Sampling Flashcards
A sample taken at a particular time within an interval of a few seconds to a minute
Grab sample
A sample resulting from a sampling plan that can be expected to adequately reflect the properties of interest of the parent population
Representative sample
A sample consisting of portions obtained from identified subparts (strata) of the parent population. Within each stratum, the samples are taken randomly
Stratified sample
A sample that is deliberately chosen by using a sampling plan that screens out materials with certain characteristics and/or selects only material with other relevant
characteristics
Selective sample
A sample taken, prepared, and stored in an agreed upon manner for the purpose of settling dispute
Umpire or referee or reserve sample
Sample taken in a series of steps with the sampling portions being selected from the larger or greater number of portions of the previous step
Multistage sample
Multiple (or two) samples taken under comparable conditions. This selection may be accomplished by taking units adjacent in time or space.
Replicate (duplicate) sample
Units, increments, or samples taken one at a time or in successive predetermined groups, until the cumulative result of their measurements assessed against
predetermined limits, permits a decision to accept or reject the population or to continue sampling
Sequential sample
A sample chosen on the basis of accessibility, expediency, cost, efficiency, or other reason not directly concerned with sampling parameters
Convenience sample
A sample obtained by removing specific fractions by separation or selection techniques (heavy liquid, magnetic, sieving, etc.), analyzing the fractions separately, and
combining the results mathematically.
Combined sample
A sample or a known fraction of the parent population in which the analyte has been isolated or (usually) concentrated before being submitted to the laboratory
Modified sample
The selection, removal, and preparation of the test (analytical) portions from the laboratory sample.
In-laboratory Processing
The combining of components, particles, or layers into a more homogeneous state.
Mixing
The reduction in size of a granular or powdered sample by forming a conical heap which is spread out into a circular, flat cake. The
Coning and quartering
The separation of a free-flowing sample into (usually) equal parts by means of mechanical device composed of divider chutes.
Riffling
The mechanical reduction of the particle size of a sample by attrition (friction), impact, or cutting.
Milling or grinding
An individual portion of material collected by a single operation of a sampling device.
Increment
The collection of one or more increments or units initially taken from a population.
Primary sample
A representative part of the primary (composite or gross) sample obtained by a division and reduction process
Reduced sample
Portion of the sample obtained by selection or division
Subsample
The sample or subsample sent to or received by the laboratory
Laboratory sample
The quantity of material, of proper size for measurement of the concentration or other property of interest, removed from the test sample.
Test portion/analytical portions
The test solution that has been subjected to reaction or separation procedures prior to measurement of some property.
Treated solution
The sample, prepared from the laboratory sample, from which test portions are removed for testing or for analysis
Test sample/analytical sample
