LEGAL METROLOGY ASPECTS OF SOUND AND VIBRATION REGULATIONS. HOW DO WE ENSURE WE GET IT RIGHT

摘要

The concept of the weights and measures inspector going around the market with his one-pint pot and a one-pound weight is an established fact of history. With increasing regulation, and ensuing enforcement legal metrology has been borne. The objective is to ensure that the measurements used in association with litigation are of known, and acceptable, uncertainty. Instrumentation standards now not only specify what an instrument should do, they also detail the independent tests necessary to prove they conform. In addition, there is a recommended subset of these tests that should be carried out periodically to ensure that the instrument continues to meet the specification throughout its working life. These new sub-sections or annexes to the standard define what is known as pattern evaluation (PE) and this is the manufacturer's responsibility to complete. These tests are normally carried out by a national metrology institute but can be performed by other independent accredited laboratories. The sub-set of the PE tests are known as Periodic Verification (PE), and they are an extended form of what many people know as annual calibration of their instrument; and again, the testing needs to be carried out by a suitably accredited calibration laboratory. So, if the instrument has undergone the PE examination as well as the PV testing there is a clear route to confirming that the instrument fully meets the requirement of the standard; hence it can have a legally recognized certificate of Calibration and Conformance.