# Commission Directive 2004/73/EC of 29 April 2004 adapting to technical progress for the twenty-ninth time Council Directive 67/548/EEC on the approximation of the laws, regulations and administrative provisions relating to the classification, packaging and labelling of dangerous substances (Text with EEA relevance), Division 1.7.2.2: Measurement of glucose-induced respiration rates

Extent: E+W+S+N.I.

The glucose-induced respiration rate in each treated and control replicate is determined at each sampling time. The soil samples are mixed with a sufficient amount of glucose to elicit an immediate maximum respiratory response. The amount of glucose needed to elicit a maximum respiratory response from a given soil can be determined in a preliminary test using a series of concentrations of glucose (14). However, for sandy soils with 0.5-1.5% organic carbon, 2000 mg to 4000 mg glucose per kg dry weight soil is usually sufficient. The glucose can be ground to a powder with clean quartz sand (10 g sand/kg dry weight soil) and homogeneously mixed with the soil.
The glucose amended soil samples are incubated in a suitable apparatus for measurement of respiration rates either continuously, every hour, or every two hours (see section 1.6.1) at 20 ± 2 oC. The carbon dioxide released or the oxygen consumed is measured for 12 consecutive hours and measurements should start as soon as possible, i.e. within 1 to 2 hours after glucose supplement. The total quantities of carbon dioxide released or oxygen consumed during the 12 hours are measured and mean respiration rates are determined.

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Source: https://www.legislation.gov.uk/eudr/2004/73/annex/2I/division/C.22/division/1/division/1.7/division/1.7.2/division/1.7.2.2 (the official version)
Page: https://openlegislation.uk/eu-directive-2004-73/annex-2I/division-C.22/division-1/division-1.7/division-1.7.2/division-1.7.2.2
Contains public sector information licensed under the Open Government Licence v3.0. Source: legislation.gov.uk, The National Archives.