If the indicator is correctly activated false positives are extremely unlikely as the blue dye can only melt at or above certain temperatures. It is important to lower the indicator to its STOP temperature after activation and only attach it to a product, carrying card or material that is already at or below the STOP temperature to avoid premature indication.
They are suitable for many situations when elevated temperatures can create problems for a product. Common applications are frozen or chilled foods, medicines, vaccines, adhesives and chemicals. A common use is to identify the elapsed time of temperature abuse during shipping. Another is for products which are taken repeatedly in and out of their ideal storage conditions for temporary use, like lab chemicals. One or two excursions might not be problematic, but Timestrip® PLUS shows the cumulative time of all excursions and this can be used to trigger a timely replacement of the product.
It is a single use temperature indicator in a self-adhesive format. It indicates if temperature has risen to breach a defined threshold and it records the cumulative elapsed time of all such breaches. Each product in the range is engineered to respond to a different threshold temperature so customers can choose the product that best suits their needs.
There are fundamental differences. Data loggers are expensive and typically are designed to go on large shipments. They are not an immediate tool as they need to be returned/connected for the data to be read and acted on, and they have to be used repeatedly to justify the expense. They also require power. Timestrip® PLUS indicators are less expensive, require no power, are single use and can be instantly read by the end user. They have unique serial numbers to ensure the traceability of each indicator to avoid the potential for manipulation across the distribution chain. As well as being effective for large shipments, Timestrip® PLUS are small light and cost effective enough to be used at the carton or single unit level. Using them at multiple points within a shipment or container can isolate unacceptable temperature pockets. Data loggers provide a full history of temperature from the time of activation. Timestrip® PLUS records how long a product has been above its threshold temperature (up to the maximum printed on the scale - usually 8 or 12 cumulative hours) but cannot tell you when the breach or breaches occurred. Timestrip® PLUS is most often used to monitor and validate the ‚ 'last-mile' of a cold chain or other temperature environment, in other words, when the product is close to its eventual use. In some cases data loggers and Timestrip® PLUS indicators may be used in complementary ways to help monitor temperatures.
A blue dye housed in a blister is held adjacent to a micro-porous membrane. Upon squeezing the activation button the liquid dye comes out of the blister and into contact with the membrane. If the temperature of the product is below the stated ‚ STOP temperature, the blue dye changes state to solid form, and it is unable to move through the membrane. If the temperature rises to or above the threshold temperature, the dye changes to liquid form and moves at a precise rate through the membrane. Its progress is irreversible and the distance it travels through the viewing window indicates the cumulative time the indicator has been exposed to the threshold temperature or above. Once activated, Timestrip® PLUS will keep monitoring temperature for days, weeks or months, depending on your needs. During that time it will record how long any temperature breaches last. Here is an example. An 8ºC Timestrip® PLUS was chosen to monitor a shipment which would take 3 weeks to arrive. When the shipment arrived, the indicator showed 4 hours of 8ºC breach. This breach could have happened in one long event or from a series of shorter breach events across the 3 weeks. The 8ºC Timestrip® PLUS could have indicated up to 8 hours of temperature breaches during that 3 weeks.
The melting point of a solid is the temperature at which it changes state from solid to liquid. The freezing point (or crystallization point) is the temperature at which a liquid changes to a solid. For certain substances the melting and freezing point are not the same and the freezing point is lower than the melt point. This behaviour is called hysteresis. At the STOP point (freezing point) the dye can't move. At the melt point the dye moves and indicates a threshold breach.
No. Unlike some other threshold temperature products, Timestrip® PLUS does not require pre-conditioning. You need to activate above the product's threshold temperature, as you cannot squeeze the dye out of the blister if it is in solid form. Immediately after activation, stop the progress of the dye by placing the indicator below its STOP temperature. You can adhere the Timestrip immediately to a product or carrying card which is below the STOP temperature. Alternatively place the activated indicator in an environment much colder than the STOP temperature for a short period of time.
No, unlike some other threshold temperature products, Timestrip® PLUS can be stored inert at ambient temperatures and only activated when needed.