Cryoguard™ Thermal Exposure Indicators signal thermal exposure or temperature abuse of heat sensitive materials. These thermal exposure monitors have many applications. They function as thermal exposure sensors for monitoring perishable materials, such as frozen blood plasma, stem cells, sperm, tissue samples, clinical samples and premixed epoxy adhesives. The indicators can also be used to detect failures or fluctuations in refrigeration or freezers.

Cryoguard Thermal Exposure Indicators are available with 4 different pre-set "signal" temperatures: -40°C, -70°C, -100°C and -120°C, which correspond to a variety of scientific, medical and commercial applications. When an indicator is exposed to temperatures above its signal temperature, it irreversibly changes color from green to red. This irreversible color change is what signals temperature abuse of cryopreserved materials that otherwise might go undetected. Indicators should be chosen with signal temperatures at least 30°C higher than that of the environment being monitored.