Photo credit: Scott Beale licensed under CC BY-NC-ND 2.0

by Jeanine Botta, MPH, Co-founder, The Quiet Coalition

People living close to construction sites attest to the stress caused by piercing backup beeps intruding in their space. With so many people now working from home due to Covid, the backup sound adds to work stress. Industries and agencies around the world have been using broadband reversing alarms–a quieter, more focused alternative–for decades. Fortunately, some North American counterparts have not only been catching up, but creating and building on models for community engagement around noise.

According to a 2016 article in WorkSafe Magazine, academic research and anecdotal experience have shown that broadband alarms have an important technical advantage over tonal alarms and greater public acceptance. The article traces successful switches from tonal to broadband alarms at the University of Victoria and the resort municipality of Whistler. The university’s facilities management team embarked on broadband retrofitting in 2015 in response to complaints from neighbors who bordered the campus, and the university involved the neighbors, students, and employees throughout the process. Central Services management at the Whistler ski resort and travel destination responded to noise complaints about tonal alarms by testing and implementing broadband alarms beginning in 2010 with great success.

Academic researchers from Ottawa and Montreal looked at worker safety features of backup alarms in 2013 and found evidence that broadband alarms are easier to locate in space than conventional tonal alarms, which is more important with safety than relatively minor differences among the alarms. The researchers cautioned that broadband alarms can alter the effectiveness of hearing protection devices, adding that “careful selection of hearing protection devices is warranted.” Ongoing research in varying contexts finds that tonal alarm sound travels further than broadband sound, which affects those in natural and residential settings. Research and experience show that the sound quality and level of broadband alarms are overwhelmingly better accepted in neighboring communities.

Proliferation of backup alarms on passenger vehicles has complicated the science. It has never been proven that alarm technology used with industrial vehicles should be used with passenger vehicles, and such use might be considered psychological or theatrical. There is evidence that careful driving and use of mirrors, rearview cameras, and detection sensors are sufficient to avoid backup accidents. There is inadequate evidence that passenger car backup alarms serve their intended purpose.

For those wanting to advocate locally for implementing broadband sound technology, accounts of the university’s alarm retrofitting project in the WorkSafe Magazine article and Ottawa’s snow plow retrofitting project, nighttime construction project, and current challenge dealing with supply shortages serve as “how to” guides in understandable lay terminology.

Backup alarm technology is complex. Safety and effectiveness require the ability to understand how tonal and broadband operate in different settings. Misunderstanding the technology-–such as thinking that “louder is safer”-–can result in confusing sounds without any safety enhancement. Some online information about Amazon delivery trucks using broadband technology at high sound levels spreads misinformation, conflating industrial and residential settings. When the sound is that loud, it is being used incorrectly. Amazon and the automakers who manufacture its delivery trucks should engage with acoustical experts and a sampling of community residents to determine the right technology and the right way to use it, although the melodrama might be easily prevented by reducing the volume. Equally important, there are no substitutes for being attentive as a driver, operator, or pedestrian.