are maintaining temperatures in line with regulatory requirements. The data can also be used to determine the “worst-case” location for monitoring, says Bennett, which can then be the point where a LabWatch sensor is installed to perform permanent, constant monitoring until the next required revalidation. Facilities must typically be revalidated every two years.

The approach using the wire-based Validator 2000 system has lots of limitations, however. In warehouses and other areas where people must work, the thermocouple wires can get in the way, and are frequently damaged, Bennett notes. And if a facility is very large, it becomes impossible to string the temporary wires for long enough distances, forcing a fallback to use of chart recorders, he adds.

Further, when wired thermocouple systems are practical for use, they are time- and labor-intensive to put up. “You’re up and down a lot of ladders,” says Bennett. “It takes easily a couple of hours to set up, and it’s the same thing removing it once the study is completed.”

Wireless validation

KV Pharmaceutical’s validation group expects to overcome many of these problems, however, by converting to a wireless system for temperature map validation studies. The company is currently testing a portable, wireless mesh network-based validation system, also from GE Sensing, known as the RF Valprobe. And the early results look promising.

Further, set-up is significantly simplified. “It’s a whole lot easier to install a sensor and have it start recording data, compared to trying to string thermocouple wires everywhere. And of course, there’s much less chance of something happening to the sensor,” Bennett adds. “Basically, all you do is plug in the base station, and then place the wireless sensors wherever you need them,” he notes. “When you’re done, you download the data to your computer, turn it off, and take it somewhere else to do another study.” Bennett expects ROI on the RF Valprobe system to be in the neighborhood of one year, based largely on labor and maintenance savings.

In general, Bennett says, he is well pleased with the wireless technology. He has replaced several wireless sensors used with LabWatch systems due to water damage that occurred during washdowns, he notes. But that situation should improve, Bennett says, with “a little bit of training to let people know what they are and the proper care for them.”

 Reliability and security of the wireless technology is strong, Bennett believes. And so far, regulators seem to agree. “It’s very easy to defend data integrity with these systems,” he says. “You can show inspectors a report from a Validator 2000 and they pretty much won’t even question it. And I think the same thing generally holds true with the LabWatch and Valprobe data,” he adds, “because the same rigor has gone into ensuring data integrity.”  

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