Upgrading the Clipboard with Data Loggers to Document Cold Storage Temps

Automated loggers work with the user’s schedule and can eliminate many risks. The user specifies intervals and there is no need to remember to physically walk around to the data loggers before they fill up. A network connected data logger is extremely reliable because it will notify the user through a network or cellular connection if temperatures go out of a pre-selected range. Depending on the network infrastructure and needs, loggers can connect to a wired LAN connection or with Wi-Fi to connect to the cloud.

If using automated data loggers with a wireless connection, users will need a radio connection to a router, data collector, or access point of some kind. This can be problematic with thick metal side walls, where the transmission range is dramatically limited, but there are ways to get around it.

One solution is to place the logger with its integrated antenna outside the freezer and run the sensors through the door gasket. Thin 2-millimeter diameter thermistor sensors are needed. However, if the sensor is not placed inside the walk-in by any significant margin, the sensor can be subject to thermal transitions when the doors open. Some loggers or software ignore those temperature transients caused by doors opening. Typically, this is a setting, but be sure to have that setting available; otherwise there will be false readings.

With large walk-in refrigerators, people may want to monitor a spot far away from the door or multiple points inside. To solve the former, thermocouple sensors with a long wire to feed the sensor inside can measure the temperature at distances far from the logger itself. Measuring temperatures at multiple locations can be accomplished with a two-channel logger and long thermocouples or wireless loggers that connect using a 900 MHz signal instead of the average 2.4 GHz Wi-Fi signal. Those can be set up in multiple locations to then transmit to a repeater mounted on the outside wall of the walk-in. The repeater would then relay the signal to the access point, data collector, or base unit. The repeater solves the issue of the interrupted signals due to the metal walls of the walk-in.

Ensuring Compliance

Those storing food in cold chain must also be fully aware of the Food Safety and Modernization Act (FSMA). When food is frozen, microbes go into a dormant stage, but when the food begins to thaw, microbes become active again and start multiplying to levels that can lead to foodborne illness. FSMA states that it is the federal government’s right to inspect any food handling location at any time, so safe temperature data need to be proven. Data loggers facilitate thorough inspection and can allow for quicker compliance.

One way to track all temperature data over time to share with regulators is with WebStorage Service, T&D Corp.’s free cloud storage service. WebStorage Service stores temperature data collected by T&D data loggers. Data are retrievable and charted and can be viewed later. Food handlers can prove their temperature data and show regulators their safe practices.

FSMA also requires food handlers to develop a plan that meets the guidelines for Hazard Analysis and Critical Control Points (HACCP), which should involve an automated data logger. Issues with data entry, misreading, and misinformation are the responsibility of the food handler, and failure to comply with these guidelines can result in seizure, injunction, and recalls, all of which can damage the reputation of the entire supply chain.

To adhere to HACCP, food handlers must establish critical limits for each CCP. This includes monitoring activities to ensure that the process is under control at each point in the food manufacturing process. Data loggers are essential to this adherence. Automated data loggers alert users via email, text, or push notification when temperature measurements go out of the set range. Users can know the exact moment temperature goes out of safe levels and the problem can be fixed in real time, negating the risk of ruining supplies.

A Refrigeration Mishap Example

The need for flexible, automated data loggers to monitor and alert can be understood through Southern Wine & Spirits’ refrigeration mishap. The winery hosts events for its visitors where they can test different beverage and food pairings. That means that the company needs to store food, such as cheese, vegetables, fruit, and seafood.