Why use software for calibration management?

Every plant has some sort of system in place for managing calibration operations and data, but the different methods for doing it vary greatly in terms of cost, quality, efficiency and accuracy of data.

Plant instrumentation devices such as temperature sensors, pressure transducers and weighing instruments require regular calibration to ensure they are performing and measuring to specified tolerances. However, different companies from a diverse range of industry sectors use very different methods for managing these calibrations. These methods differ greatly in terms of cost, quality, efficiency and accuracy of data and their level of automation.

Calibration software is one such tool that can be used to support and guide calibration management activities, with documentation being a critical part of this. But in order to understand how software can help process plants better manage their instrument calibrations, it is important to consider the typical calibration management tasks that companies have to undertake. There are five main areas here, comprising planning and decision making, organisation, execution, documentation and analysis.

Careful planning and decision-making is important. All plant instruments and measurement devices need to be listed and classified into ‘critical’ and ‘non-critical’ devices. Once this has been agreed, the calibration range and required tolerances need to be identified. Decisions then need to be made regarding the calibration interval for each instrument. The creation and approval of standard operating procedures (SOPs) for each device is then required, followed by the selection of suitable calibration methods and tools for execution of these methods. Finally, the company must identify current calibration status for every instrument across the plant.

The next stage, organisation, involves training the company’s calibration staff — typically maintenance technicians, service engineers, process and quality engineers and managers — in using the chosen tools and how to follow the approved SOPs. Staff then have to be organised and assigned to actually carry out the scheduled calibration tasks.

The execution stage involves supervising the assigned calibration tasks. Staff carrying out these activities must follow the appropriate instructions before calibrating the device, including any associated safety procedures. The calibration is then executed according to the plan, although further instructions may need to be followed after calibration.

The documentation and storage of calibration results typically involves signing and approving all calibration records that are generated. The next calibration tasks then have to be scheduled, calibration labels need to be created and pasted, then created documents copied and archived.

Based on the calibration results, companies then have to analyse the data to see if any corrective action needs to be taken. The effectiveness of calibration needs to be reviewed and calibration intervals checked. These intervals may need to be adjusted based on archived calibration history.

Documentation

Documentation is a very important part of a calibration management process. ISO 9001:2000 and the FDA both state that calibration records must be maintained and that calibration must be carried out according to written, approved procedures.

This means an instrument engineer can spend as much as 50% of their time on documentation and paperwork — time that could be better spent on other activities. This paperwork typically involves preparing calibration instructions to help field engineers; making notes of calibration results in the field; and documenting and archiving calibration data.

Imagine how long and difficult a task this is if the plant has thousands of instruments that require calibrating on at least a six-monthly basis. The amount of manual documentation increases almost exponentially!

When it comes to the volume of documentation required, different industry sectors have different requirements and regulations. In many industries, the number of calibrations carried out per year can be in the thousands. This equates to a huge amount of paperwork for those process plants.

Companies require some sort of software tool to help them manage their instrument calibration processes and all associated documentation. However, the picture in reality can be very different.

Only a quarter of companies use calibration software

In Beamex’s own Calibration Study carried out in 2007, a mere 25% of companies with 500+ employees said that they use specialist calibration management software. Many other companies said that they relied on generic spreadsheets or databases for this, while others used a calibration module within an existing computerised maintenance management system (CMMS). A significant proportion (almost 20%) of those surveyed said they used a manual, paper-based system.

In a recent survey conducted by Control Magazine, 40% of companies surveyed said that they calculated calibration intervals by using historical trend analysis — which is encouraging. However, many of these firms said they were doing it without any sort of calibration software to assist them. The other 60% of companies determined instrument calibration intervals based on either the manufacturer’s own recommendation, or they used a uniform interval across the plant for all instruments. Neither method is ideal in practice. Companies could save so much time and reduce costs by using calibration management software to analyse historical trends and calibration results.

Using software for calibration management enables faster, easier and more accurate analysis of calibration records and identification of historical trends. Plants can therefore reduce costs and optimise calibration intervals by reducing calibration frequency when this is possible, or by increasing the frequency where necessary.

For example, for improved safety, a process plant may find it necessary to increase the frequency of calibration of some sensors that are located in a hazardous, potentially explosive area of the manufacturing plant.

Just as important, by analysing the calibration history of a flowmeter that is located in a ‘non-critical’ area of the plant, the company may be able to decrease the frequency of calibration, saving time and resources. Rather than rely on the manufacturer’s recommendation for calibration intervals, the plant may be able to extend these intervals by looking closely at historical trends provided by calibration management software. Instrument ‘drift’ can be monitored closely over a period of time and then decisions taken confidently with respect to amending the calibration interval.

