Optional Visual pH Color Change Result
The 1491 BI is normally discarded after the fluorescent result has been recorded. If,
however, special studies are desired, 1491 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
24 hours. Any observation of a yellow color within the vial indicates a positive result.
In the case of a processed 1491 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 24 hours.
Storage
• Best stored in original box under normal room conditions: 59-86ºF (15-30ºC),
35-60% relative humidity (RH).
• Do not store 1491 BIs near sterilants or other chemicals.
Disposal
Dispose of used 1491 BIs according to your health care facility policy. You may
wish to steam sterilize any positive biological indicators at 121°C/250°F for at least
30 minutes, or at 132°C/270°F for 10 minutes in a gravity displacement steam
sterilizer, or at 132°C/270°F for 4 minutes in a dynamic-air-removal steam sterilizer
prior to disposal.
Explanation of Symbols
Catalogue Number
Caution, see instructions for use
Do not reuse
Use by date
Batch code
Manufacturer
Date of manufacture
Product is designed for use with steam sterilization cycles.
