Volumetric flasks

Class A flasks have the tighter volume tolerance and suit standards, titrants and validated methods where every dilution must be traceable. Class B flasks have a wider tolerance and are fine for routine dilutions and teaching. The exact tolerance depends on the nominal volume and is set out in ISO 1042. A class A example: the coated volumetric flask, clear glass, 100 ml, NS 14/23, with PE plug, 2 pieces. A class B example: the PP volumetric flask, 100 ml, NS 14/23, with stopper, 2 pieces.

Choose amber (brown) glass for light-sensitive solutions, such as some vitamins, silver nitrate, iodine solutions and many pharmaceutical standards. The brown glass filters much of the light that can break these compounds down while you prepare and use the solution. For long storage, transfer the solution to an amber bottle as well. Examples are the coated class A flask, brown glass, 50 ml, NS 14/23, 2 pieces, and the 100 ml version with NS 14/23, 2 pieces. See all volumetric flasks.

A plastic coating on the outside of the glass holds the pieces together if the flask breaks, so less glass and liquid spread across the bench. That matters with toxic, corrosive or valuable solutions and in teaching labs. The coating does not change the class A accuracy. Before you heat or dry a coated flask, check the temperature limit with us, because it is not stated on these product pages. Examples: the coated flask, class A, 500 ml, NS 19/26, with PE plug, and 1000 ml, NS 24/29. Ask sales@luminixhealth.com.

The stopper must match the joint size on the neck, such as NS 12/21, 14/23, 19/26 or 24/29; the size is in the product title. PE plugs are light, cheap to replace and do not seize. Glass stoppers seal well but can stick, especially with alkaline solutions. Most coated class A flasks here come with a PE plug, for example 250 ml, NS 14/23, 2 pieces and brown glass 100 ml, NS 12/21, 2 pieces. Spare closures are in stoppers, caps and closures.

A volumetric flask is calibrated to contain one volume at a reference temperature, with a single mark on a narrow neck. Class A is the tight tolerance. It is not a storage bottle and it is not for heating. The stopper is part of the calibrated article.

Volumetric glassware is glass that has been calibrated to contain or to deliver one stated volume at a reference temperature. That calibration is the whole point. Class A and class AS have a tighter tolerance than class B. A volumetric flask contains. A pipette and a burette deliver. A measuring cylinder is the coarser reading, used when the volume is not the result. The classes sit under ISO laboratory glassware. The chain back to the unit of volume is the work of the BIPM and of NIST.

This shelf belongs to Volumetric glassware, inside Labware. Luminix Health distributes this range for laboratory use.

The neighbouring shelves are Measuring cylinders, Burettes, Mixing cylinders and Volumetric accessories & certificates. The category above this shelf is Volumetric glassware.

Luminix Health distributes this range from the heart of Europe. We deliver across the EU in two to five days if in stock. Standard delivery is free from €250 excl. VAT. Cold-chain goods and dangerous goods under ADR are never included in that free delivery. The terms are in the Shipping Policy. Send a quote request, contact the team, or read who we are. The full brand index is on shop by brand.

The seven catalogues are Labware, Lab chemicals, Lab instruments, Lab consumables, Chromatography equipment, Lab safety equipment and Life Science & Microbiology. If the article is not on the shelf, request a quote.