ISO 5223:1995 – Test Sieves for Cereals
Overview
ISO 5223:1995 is an international standard established by the International Organization for Standardization (ISO) that specifies requirements for test sieves used in the laboratory determination of foreign matter in cereal samples. This standard focuses on sieves designed to separate undesirable substances from cereals and is essential for quality control in agricultural food products. It replaces the earlier 1983 edition with technical revisions and does not apply to sieves used to detect insect infestation in grains.
The standard was developed by ISO Technical Committee 34 on Agricultural Food Products, specifically the Subcommittee for Cereals and Pulses, in cooperation with the International Association for Cereal Science and Technology (ICC). It provides clear specifications for dimensions, materials, and construction of test sieves typically employed in cereal testing laboratories.
Key Topics
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Scope and Application
- Test sieves for laboratory use in identifying foreign matter in cereal samples.
- Covers sieves with specific nominal aperture sizes, including long rounded apertures and round apertures.
- Excludes use for insect infestation detection.
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Sieve Types and Sizes
- Long rounded apertures ranging from 1.00 mm × 20.0 mm up to 3.55 mm × 20.0 mm.
- Round apertures with a nominal diameter of 4.50 mm primarily for separating broken maize grains.
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Material and Construction
- Sieves must be made entirely of metal.
- The sieving medium can be stainless steel, plated mild steel, or other suitable materials.
- Apertures must be cleanly formed and securely attached to the frame to prevent detachment.
- Frames are circular with a nominal internal diameter of 200 mm ± 1 mm, designed for smooth assembly with lids and receivers.
- Frame depth ranges between 25 mm and 55 mm, with shallower depths (25-35 mm) recommended for manual onsite operations.
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Aperture Arrangement and Quality
- Long rounded apertures arranged in linear rows with specific pitch and tolerances.
- Round apertures arranged in staggered rows to ensure efficient separation.
- Aperture sizes must be verified for dimensional accuracy using magnification techniques.
- Aperture pitch and plate thickness also subjected to strict quality checks.
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Markings and Identification
- Each sieve must have a clear identification label detailing the ISO reference, nominal aperture size, manufacturer/supplier name, and sieve number.
- Officially tested sieves carry identifiable certification marks.
Applications
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Quality Control in Grain Processing
Test sieves conforming to ISO 5223 are critical tools for cereal laboratories assessing the purity and quality of grain lots by mechanically separating foreign matter, such as shriveled kernels or broken grains.
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Cereal Trade and Commercial Inspection
The sieves enable consistent evaluation of grain batches, supporting accurate commercial valuation and compliance with trade agreements.
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Research and Development
Researchers working on cereal quality and processing utilize these sieves for precise sample preparation and analysis.
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Calibration and Standardization
Ensures uniformity in sieve characteristics, enabling reliable and reproducible test results across different laboratories and geographies.
Related Standards
- ISO 2395:1990 – Vocabulary for test sieves and test sieving terminology, providing standardized definitions to support ISO 5223.
- ISO 3310-2:1990 – Specifies technical requirements and testing methods for test sieves with perforated metal plates, referenced for round aperture sieves in ISO 5223.
- ISO 683-13:1986 – Details material properties for stainless and alloy steels appropriate for manufacturing sieve plates.
Keywords: ISO 5223, test sieves for cereals, cereal quality control, laboratory sieves, sieve aperture sizes, agricultural food standards, foreign matter determination, grain testing equipment, stainless steel sieves, sieve dimensional specifications, cereal sample analysis, ISO standards for test sieves.
