A Volumetric Flask is a pear-shaped lab apparatus with a round flat bottom commonly used for dilutions and preparing standard solutions. In 1892, the world's first volumetric flask was invented by Dewar after his name “Dewar Flask”.
The volumetric flask, also known as measuring flask or graduated flask is lightweight, compact and chemical resistant. The flask has a ring graduation marking on its extended neck which stipulates the volume of the liquid when filled up to meniscus. The ridge of the flask has a PE Stopper to prevent spillage and maintain a required temperature for the chemicals.
Classes of a Volumetric Flask
There are two classes in which a volumetric flask is manufactured - Class A and Class B.
The Class A volumetric flasks have the highest level of accuracy with tighter tolerance limits. They have a unique serial number for traceability. The graduation mark on the flask is accurately placed on the flask. The highest accuracy Class A volumetric flasks have a blue colour print for clear glass and white print for amber variants. The Class A flasks are individually calibrated with their certification.
The Class B volumetrics are used for general purpose and are calibrated to a lower level of accuracy. The flasks under Class B have white print on them. Class B flasks lack calibration. This class of volumetric flasks is generally used in schools.
Standards under which the volumetric flask is manufactured
The volumetric flask is manufactured under three standards namely :
ASTM (American Society for Testing and Materials)
ISO (International Organization for Standardization)
USP (United Standard Pharmacopeia).
Glassco is the first ever glassware manufacturing plant in India to produce all the three standards under one roof.
Types of Volumetric Flask:
There are four types of volumetric flasks that meet the ASTM E228 Standards. These are as follows :
Individually Certified Flasks with a Glass Stopper.
Batch Certified Flasks with a Glass Stopper.
Batch Certified Flasks with a Snap Cap.
Individually Certified Flasks with Amber Colour Glass to protect light sensitive solutions.
Sizes of Volumetric Flasks:
The volumetric flasks come in different sizes likewise 2 ml, 5 ml, 10 ml, 20 ml, 25 ml, 40 ml, 50 ml, 100 ml, 150 ml, 250 ml, 500 ml, 1000 ml, 2000 ml and 5000 ml. Glassco manufactures all the sizes of flasks. The small volumetric flasks are used to prepare costly and precious drugs whereas large volumetric flasks are used in pharmaceutical labs for preparing production batches.
Cleaning : Before using a volumetric flask, rinse it with the solvent which is used to prepare the solution. After the completion of the experiment, empty the flask and wash it with warm soapy water. Scrub it with a brush if required. Then rinse it under tap water for 3-4 times. Dry the flask with a clean cotton cloth.
Storage : A volumetric flask should be stored in a dry place in a box to prevent dirt. It is preferred to keep them in a cupboard. Also, the volumetric flasks should be stored with their stoppers so that they are not lost. It is preferred not to store solutions in a volumetric flask as it may corrode and affect the accuracy of the flask.
The use of these volumetric flasks is primarily for measuring accurate volumes of liquid materials for lab experiments. These flasks are of utmost importance when the outcome of an experiment is meant to be meticulous. It measures volumes much more precisely than beakers.
Each volumetric flask has its unique Individual Calibration Certificate stating the standard ratio of volumes in the flask. The stack of measuring flasks is identified by their Batch Calibration Certificate which signifies that the lot has been duly checked and is suitable for sale.
Apart from this, the volumetric flask has a Calibration Certificate from NABL (National Accreditation Board for Testing and Calibration Laboratories) which states the standard weights of the flask. Along with the NABL logo, it contains a unique ULR (Unique Laboratory Report) number which identifies the laboratory where calibration is done.
Glassco has introduced its QR Coded Volumetric Flask which is very useful for the research and development department where calibration certificate is a winning thing. Glassco is the first laboratory equipment manufacturing company from India to pioneer the QR Coded Volumetric Flask worldwide.
The QR Code is permanently screened on the glass which when scanned directs you to the web page of the product providing its certification along with the complete information about the flask. The certificate can be easily printed and saved. At the time of audit, it often becomes difficult for a person to fetch the certificate for each flask. In that case, the QR Code on the volumetric flask makes it easy, simple and handy to download the certificate and verify it.
The second version QR Coded Volumetric Flask was introduced by Glassco itself to make it LIMS compatible. Glassco has collaborated with the Caliber LIMS in order to make it more paperless laboratories using scannable glassware.