What is the technical difference between 'aperture' and 'mesh'?

Aperture is the clear dimension between adjacent wires (the actual opening size), whereas mesh conventionally refers to the number of openings per linear unit (like an inch).

What does 'oversize' mean in test sieving terminology?

Oversize refers to the portion of the material charge that does not pass through the apertures and is retained on a specific testing sieve.

What is meant by the 'charge'?

The charge is the specified test sample or quantity of material placed on a test sieve for analysis.

IS 5421

: 1981

Glossary of terms relating to testing sieves and test sieving

CurrentSpecializedTerminologyMaterials Science · Sieves, Sieving and Other Sizing Methods

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This standard provides a glossary of standardized terms relating to testing sieves and test sieving procedures. It ensures uniformity in terminology across different disciplines performing particle size analysis, material grading, and quality control of granular materials.

Glossary of terms relating to testing sieves and test sieving

Practical Notes

Use this standard to resolve technical ambiguities in lab reports, distinguishing clearly between terms like 'mesh', 'aperture', and 'wire diameter'.

Modern engineering practices prefer specifying sieve sizes by 'aperture size' (in mm or microns) rather than 'mesh number', to prevent confusion caused by varying wire thicknesses.