Glossary R

The Environmental Glossary. Letter R +++ 'Range', 'Relative percent difference (RPD)', 'Recycling'

A R rating curve is a drawn curve showing the relation between gage height and Discharge of a stream at a given gaging station.

Radon (Rn) is a cancer-causing radioactive gas found in many communities' ground water. Radon is a colorless, odorless, naturally occurring, radioactive, inert, gaseous element formed by radioactive decay of radium (Ra) atoms.

A Random Error is an unplanned deviation of an observed value from the true value that occurs produced by unpredictable and unknown sources of variation, e.g., due to fluctuations in conditions such as temperature, mechanical vibrations, reading error, etc.; also known as experimental error.

A Random Sample is a subsection of a population selected in such a way that each unit of the population has the same chance of being selected.

German: Bereich
A Range is the difference between the maximum and minimum values of a set of values. When the number

A Ranked Set Sampling is a specimen site-selection process wherein expert judgment or an auxiliary measurement method is used, in combination with simple random specimen collection, to determine which locations in the field should be selected.

The Raw Data are all the documentation generated during sampling and analysis which includes, but is not limited to, field notes, hardcopies of electronic data, disks, untabulated sample results, QC sample results, printouts of chromatograms, instrument outputs, and handwritten notes.

A Readiness Review is a systematic, documented assessment of the preparedness for the start-up or continued use of a facility, process, or activity typically conducted prior to initiation of a major phase of work.

A Record is a completed document that provides evidence of an item or process, e.g., photographs, drawings, magnetic tape, and other data recording media.

A Reference Method is a procedure or process which is considered a standardized or commonly accepted and to which another procedure or process is compared.