Paper-based systems

These systems typically involve handwritten documents. Typically, this might include engineers using pens and paper to record calibration results while out in the field. On returning to the office, these notes are then tidied up or transferred to another paper document, after which they are archived as paper documents.

While using a manual, paper-based system requires little or no investment, it is very labour intensive and means that historical trend analysis becomes very difficult to carry out. In addition, the calibration data is not easily accessible. The system is time consuming, soaks up a lot of resources and typing errors are commonplace. Dual effort and re-keying of calibration data are also significant costs here.

In-house legacy systems

Although certainly a step in the right direction, using an in-house legacy system to manage calibrations has its drawbacks. In these systems, calibration data is typically entered manually into a spreadsheet or database. The data is stored in electronic format, but the recording of calibration information is still time consuming and typing errors are common. Also, the calibration process itself cannot be automated. For example, automatic alarms cannot be set up on instruments that are due for calibration.

Calibration module of a CMMS

Many plants have already invested in a computerised maintenance management system (CMMS) and so continue to use this for calibration management. Plant hierarchy and works orders can be stored in the CMMS, but the calibration cannot be automated because the system is not able to communicate with ‘smart’ calibrators.

Furthermore, CMM systems are not designed to manage calibrations and so often only provide the minimum calibration functionality, such as the scheduling of tasks and entry of calibration results. Although instrument data can be stored and managed efficiently in the plant’s database, the level of automation is still low. In addition, the CMMS may not meet the regulatory requirements (eg, FDA) for managing calibration records.

Calibration software

With specialist calibration management software, users can be provided with an easy-to-use Windows Explorer-like interface. The software manages and stores all instrument and calibration data. This includes the planning and scheduling of calibration work; analysis and optimisation of calibration frequency; production of reports, certificates and labels; communication with smart calibrators; and easy integration with CMM systems such as SAP and Maximo. The result is a streamlined, automated calibration process which improves quality, plant productivity and efficiency.

Operational benefits of using calibration software

With software-based calibration management, planning and decision making are improved. Procedures and calibration strategies can be planned and all calibration assets managed by the software. Position, device and calibrator databases are maintained, while automatic alerts for scheduled calibrations can be set up.

Organisation also improves when using calibration software because the system no longer requires pens and paper. Calibration instructions are created using the software to guide engineers through the calibration process. These instructions can also be downloaded to a technician’s handheld documenting calibrator while they are in the field.

Using software-based calibration management systems makes execution more efficient and eliminates errors. When used in conjunction with documenting calibrators, this means that calibration results can be stored in the calibrator’s memory, then automatically uploaded back to the calibration software. There is no re-keying of calibration results from a notebook to a database or spreadsheet. Human error is minimised and engineers are freed up to perform more strategic analysis or other important activities.

Documentation is also improved. The software generates reports automatically and all calibration data is stored in one database rather than multiple disparate systems. Calibration certificates, reports and labels can all be printed out on paper or sent in electronic format. Analysis becomes easier too, enabling engineers to optimise calibration intervals using the software’s History Trend function.

Also, when a plant is being audited, calibration software can facilitate both the preparation and the audit itself. Locating records and verifying that the system works is effortless when compared to traditional calibration record keeping.

Regulatory organisations and standards such as FDA and ISO place demanding requirements on the recording of calibration data. Calibration software has many functions that help in meeting these requirements, such as Change Management, Audit Trail and Electronic Signature functions. The Change Management feature in Beamex’s CMX software, for example, complies with FDA requirements.

Business benefits

For the business, implementing software-based calibration management means overall costs will be reduced. These savings come from the now-paperless calibration process, with no manual documentation procedures. Engineers can analyse calibration results to see whether the calibration intervals on plant instruments can be altered. For example, those instruments that perform better than expected may well justify a reduction in their calibration frequency.

Plant efficiencies should also improve, as the entire calibration process is now streamlined and automated. Manual procedures are replaced with automated, validated processes, which is particularly beneficial if the company is replacing a lot of labour-intensive calibration activities. Costly production downtime will also be reduced.

Even if a plant has already implemented a CMMS, calibration management software can be easily integrated into this system. If the plant instruments are already defined on a database, the calibration management software can utilise the records available in the CMMS database.

Summary

Every type of process plant, regardless of industry sector, can benefit from implementing specialist calibration management software. Compared to traditional, paper-based systems, in-house built legacy calibration systems or calibration modules within CMM systems, using dedicated calibration management software results in improved quality, increased productivity and reduced costs of the entire calibration process.

AMS Instrumentation & Calibration Pty Ltd
www.ams-ic.com.au

Beamex
www.beamex.com