ISO 10249:1996

Overview

ISO 10249:1996 specifies procedures for the preliminary visual examination and preparation of samples of fluid fertilizers for physical testing. It covers inspection of single laboratory samples as received and the blending/reduction of multiple increments representative of a consignment or bulk delivery. The standard emphasizes rapid handling because fluid fertilizers are sensitive to time and temperature.

Key topics and requirements

• Preliminary visual examination
  • Record ullage (air space) as a percentage of container capacity.
  • Note surface films, incrustations, separation of phases, clarity, colour, temperature, and consistency (free-flowing or gelled).
  • Identify and record any extraneous matter; remove carefully.
• Mixing and homogenization
  • Different procedures for solutions and suspensions:
    • Solutions: shake or stir thoroughly unless the sample is for physical assessment.
    • Suspensions: minimize disturbance during initial inspection; mix thoroughly unless hard-dry settling or gelation prevents re-incorporation.
  • For samples with hard settling (but not hard-dry), transfer fluid to a clean container, re-incorporate sediment with spatula, and pour between containers to homogenize.
  • Avoid entrainment of air; samples must be free from air-bubbles before testing.
• Limitations
  • Samples that have gelled or show hard-dry settling may not be suitable for testing because they cannot be effectively re-homogenized.
• Blending and reduction
  • Aggregate multiple increments by thoroughly mixing each and combining into a clean transparent container; when reduced samples are taken allow at least 5% ullage in final containers.
  • Protect photosensitive products from light.
• Labeling and reporting
  • Labels must include product name, manufacturer/blender, dates (manufacture/blending and sampling), consignor, consignment details, sampling location, sampler name, batch/reference numbers, and a reference to ISO 10249.
  • Sample test reports must document description, reference to the standard, appearance/clarity, incrustation/settling observations, mixing procedures used, and examiner/date.

Applications and users

ISO 10249 is used by:

• Quality control and laboratory personnel performing physical testing of fluid fertilizers
• Fertilizer manufacturers and blenders establishing sampling and sample-preparation protocols
• Regulatory authorities and inspectors assessing consignment conformity
• Third-party testing laboratories accepting, preparing, and documenting samples

Practical benefits include consistent sample handling, defensible test results, reduced variability from improper homogenization, and clearer traceability in quality and compliance reporting.

Related standards

• ISO 8358:1991 - Solid fertilizers - Preparation of samples for chemical and physical analysis (complements ISO 10249)
• ISO 5306:1983 - Fertilizers - Presentation of sampling reports (referenced for reporting)