What is calibration?
Calibrating a piece of equipment or system involves comparing its reading with another piece of equipment that has been calibrated and referenced to a predetermined set of criteria. Equipment calibrated in accordance with ISO/IEC 17025 should be directly traceable to the reference equipment.
Calibration gives equipment users confidence that their equipment readings satisfy standards and legislation in the region of operation. This is because the aim of calibration is to adjust the equipment’s accuracy to another equipment’s readings that are well calibrated.
Why is calibration important?
An equipment reading’s accuracy directly impacts the performance of that equipment. A well calibrated instrument is more likely to perform reliably than a poorly calibrated instrument. A tangible example of this includes calibrated equipment being more efficient in weighing materials used to build a product than uncalibrated equipment. This reduces waste material and hence boosts cost savings.
Apart from operational efficiency, calibration extends the life of equipment. It is also cheaper to use calibrated equipment rather than faulty equipment in the long run because there is a reduced chance of sudden equipment failure.
Calibration must be performed regularly because the accuracy of equipment and instruments deviates over time. Some reasons for this inevitable deviation include changes to the environment (temperature, humidity, barometric pressure etc.), mechanical or electrical shocks, or exposure to other extreme conditions.
Types of calibration
Calibration can be broadly broken into 5 categories, depending on the instrument and what the quantity it measures. Although this is not an exhaustive list, most calibrations carried out by technicians fall within one of the five types described below.
1) PRESSURE CALIBRATION
Pressure calibration is important in many industries that work with gasses, steam and hydraulics. Common pressure instruments that are regularly calibrated are:
- Digital Pressure Gauges
- Analogue Pressure Gauges
- Pressure Sensors and Transducers
- Barometers
2) TEMPERATURE CALIBRATION
Temperature calibration is crucial in industries that work with controlled temperature environments. Temperature is typically calibrated by placing a thermometer in a stable reference environment, and then comparing the reading to a standard or reference thermometer. Some instruments that require temperature calibrations are:
- Thermometers
- Thermocouples and Thermistors
- Cool Rooms/Freezers
- Ovens/Furnaces
3) FLOW CALIBRATION
Flow calibration is necessary for industrial and commercial applications that rely on flow rate measurements of a fluid (liquid or gas). Examples of flow rate measurements are volumetric and mass flow rates. Various types of flow meters, such as thermal mass and laminar, measure flow rates for different purposes.
4) ELECTRICAL CALIBRATION
Electrical calibration refers to calibrating instruments that measure electrical parameters. Examples of these include: voltage, current, resistance, inductance, capacitance, time and frequency. Precise devices, such as a precise digital multimeter, can perform calibrations and verify the units under test (UUT). Instruments that require electrical calibration include:
- Oscilloscopes
- Data Loggers
- Electrical Meters
- Frequency Counters
5) MECHANICAL CALIBRATION
Mechanical calibration refers to calibrating instruments that measure mechanical parameters. Examples of these include: mass, volume, density, force, torque, angle, flatness and vibration. Some of the most frequently calibrated mechanical instruments are:
- Scales/Balances
- Load Cells and Force Gauges
- Micrometers and Vernier Calipers
- Torque Wrenches
What Is traceability?
Traceability refers to the capability to chart the history, use, or location of an item by following a documented sequence of events. Simply put, it is a technique to monitor items as they transition through a supply chain. This notion of traceability can be put to use across various things such as food items, electronics, and even calibration!
What Is traceability in calibration?
The capacity to link a measuring device’s readings to a recognized reference standard is known as traceability in calibration. There is assurance that the measurements the instrument makes are correct thanks to this calibration traceability. It is impossible to determine whether an instrument is giving reliable readings without traceability. It also makes comparisons between various labs and instruments possible.
Why is it so important that calibrations are traceable?
A calibrated device is measured against a recognized standard. The traceability procedure guarantees that the standards utilized may be traced back to an international system of units (SI). The traceability of the device’s readings provides assurance of their accuracy and reproducibility. Additionally, traceability makes it possible to compare several calibrations, which yields important details about any potential modifications.
In certain areas, including the manufacture of medical devices, where even a minor inaccuracy can have serious repercussions, traceability in calibration is crucial. By guaranteeing calibration traceability, businesses may steer clear of expensive errors and boost consumer trust in their offerings.
How is traceability achieved in calibration?
Achieving traceability in calibration can be accomplished by utilizing transfer standards, which serve the purpose of calibrating an instrument. These transfer standards undergo calibration against other standards, which in turn may have traceability to national or international standards. Consequently, the process of traceability in calibration follows a hierarchical structure, where each link in the chain contributes to the assurance of accurate calibration results. To attain traceability, it is often necessary to establish and uphold a traceability chain, which documents every step of a product’s progression.
What now?
Calworld Technologies offers traceable calibration certifications within 24 hours of a calibration service. We offer reliable scale calibrating services that guarantee dependable readings and measurements. We may also calibrate other instruments, such as cool rooms, freezers, and ovens, upon request.
Published and written by Calworld Technologies.
