The Importance of Volumetric Glassware Calibration

The validity of scientific testing and the analysis of chemical products can only be confirmed if the measuring equipment is reliable. All types of labs use volumetric glassware for a range of different practices. However, much like all other laboratory equipment, calibration is needed to ensure you’re getting accurate results every time.

National Weighing and Instruments has recently become accredited by the National Association of Testing Authorities (NATA) to undertake volumetric glassware calibration services. So, to mark the occasion, here’s some information about the importance of volumetric glassware calibration.

What are the different types of laboratory glassware?

Volumetric glassware basically refers to all types of vessels used in laboratories for testing and storage. These include:

• Pipettes
• Burettes
• Volumetric Flasks
• Cylinders

Depending on their intended use, glassware is categorised in terms of accuracy level. Higher grade glassware is known as Class A, while the lower grade is referred to as Class B. Glassware used in chemical applications must be able to deliver a high level of precision and accuracy. If you’ve wondered why laboratories use glassware for such precision-reliant activities, it’s because glass provides better dimensional stability, and is also resistant to most chemical compositions. However, they are not immune to degradation.

How does volumetric glassware get damaged?

While glass is resistant to most chemicals, erosion can still occur over time. Hydrochloric acid, for example, is one chemical which can cause glassware to erode. Highly concentrated alkaline solutions and concentrated phosphoric acid can also cause erosion when used at high temperatures. Erosion levels in laboratory glass are very low, however over time, the depth of erosion increases to a point that accuracy is diminished.

So, while the materials put into your volumetric glassware can have an effect, so too can cleaning. Most laboratory glassware is cleaned in a dishwashing device, using alkaline detergents. If you use harsher cleaning methods such as sonic baths, erosion can be accelerated even more.

Naturally, if glassware erodes over time, the measurements will become inaccurate. Measurement markings on the outside of the glassware won’t be correct, because the vessel will now be able to hold more liquid.

What is laboratory glassware calibration?

Volumetric glassware calibration is essential to ensure accurate results in all laboratory settings. Calibration takes place before glassware is put into circulation for use, and there are also recommended timeframes to conduct calibration on older glassware.

The NATA general equipment table recommends calibration take place:

• On Initial commissioning
• Every 10 years for Borosilicate glassware
• Every 5 years for Soda-Lime glassware

It should be noted, however, that the calibration timeframe may need to be reduced if glassware is used regularly with corrosive substances, or used at high temperatures.

Why is NATA endorsement important?

Essentially, any testing facility can claim they conduct flawless calibration of volumetric glassware. However, NATA endorsement ensures that the testing facility’s equipment processes are up to the highest standard. At National Weighing and Instruments, for example, we calibrate laboratory glassware against International Standard ISO 1042 for accuracy. This is common among most testing facilities.

The benefit of NATA endorsement, though, means our calibration services are also ISO 17025 Compliant. ISO 17025 confirms the highest standard quality management system for testing and calibration laboratories.

Choose National Weighing and Instruments

Essentially, if you want peace of mind that your volumetric glassware is calibrated to the highest standard, choose a NATA accredited testing facility such as National Weighing and Instruments. We perform volumetric glassware calibration from 1ml to 5L, and we’re one of few laboratories in Australia with this accreditation.