On the importance of measurement uncertainty in conformity assessment of acoustic quantities

In the various fields of applied acoustics, a common problem is the assessment of the conformity of measured values of acoustic quantities to limit values. This problem becomes par-ticularly critical when considering that measured values are always affected by a measurement uncertainty, while national regulations generally set absolute limit values, ignoring the uncertainty. From this point of view, the solution is not trivial and calls for the adoption of appropriate decision rules. Building on the background of ISO IEC GUIDE 98-4, this work presents the problem in an easy-to-understand form, review the basic decision rules and pro-poses a simple methodology to operate in a consistent way. Some examples taken from the everyday work of acousticians are discussed.