Biodegradation testing, respirometer

B.4.2.2 Biodegradation Test Method Standard iSO 14851 (EN14048). Determination of Uitimate Aerobic Biodegradabiiity of Piastic Materiais in an Aqueous Medium—Method by Measuring the Oxygen Demand in a dosed Respirometer... 

Besides the Sturm test another much used aquatic, aerobic biodegradation test is ISO 14851 - Determination of the ultimate aerobic biodegradability of plastic materials in an aqueous medium - Method by measuring the oxygen demand in a closed respirometer. 

Historically, respirometers have been used for wastewater biodegradability evaluation. More recently [52], a mobile on-line respirometer was proposed and tested for monitoring the activated sludge inhibition due to industrial discharges in a sewer network. A derived portable device called a Baroxymeter [53], based on monitoring the respiration of a bacterial culture by pressure measurements and using respiration inhibition as a toxicity alert, was proposed for the rapid detection of the toxicity effect of some toxic substances. 

Determination of the ultimate aerobic biodegradability in soil by measuring the oxygen demand in a respirometer or the amount of carbon dioxide evolved Determination of the degree of disintegration of plastic materials under simulated composting conditions in a laboratory-scale test... 

The second test procedure for EN 13432 standard specifies that a satisfactory rate of biodegradation of the plastic material is under industrial composting conditions of at least 58°C and 50% moisture for 26 weeks, that is, more than 90% of the carbon in the original plastic sample is converted into CO2 as measured by a CO2 respirometer or wet chemistry methods. The details of the test procedures are listed in EN 14046 or ISO 14855 test method. 

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