ISO 24255:2025

Overview

ISO 24255:2025 specifies quality characteristics and test requirements for the essential oil of clary sage (Salvia sclarea L.) - two French commercial types: “prewilted” French type and “chopped” French type. The standard is intended to facilitate consistent quality assessment for producers, testing laboratories, traders and regulatory bodies involved in essential oils, perfumery and aromatherapy.

Key topics and technical requirements

• Identification & general characteristics
  • Appearance: liquid (colourless to brownish yellow, usually pale yellow).
  • Odour: sweet, herbal, floral, amber-like.
• Physical constants
  • Relative density at 20 °C (d20):
    • Prewilted: 0.895–0.908
    • Chopped: 0.890–0.902 (ISO 279)
  • Refractive index at 20 °C: 1.456–1.466 (ISO 280)
  • Optical rotation at 20 °C:
    • Prewilted: −24° to −10°
    • Chopped: −20° to −7° (ISO 592)
  • Miscibility in ethanol (80 % v/v at 20 °C): requirement for obtaining a clear solution using up to three volumes of 80 % ethanol per one volume of oil (ISO 875).
• Chromatographic profile (required)
  • Gas chromatography per ISO 11024 series: identify and quantify characteristic components. Representative component ranges (integrator %):
    • Linalyl acetate: Prewilted 62–78 %, Chopped 54–71 %
    • Linalool: Prewilted 6.5–15 %, Chopped 13–24 %
    • α-Terpineol, Germacrene D, Sclareol: specified minimum/maximum ranges (see standard Table 2).
  • This chromatographic fingerprint is mandatory to confirm type and origin characteristics.
• Flash point
  • Informative mean value: 84 °C (Pensky‑Martens method noted in Annex B).
• Sampling, packaging and labelling
  • Sampling in accordance with ISO 212; minimum test sample 50 ml.
  • Packaging, labelling and storage per ISO 210 and ISO 211.

Applications and who uses this standard

• Essential oil producers: define product specifications and batch release criteria.
• Analytical laboratories / QC labs: perform GC profiling and physical tests for conformity.
• Perfumers & cosmetic formulators: verify composition and olfactory consistency (linalyl acetate/linalool balance).
• Importers, traders and regulators: ensure product authenticity, safety (flash point information) and correct labelling.
• Transport and insurance: use flash point and packaging guidance for safe handling.

Related standards

• ISO 11024 (chromatographic profiles), ISO 279, ISO 280, ISO 592, ISO 875, ISO 212, ISO 210, ISO 211 - all cited within ISO 24255:2025 for test methods and practical implementation.

Keywords: ISO 24255:2025, essential oil of clary sage, Salvia sclarea, prewilted French type, chopped French type, chromatographic profile, linalyl acetate, linalool, quality assessment, essential oil standards.