aboard  and Phlox told that the water supply was contaminated with the industrial lubricant tetracyanate 622. ()

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Medical equipment