Escalators are pretty hazardous too – the husband of a former boss of mine worked on escalators. When I asked him what about escalators might surprise people, he told me he wouldn’t use them; he’s seen too many injuries and heard of too many deaths.
We can all think of stories in the news over the last decade or so – toxic paint on toys, airbags deploying with too much force, kids exposed to germs on their stuffed animals, and more than 60,000 toilet-related injuries in the US every year. But all of these are small beans compared to the most significant – driving – which kills over 30,000 people annually – year after year after year – and injures more than 2 million. When family, friends, and colleagues ask me about the risks of living in New York City, I point out that, by taking mass transit instead of driving, my net risk profile is far better than when I lived in small towns and cities upstate.
Are my friends and family who drive everyday idiots? What about all those fishermen? Or the clueless people riding escalators, golfers (don’t ask), parents who let their kids play with toys, and all these other dangers that lurk beneath the placid surface of our society? Why do we continue to think that all of these things are safe when, in fact, they injure or kill on a regular basis?
Risk and Safety
Part of the answer is that we’re using two different terms – “risk” and “safety” as though they are different sides of the same coin. They’re not; “safe” is a qualitative term while “risk” – as used by scientists and engineers, anyhow, is quantitative.
After the Fukushima reactor accident, I was asked to determine the lowest-risk option for New York City residents if there were a comparable reactor accident at the Indian Point reactor plant, about 30 miles or so north of NYC. The National Highway Traffic Safety Administration reports 1.37 traffic deaths for every 100 million vehicle miles driven. It turns out that evacuating the city was the worst option – the number of expected deaths from driving 8.5 million New Yorkers 100 miles to “safety” was greater than the expected number of cancer fatalities from sheltering in place and waiting for the short-lived iodine isotopes to decay away.
The same risk can seem safe to me and unsafe to you
Fleeing a reactor meltdown can carry with it a greater risk than absorbing a low dose of radiation. And this is what I mean when I say that “risk” is a quantitative term – I can calculate the risk using death and injury statistics. “Safe” is how I feel about those risks, and my feelings are likely to be different than yours in several areas.
Say I’m talking to a friend who’s worried about something that has a risk of killing one person in a million every year. My view of the matter is that it’s far less risky than driving, and the odds are very much against this risk affecting me in the slightest. But my friend realizes that 8-9 New Yorkers will die of this risk annually – and to him, this might be unacceptable.
The problem is that most people hearing the term “low-risk” focus on the word “risk,” which they equate with “danger,” and ignore the word “low.” When I express risk in the way I’ve been trained, as a scientist, say those 1.37 deaths per 100 million vehicle miles driven – I’m concentrating on the fact that 100 million miles is a lot of driving. Most members of the public concentrate on the 1.37 deaths. Again, two people hearing the same factual information come to wildly different conclusions due to how they process those facts.
And then there’s something else – as a scientist, I’m reluctant to tell anyone that anything (or any activity) has zero risks; even something that happens only one time in a billion is still a risk, albeit very small. My tendency to refer to that one in a billion chance as “low-risk” is scant comfort to those who focus on “risk” rather than “low.”
But here’s the thing – most people, hearing me say that an activity is “low risk” while another person confidently says “people are going to die” will tend to place more faith in the absolute statement, even if it’s unsupported by any solid facts and even if the person uttering it is unqualified to speak authoritatively on the matter. My inclination in such cases is to give less credence to the person speaking in absolutes – I’m more willing to believe the person who speaks in probabilities because they’re more likely to actually know what they’re talking about with something complex like radiation health effects.
This confusion about risk and safety continues to be apparent as physicians, politicians, public health officials, and our neighbors debate the various aspects of COVID-19. You can see the same dichotomy in how people use the words “risk” and “safe.” While public health officials, physicians, and scientists talk about risks – the low risk posed by vaccination, the moderate to high risks of unmasked large indoor gatherings, the relatively low risk of death, the moderate to high risks to those with other co-morbidities. What most people hear is “risk, risk, risk, risk, risk…”
Is it any wonder that many rebel against what they perceive as a constant bombardment of things that all seem to be dangerous? Here, too, they are missing the nuance that comes from the preceding word – “low,” “moderate,” or “high.” For many of us, the distinction between the scientific precision of “risk” is lost, and it’s simply used as another qualitative, subjective term like “safe.”
[1] Reported in a marvelous book called 100 Most Dangerous Things in Everyday Life by Laura Lee
