Siren fatigue and the danger of being tuned out
Last weekend this headline, 'Did Global Warming Destroy My Hometown?' from the POPSCI blog caught my attention, and indeed it proved to be a really interesting and personal read about the effects of the devastating tornado that descended on Jopin, MO last spring. In fact to me, the piece was interesting not for its ability to answer the question expressed in the title, (I suppose the answer is really 'Maybe' or 'We don't know'), but rather it's examination of what happened in Joplin before, during, and after the tornado tore through town.
The Joplin tornado of May 22, 2011 would eventually be categorized as a EF5 storm, the strongest and most dangerous classification, result in 161 fatalities, 1,150 injuries, and cause over $2B in damages. Of course none of this, the seriousness of such a massive and deadly storm, and the impact and devastation it would render, could have been known in advance by the people of Joplin that day. While the full nature of the fury could not be known in advance, there was at least some indication that something bad was about to happen in Joplin. By most accounts, the series of steps conducted by the various national and local authorities responsible for weather forecasting and public safety resulted in the sounding of the tornado warning siren in Joplin about 30 minutes prior to the tornado's arrival functioned as designed and expected. But despite the advance warning, and other precautionary measures taken by an area well accustomed to potentially dangerous weather, significant fatalities and injuries still occurred.
One reason, and probably the primary reason, was of course the sheer size and destructiveness of the May 22 tornado. As an EF5 storm, packing 200+ MPH winds, there is little that even the most soundly built structures and safty shelters could do to withstand that kind of assault. But in addition to the fury of the massive storm, some reports, including the above-referenced POPSCI piece call attention to the idea of something called siren fatigue, the tendency for people in high-risk tornado areas to downplay the significance of, and perhaps to fail to take appropriate safety precautions when the tornado siren is called due to the high volume of tornado false alarms that have been previously sounded.
From the POPSCI piece:
But the biggest concern was what the investigators called siren fatigue.
Like many other towns, Joplin’s policy is to sound a three-minute siren when a storm with winds stronger than 75 mph is approaching town, regardless of whether an NWS agency has issued a watch or warning. So at 5:11 on May 22, after local emergency managers were informed that a funnel cloud had been sighted over southeast Kansas, the city sounded a siren. But warning too early can be dangerous, particularly in a siren-jaded area. The NWS study describes one man’s confused, lackadaisical response: “(1) Heard first sirens at 5:11 p.m. CDT (estimated 30–35 minutes before tornado hit). (2) Went to the TV and heard NWS warning from TV override that indicated tornado near airport drive seven miles north (polygon #30) of his location. (3) Went on porch with family and had a cigar.”
Twenty-seven minutes later, the man heard another set of sirens. At this point, he “thought something wasn’t right,” so he went back inside and turned on the TV, where meteorologists were still warning that the threat was north of town. Then his wife yelled “Basement!” The report concludes this summary of events thusly: “Tornado hit as they reached the top of the basement stairs, destroying their home.”
Wow. Some gripping, riveting stuff. The kind of thing that should make most of us glad we don't have those types of life of death kinds of calls to make. Sounding the alarms and sirens when there is the just the chance of a dangerous storm, most of which either do not materialize or are relatively minor, has the tendency over time of dulling the siren's effectiveness, and introducing a kind of complacency in the minds of some residents. While the problem is fairly easily identified, the right solution to combat siren fatigue is less clear. Different signal sounds for different local conditions is one option, better and more accurate forecasting is another, but eventually when faced with the decision of whether or not to sound the sirens, the need for erroring on the side of safety usually prevails.
It's just a couple of months until the start of the active tornado season in many parts of the US, and no doubt once the storms start forming in the Midwest and South the siren fatigue discussion will be continued. The larger point in all of this, and why I thought it relevant to write about on a site (mostly) about the workplace - if people can be conditioned to tune out messages meant to quite possibly save their lives, then it is about 100% certain that at least some of the important messages you are sending to your colleagues, your staff, your friends - whatever, have a good chance of being tuned out as well.
Even if the message you need to convey is an important one, like a tornado warning siren, if it keeps coming in the same manner, at the same time, delivered over and over again, eventually it becomes just another piece of noise in the stream. Fortunately for most of us, the consequence of our messages being tuned out probably isn't terribly significant in the big picture. Most people will carry on just fine by ignoring our message.
Fortunately, I suppose, the danger is probably more to our own careers.