Author(s): Laroche Chantal, Giguère Christian, Vaillancourt Véronique, Marleau Claudia, Cadieux Marie-France, Girard-Laprise Karina, Bibeau Manuelle, Gula Emily, Carroll Véronique, Nélisse Hugues
Despite the mandatory use of reverse alarms on heavy vehicles in many workplaces, accidents still occur. Among other factors potentially contributing to the occurrence of such accidents, reverse alarms can be difficult to localize in space, leading to errors in adequately identifying the source of danger. Previous studies have shown that traditional reverse alarms (“beep-beep”) are more difficult to localize in space than broadband alarms (“pschtt-pschtt”). In addition, personal safety equipment such as hearing protection devices, often required in noisy workplaces where reverse alarms are used, may potentially further impair localization. This set of studies explored the effect of hearing protection devices on the ability of normal-hearing individuals to localize reverse alarms (tonal and broadband) in background noise, while performing a task. Passive hearing protection (earplugs, earmuffs and double protection) was used in the first study, while the second study focused on level-dependent (sound restoring) devices. Standing in the middle of an array of 8 loudspeakers covering 360°, participants were asked to identify the loudspeaker thought to have emitted a single cycle of the alarm while performing a task on a tablet computer mounted on a tripod directly in front. Consistent with previous findings, the broadband alarm was easier to localize than the tonal alarm. Results also show that passive hearing protection can have a significant impact on sound localization (earmuffs generally more so than earplugs), and that double hearing protection should be avoided in workplaces where good sound localization abilities are required. Further, level-dependent hearing protection doesn’t seem to restore sound localization abilities.
Name: Ms Chantal Laroche