Device for irreversible marking of blood bags exceeding a critical temperature

摘要

The method involves attaching an inactive status indicator (1) on a blood bag in a heat or cool surrounding area. The indicator is conveyed into an active condition by treatment with rays. An active status indicator (2) remains at 10 degree centigrade in an active status, before reaching a critical core temperature (5) of erythrocyte concentrate. The active status indicator changes from the active status into a temperature-over exceeding status (3) with a pre-determined color change, during mounting of the latter indicator at warm surrounding area temperature and at exceeding core temperature.