Stringent quality criteria

Biodegradable plastic products must meet stringent quality criteria if they are to be composted. Dedicated standards and certification schemes/tests have been established for verifying the compostability of plastic products. 

Saltelli, A., Funtowicz, S. When all models are wrong More stringent quality criteria are needed for models used at the science-policy interface. Issues in Science and Technology Winter, 79-85 (2014)... 

MSQ = most stringent water quality criterion (guideline) for substance i... 

The accuracy of measurements is the quality criterion most difficult to determine (see Chapter 1). However meticulously prepared the standards might be, the voliunetric loops prepared and calibrated, and however carefully other easily identified sources of systematic errors are taken into accoimt, there are no direct measurements or calculations of the analytical accmacy. Intercomparison with other laboratories, exchange of standard mixtures, etc., give some indication of the correct concentration range. In international work, the demands are about twice the reproducibility limits, Le., within 2-5 %. Such demands necessitate the exchange of highly reliable standard mixtures which are difficult to prepare and expensive to purchase. For halocarbon studies others than tracer work and data collection for international data inventories the demands are less stringent. 

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