A cold chain is a logistic system that provides a series of refrigerating facilities aimed at maintaining certain goods at a pre-requisite, constant (usually low) temperature from the point of production to the point of sale or usage. Proper execution of cold chains is vitally important to many different industries, including the food, pharmaceutical and the chemical industries. Any product that needs to be maintained at a constant temperature in order to retain its optimal effectiveness requires the use of a flawless, unbroken cold chain. Using temperature indicator labels will assist in the monitoring of this process.

The role of a cold chain is vital to the industries it serves. An effective cold chain will increase product longevity, nullify contamination and bacterial infestation, and minimize waste and expiration of stock before it can be delivered or sold. A high-quality cold chain also helps to improve product reliability and to ensure customer satisfaction.

The most common and widely implemented cold chain is in the temperature range of 2–8°C, as this range is used in preservation and transportation of a wide range of goods, from food to pharmaceuticals. This mandates that the temperature be maintained above 2°C and below 8°C at all times. If it fluctuates outside of this range it will render the product unusable.

A cold chain may consist of several different types of facilities for storage and means of transportation. It may include pre-cooling facilities, cold storage facilities for warehousing, refrigerated carriers (such as trucks or rail cars), thermally insulated packaging and the kind of information management system that is required to monitor, track and trace a certain product.

Monitoring a product’s temperature constantly while in transit is absolutely critical in order to prevent the product from losing some of its properties. For example, frozen foods may not remain edible if exposed to higher temperatures, even if only for a brief period of time. In the pharmaceutical industry, for example, a constant temperature is essential for keeping certain drugs from losing their effectiveness, or even worse, from becoming poisonous.

Transporting vaccines to remote areas, particularly in Third World, poverty-stricken regions where transportation may not have been adequately developed, is extremely difficult. Making sure the drugs stay refrigerated throughout what may be a very long haul, with zero temperature breaches, is absolutely critical. In such cases the importance of proper monitoring equipment rises exponentially. Vaccines are most needed in tropical regions because viruses thrive in hotter climates. In extreme heat, the shelf life of several drugs and vaccines is reduced dramatically as compared to colder, more sterile climates.

Another problem with temperature-controlled transportation that has recently come to light is that some refrigerator-truck drivers have been known to turn off the refrigeration while driving at night or while taking a break. This makes good economic sense to them because refrigeration is expensive in terms of energy consumption and fuel costs. As long as the goods arrive at their destination at the required temperature, there is no way for customers to know whether or not there has been a temperature breach. This kind of malpractice can render vaccines useless and even endanger lives on a massive scale.

This is where proper monitoring equipment comes in. Temperature monitoring labels and indicators let customers know whether or not there has been a temperature breach. Some of these products, like Timestrip, run battery-free and can be transported and stored at any temperature range, making them very cost-effective and easy to use. They are built to be tamper proof, so, once activated, they will provide a faithful, unbroken log of the temperature ranges that they’ve travelled through without deviation. They also will let a customer know how many breaches in temperature may have occurred. Such products increase the overall reliability of vaccines and may help to save lives in the long run.