Abstract: An instrument kit includes a photometric instrument and a standardizing ampoule. The standardizing ampoule includes a machine readable code that is recognized by the instrument when the ampoule is inserted to initiate a standardizing routine. An analysis kit includes an optical filter assembly and a sample ampoule to be used with the instrument. The filter assembly also includes a machine readable code that is detected by the instrument when inserted to identify the particular test to be conducted by the instrument. The instrument automatically applies the relationship between detected light and concentration of a substance for the particular test and displays the sample concentration in numeric digital form. The instrument operates automatically, and there are no buttons or other external input devices.

Abstract: An article particularly useful for Chemical Oxygen Demand (COD) tests includes an ampule, a resealing cap, and a protective sheath. The ampule includes a segment along its neck that is detachable for allowing introduction of a sample. The cap is used for resealing the neck after introduction of a sample, and the detachable segment is located at a narrow diameter portion of the neck so that the expulsion force on the cap generated by interior pressure is small. A flexible sheath is provided to protect the neck during shipment and to assist in removing the detachable segment.