ISO 21338:2010 specifies the kinetic direct‑contact method for determining the inhibitory effect of suspensions of sediment and other solid samples, and also for problematic turbid or coloured aqueous samples on the light emission of the marine bacterium Vibrio fischeri (NRRL B‑11177).

This method is applicable to: a) sediment samples and water suspensions of sediments (fresh water, brackish, and seawater sediments); b) effluents (especially turbid and coloured); c) aqueous extracts (e.g. leachates, eluates, elutriates) of soil, solid waste, and other solid material (especially turbid and coloured).