Monitoring and tracking are integral to process compliance and product safety in pharmaceutical industry. They provide an effective way of making pharmaceutical products safe, ensuring the highest Degree of quality, and fulfilling regulatory regulations. One of many ways to monitor and track pharmaceutical processes is with Data Loggers. 

In this article, we will discuss how to select data loggers for your pharma applications, but first, let’s define data loggers.

What are Data Loggers?

Data loggers are electronic devices that monitor process variables and take records over time. They use different input mediums for measurement, such as sensors or probes, and can process variety of variables. The data logger can display in many forms, such as graphics, tabular form or analogue style. It can also act as a standalone indicator.

The readings in the data logger indicate a time-stamped view of the variable being recorded. The entire record can be tracked back to a different time value for viewing and analyzing. 

A single data logger can measure multiple variables, such as temperature, voltage, and current. It also has multiple probes, called channels, that allow it to take multiple measurements in a given time.

The data logger can also interface with the computer through software to view, visualize, and analyze the data. For this purpose, a communication cable and device software on the computer are required.

Input types

A data logger can take different input types. Some models allow only one kind of input, while others support multiple input types.

Some input types that can be used with the data logger include, but are not limited to, the following.

Temperature

Temperature is the most common type of input used that log the value of temperature against time with a fixed time interval. For measuring temperature, specific temperature sensors, such as thermocouples or RTDs, are connected to the logger. The sensors then measure the temperature sensed by the logger.

Temperature recording is commonly used in environmental monitoring, sterilization processes, and laboratories.

Humidity

These data loggers monitor humidity, and work in conjunction with temperature values.  

Pressure

A pressure data logger logs the value of pressure against time. It can log differential, atmospheric, and absolute pressure through suitable pressure sensor. 

Functions type

Data loggers are also classified according to function, which can include,

Standalone - they can work & operate independently of a computing or mobile device. They can record, display, and output data on the device. 

USB—These data loggers record values, but they require a USB connection to transmit the data for viewing and analyzing. 

Bluetooth Data Logger - These data loggers use Bluetooth to transmit the data for viewing & analyzing.

Cloud-Connected Data Logger—These data loggers transmit data to a cloud server. They must be connected to the Internet and any cloud service. This type allows real-time data availability using a web browser or mobile device.

What can go wrong if appropriate data loggers are not selected?

Let’s discuss some consequences of not appropriately selecting data loggers.

Inaccurate readings

The core function of a data logger is to measure relevant readings and log them in an appropriate format for record purposes. While sensors, internal circuitry, and signal conditioning errors affect the readings, a wrongly selected data logger can also cause the reading error.

Inappropriately selected data loggers will fail to detect and measure the correct value. This could also cause the data logger to log values outside of the acceptable limit, even if the readings lie within the acceptable threshold. 

Erratic records & documentation

The data logger provides records of logged values, which become part of the pharma process documentation, such as a Batch record. These records offer time stamped values of the variables during the entire process. 

An inappropriately selected data logger will fail to provide an accurate record due to reading errors. The record will be full of errors and lacking accuracy and quality. 

Failure to provide process insights.

In addition to records, data loggers also enable insights into the process. It can provide critical information such as deviation in standard process, time to completion, product status, and equipment performance. 

Failure to select appropriate data loggers will result in inaccurate data, which will not provide insight into the ongoing process and will not be correlated with the process, product, or performance.

Some tips on selecting a Data Logger for your pharma applications

Let’s discuss some tips for choosing a data logger for your pharma applications

What value do you want to measure?

Data Loggers can measure different process variables, and loggers designed for one variable cannot be used to log other variables. This is due to the difference in sensor and internal conditioning circuitry. 

To select a data logger, you must determine which variable you will measure. A temperature data logger will be the best choice if your process involves sterilization, heat, or cooling. The same goes for pressure and humidity variables.

What is the range of the measured value?

Pharma processes operate on the application of variables that have different operating ranges. Some processes require higher ranges, while others only require a low range of process variables. 

It is critical to determine the operating range of the parameters before purchasing the data logger. Because, a  processes can require different operating ranges. For example, steam sterilization requires temperatures up to 130°C. On the other hand, dry heat sterilization requires temperatures up to around 200°C.

The same applies to other parameters, i.e., pressure and humidity. 

Data storage

Data storage is an essential feature of a data logger, where logged variables for a particular process are stored for a defined period of time. Data storage allows retrieving the data at a later time for many purposes, such as data transfer, analysis, and recording. On the other hand, some data logger models do not have storage capability.

Different data logger models offer different storage capabilities, depending on the frequency of data collection. More frequent data collection will require more capacity, and vice versa.

Operating conditions

The pharmaceutical industry involves a variety of operating conditions for equipment, instruments, and personnel. Some processes are carried out clean & dust-free, while some have a concentration of dust & foreign particles. Some areas have easy access to electrical connections, while others include remote areas where finding them is difficult. 

When selecting a data logger, consider your area of application. If the area is a clean area where there is a high degree of cleanliness, consider a model that has less stringent protection capabilities. If the area has a higher concentration of dust particles, such as in a technical area, consider data loggers that have relevant IP ratings.

Similarly, consider whether the power connection is available in your area of application, and if not, consider battery-operated models. 

Connectivity

As mentioned earlier in this article, data loggers can also use connectivity technology to wirelessly transfer data to a computer or cloud storage for their relevant advantages. 

Required communication connectivity must be provided to use these technologies. Examples include the Internet and a computer with USB and Bluetooth capabilities. 

Real-time vs proactive 

Latest technology, such as Cloud storage and IoT, allows real-time data collection and data analytics. In latest technology, the data can be viewed as it is being collected. In another type, the traditional method, the readings are first logged and then downloaded or viewed at a later stage. 

Determine whether your process requires real-time data collection or proactive data collection. If your equipment or process has the latest IIoT systems, a real-time data logger will be best suited for your application and can be integrated with existing equipment and processing. On the other hand, if no real-time data is involved with existing equipment and processes, proactive data collection can be the best match.

21 CFR part 11

21 CFR part 11 is a regulatory requirement for electronic records, i.e., non-paper-based. The primary purpose of these guidelines is to ensure the security of the records generated through data loggers. Some aspects of 21 CFR part 11 include authenticity & authorization, audit trails, integrity of collected data, electronic signatures, and validation. 

Look for data logger models that offer 21 CFR part 11 compliance. Relevant software features and controls on the data logger can verify this.

Alarms

Data loggers log the process variables over time, which are further analyzed. However, some models also include an alarm system to alert users if the value drops below a threshold. 

Determine if your data logger requires an alarm system. This can be due to the process’s criticality or the quality department’s requirements. An alert system can be used in various ways, such as SMS, visual or audible indicator, a real-time alarm, or sending it directly to email or the Internet. 

Calibration

Calibration is a technique in which all the measurement points are verified against standard values, and this process is repeated at regular intervals. After calibration, it is necessary to maintain a record for regulatory body requirements and tracing purposes. 

Before purchasing a data logger for your pharma applications, make sure it has been calibrated. Check calibration certificates and obtain them along with the instrument.

About the Author

Muhammad Asim Niazi has a vast experience of about 11 years in a Pharmaceutical company. During his tenure he worked in their different departments and had been part of many initiatives within the company. He now uses his experience and skill to write interested content for audiences at PharmaSources.com.