ISO 11734:1995 specifies a screening method for the evaluation of the ultimate biodegradability of organic compounds in digested sludge at a given concentration by anaerobic microorganisms. Washed digested sludge, containing very low amounts of inorganic carbon, is diluted and incubated at mesophilic condition in sealed vessels for up to about 60 days.

Often both production of methane and carbon dioxide, as well as inorganic carbon dissolved in water or transformed to hydrogen carbonate or carbonate under the conditions of the test are all measured. The percentage of biodegradation is calculated from the total inorganic carbon and the measured or calculated amount of carbon added as test compound. The standard was reviewed and confirmed again in 2017, therefore this version remains current form in 1995.

BPC Blue is a fully automated biodegradability testing system suitable for ISO 11734. It allows for continuous and on-line monitoring of released biogas (CH₄ and CO₂) and is a fully integrated and automated system for sampling, analysing, recording, and generating reports. BPC Blue is the perfect analytical tool that offers standardised measurement procedures, data interpretations and reports.