Instrument Calibration

What is instrument calibration?

Instrument calibration is the process of comparing a measurement instrument to a known standard to determine the accuracy of the instrument. The standard is usually a reference instrument that a certified laboratory has calibrated.

The purpose of calibration is to ensure that the instrument is providing accurate measurements. Calibration can be of different levels based on their accuracy, such as primary, secondary, and in-house calibration. 

The primary calibration is the most accurate, performed in a certified laboratory environment. In contrast, in-house calibration is the least accurate type, performed by the user of the instrument using a reference standard that a professional does not calibrate. 

The calibration process’s frequency depends on the instrument’s criticality and the environment in which it is used. However, as a standard practice, every instrument should be calibrated at least once a year for normal conditions and more than once for hash conditions. 

What are the types of instrument calibration?

Based on the instrument that is being calibrated, these are the different types of instrument calibration. 

1. Electrical calibration

Electrical calibration is a process where electric instruments like data loggers, muti-meters, insulation testers, loop testers, etc., are calibrated to ensure the accuracy of their key properties like resistance, voltage, inductance, capacitance, etc. 

2. Mechanical calibration

Mechanical instruments like accelerometers, gauges, and scales are prone to drift as a result of heavy usage. So to maintain their accuracy, mechanical calibration is crucial. Some aspects that are calibrated in the process include the mass, density, torque, vibration, flatness, and other significant properties of the instrument. 

3. Flow calibration 

Industries that use different flow meters and flow sensors, such as laminar flowmeters, gas, air rotameters, turbine meters, etc., use this calibration type to ensure accurate measurements. 

4. Pipette calibration

Pipette calibrations are performed to check and maintain the precise pipetting results in the laboratories. 

5. Pressure calibration

Digital pressure gauges, transducers, transmitters, barometers, and similar pressure-measuring instruments require time-to-time calibration to maintain high accuracy. To achieve that, pressure calibration is carried out using different calibrators. 

6. Temperature calibration 

Devices such as data acquisition systems, thermometers, furnaces, infrared meters, thermal cameras, etc., require temperature calibration in a controlled environment to run without interruption. 

What is the importance of instrumentation calibration? 

Instrument calibration is considered a critical process in various fields, from research to manufacturing to engineering and quality control. Here are some key reasons why it is looked up so highly. 

1. Achieving accuracy and reliability

Over time, instruments can drift or deviate from their initial calibration due to environmental factors, wear and tear, or aging components. Calibration ensures that instruments provide accurate and reliable measurements. 

2. Quality assurance

In industries where precise measurements are essential, such as pharmaceuticals, aerospace, or automotive, calibration plays a vital role in quality assurance. Calibrated instruments help maintain product consistency, reliability, and compliance with industry standards and regulations.

3. Improve traceability

Calibration establishes a traceable measurement chain. By comparing the instrument’s measurements to traceable standards, calibration provides a documented record of accuracy, allowing for traceability to national or international measurement standards.

This is a crucial practice for audits, certification, and other legal compliances. 

4. Process optimization

Calibration helps identify and rectify any deviations in an instrument’s performance. By detecting and correcting measurement errors, calibration enables process optimization and minimizes the risk of faulty or defective products. 

5. Safety

Calibration plays a crucial role in ensuring safety in various industries. Instruments used in monitoring, control, and safety systems must provide accurate measurements to prevent accidents, hazards, or potential harm.

6. Cost savings

Calibration can prevent costly errors, waste, and rework. Inaccurate measurements can lead to faulty production, rejected products, or expensive recalls.