'Condition-based' monitoring of cold-chain shipments might provide better operational performance

A shift from datalogging as a passive monitor to a shipment validation

In the hotly contested market for dataloggers, temperature indictors and related electronics for monitoring conditions during a life-sciences cold-chain shipment, one vendor, Berlinger & Co. (Ganterschwil, Switzerland; US HQ in Marietta, OH), thinks it has an edge: its CLm and related electronic monitors adjust the frequency of their temperature measurements based on the readings they collect. When temperature starts rising or falling, the frequency of readings accelerates; when conditions are stable (as they are for perhaps 95% of a shipment’s duration) readings stick to a predetermined schedule.

Conventional dataloggers (most of which are meant to be single-use devices, equipped with small batteries) are relatively dumb devices—they collect and record data. When a shipment is received, the data are downloaded and a determination is made whether the shipment was within operating parameters (generally, 2-8°C). Vendors limit the frequency of readings to preserve battery life. But according to Patrick McGrath, GM at Berlinger, that requires an analysis of each and every temperature excursion—its peak and duration, and review of other pertinent conditions. The administrative work necessary to do this analysis can amount to several hundred dollars per excursion, he says, “But half or more of these excursions are allowable, based on their short duration.” Another problem is that if the datalogging interval is set too broadly (most take a reading every 15 min.), the actual high or low points could be missed.

There is a subtle point being espoused here: to convert the datalogger from a simple recording device, to one that validates a shipment. Berlinger (and some other vendors) are pointing to the real measurement that should be taken: “time out of refrigeration” (TOR); the electronics to provide this measurement are available, but typically haven’t been used this way by shippers. McGrath says that informal conversations with regulators in various countries have been accepting of this concept. This trend is also seen in high-end, reusable monitors, which measure vibration and exposure to light, and provide geolocation, such as the SensAware monitor from FedEx, the SmartBox of DB Schenker, or the Cargo Companion service of Southwest Air Cargo. (By contrast, the low end of temperature monitoring—which is in common use in cold chain delivery—is a temperature indicator that does nothing more than turn color when exposed to excessive heat or cold).