BS 4845-1 specifies procedures for the sampling of consignments of domestic coke of up to 63 mm nominal upper size in the range 50–5 000 kg, either in bulk or in bags.
BS 4845-1 on methods for sampling manufactured domestic solid smokeless fuels consignments is useful for:
The principles of incremental sampling and the precision which is obtained in practice are discussed in detail in BS 1017-2. In preparing that standard the procedures evolved were designed to provide the required precision in sampling for the determination of moisture. The same principle has been adopted in considering the procedures of BS 4845-1.
BS 4845-1 provides guidance for preparing samples, partial drying of the sample and overall carrying out sampling procedure for domestic solid smokeless fuels consignments with precision.
Bearing in mind the fact that the precision obtainable from a sample is dependent upon the number of increments taken, and that the mass of an increment must be determined by reference to the size of the coke to be sampled, it follows that for a given precision the mass of sample must not be less than a minimum related to the nominal upper size of the coke, which in cases covered by BS 4845-1 will not exceed 63 mm.
In order to obtain a representative sample from a quantity of coke in bulk, it will be necessary in every case to carry out incremental sampling of the whole quantity.
Since it is not practicable to apply this principle when the coke is contained in a number of bags, the recommended procedure under these circumstances involves the selection of the requisite number of complete bags, the contents of which are mixed and the required mass extracted by increments.