PRODUCTION AND DISTRIBUTION OF CHEMICAL REFERENCE MATERIALS

The preceding chapters detail the extensive need for reference maferi-als in the ocean sciences. This chapter focuses on what is required to produce new reference materials as well as how to encourage the use of those that already exist. 

Reference materials must fulfill certain rigorous criteria before they are accepted and found useful by the analytical community. The following conditions are prerequisites for preparing reference materials that are mutually acceptable to organizations around the world  

Homogeneity. Homogeneity assures that the analysis of all subsamples of the reference material taken for measurement will produce the same analytical result within the stated measurement uncertainty. This is particularly important in the case of certified reference materials. Reference material producers therefore must specify the minimum amount of sample for which homogeneity has been measured and is valid. Finally, the ease of re-homogenizing the material after packaging must be taken into consideration. 

Stability. Producers must state the length of the reference material s useable life, since they can be sensitive to light, humidity, microbial activity, temperature, time, etc. Long-term testing is required to validate the stability of a material under a variety of storage and transport conditions. 

Similarity to the real sample. To produce meaningful analytical results, the reference material should mimic as closely as possible the matrix of the test sample. 

---

Inaccurate laboratory measurements can mean wrong medical diagnosis and treatment, lost production time, wasted energy and materials, manufacturing rejects, and product liability. The U.S. National Institute of Standards and Technology and national standards laboratories around the world distribute Standard Reference Materials, such as metals, chemicals, rubber, plastics, engineering materials, radioactive substances, and environmental and clinical standards that can be used to test the accuracy of analytical procedures.1... 

The development of ne v catalysts during the last two decades has introduced more environmentally accepted processes into the production of commodities. The industrial solid catalysts that once played a major role in bulk chemicals manufacture are nowadays distributed among the industrial sectors so that about 25% of produced catalysts are used in the chemical industry, 40% in the petroleum industry, 30% in environmental protection, and 5% in the production of pharmaceuticals. Environmental catalysis accounts for (i) waste minimization by providing alternative catalytic synthesis of important compounds without the formation of environmentally unacceptable by-products, and (ii) emission reduction by decomposing environmentally unacceptable compounds by using catalysts. Waste minimization is linked with the reaction(s) selectivity and therefore a proper choice of catalyst plays a decisive role. Emission reduction usually refers to end-of-the-pipe treatment processes where the selectivity of catalyst, if used, is not an important issue. Because it is almost impossible to transform the raw materials into the desired products without any by-product(s), one must take account of the necessity of providing a production process with an end-of-the-pipe treatment unit. Only then can... 

---