Noise labeling for consumer products

Abstract

Currently, ISO 4871-1996 (Acoustics–Declaration and verification of noise emission values of machinery and equipment) uses A-weighted or spectral sound power levels as metrics of choice for noise labeling. Also included is a measure of the likely variations in levels that result from machine to machine variability, measurement to measurement variability, and site to site variability. This labeling scheme is adequate to label machinery for use in commercial or industrial settings. Here, plant engineers or audiologists, etc., can readily interpret and use data. But a two-number label using the sound power level in decibels is not optimum for conveying information to the consumer. This paper suggests an alternate form for the data. Sound power is still the physical quantity measured, and, as suggested by others, a one-number system is used. The statistical variation is included by reporting the value that will not be exceeded in 19 out of 20 measurements. But the metric reported is one that is roughly proportional to judgments of loudness, and, as such, should provide greater meaning and clarity to the user. Hopefully, with comprehensible noise labeling, the consumer will be able to include noise in his/her choice of products.