The latest update to the ASTM E544 standard has been published as ASTM E544-24, effective from 6 September 2024. This update revises the previous ASTM E544-18 standard, which was issued in 2018. The original ASTM E544 standard was first introduced in 1999.
ASTM E544-24 provides essential guidelines for referencing the odour intensities of odorants within the suprathreshold region, using the ASTM Odour Intensity Referencing Scale. The updated standard continues to outline two primary methods for this purpose:

