Sampling and Physical Description of Amphetamines

What advantage is there in using a random-number table or generator to determine which of the samples should be analysed  

The advantage of this is that it removes any bias which might be imparted by the operator in sample choice. 

Once the samples to be analysed have been identified, physical descriptions, homogenization and sampling, presumptive testing, TEC and confirmatory testing should be undertaken. 

What is the advantage of recording the baiiistic features of tabietted drug units  

Having recorded all of the physical data, the items to be examined chemically should be chosen. At the time of writing, there is no agreed best-practice protocol for undertaking this and the analyst should work within the requirements of the judicial system in which he/she is operating. The theory applied to powdered amphetamines can be equally applied to amphetamine tablets. The latter should be sampled and presumptive tests, TLC and confirmatory tests then carried out. 

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