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Interpretation of Results:
Fluorescent Results
The positive control (unprocessed) 1492V BI must provide a positive fluorescent result (+ on the
490 or 490H Auto-reader LCD display). Processed 1492V BI results are not valid until the positive
control reads fluorescent positive. The positive control should read positive (+ on the LCD display)
at or before 1 hour. If the positive control reads negative (- on the LCD display) at 1 hour, check
the Auto-reader Operator’s Manual Troubleshooting Guide. Retest the Auto-reader with a new
positive control.
With processed 1492V BIs, a positive (+ on the LCD display) result indicates a sterilization
process failure. A final negative (- on the LCD display) result for the processed 1492V BI after the
specified incubation time indicates an acceptable sterilization process.
Act immediately on any positive results for processed BIs. Determine the cause of the positive BI
following facility policies and procedures. Always retest the sterilizer and do not use sterilizer for
processing loads until qualification testing yields satisfactory results (typically three consecutive
cycles with negative BI results and three consecutive cycles with passing Bowie-Dick
test results).
Optional Visual pH Color Change Result
The 1492V BI is normally discarded after the fluorescent result has been recorded. If, however,
special studies are desired, 1492V BIs may be further incubated for a visual pH color change
result. After activation and during incubation, the white Nonwoven Material will absorb the
bromocresol purple indicator, the pH-sensitive indicator dye in the growth media, and appear
blue. In the case of the positive control BI a yellow color change of the growth media and/or
Nonwoven Material will appear within 48 hours. Any observation of a yellow color within the vial
indicates a positive result.
In the case of a processed 1492V BI, a media and/or Nonwoven Material color change from
purple to yellow indicates a sterilization process failure. A negative pH color change result, i.e.,
media and Nonwoven Material remain purple/blue, can be assessed at 48 hours.
Storage
• Best stored under normal room conditions: 59-86ºF (15-30ºC).
• Store away from direct sunlight. Do not store challenge packs near sterilants or
other chemicals.
Disposal
Dispose of used 1492V BIs according to your health care facility policy. You may wish to steam
sterilize any positive biological indicators at 270°F (132°C) for 4 minutes or at 275°F (135°C) for
3 minutes in a dynamic-air-removal steam sterilizer prior to disposal.
Explanation of Symbols
Do not reuse
Use by date
Batch code
Manufacturer
Date of manufacture
Product is designed for use with steam sterilization cycles.
Catalogue Number
