Micromorts and microlives

How do you effectively communicate risk when something is risky over the medium or long term? Measure the risk in micromorts (the one-in-a-million chance of dying) and microlives (half an hour of extra life).

So, for example, skydiving will set you back 8 micromorts. In other words, each skydive has roughly an 8-in-a-million chance of killing you. Running a marathon? That’s 7 micromorts. Giving birth? 120 micromorts, or 170 if by C-section. I wonder if that would change our attitude to women’s health, if we pointed out that it’s just as risky to give birth as it is to go skydiving fifteen times in a row?

Related to this concept is the microlife: a unit of measurement that represents half an hour of life expectancy. Lose a microlife, and you will on average die half an hour earlier. Gain a microlife, you’re living a half hour longer. Watching television for two hours? You just lost a microlife. Eat five servings of fruit and vegetables? You gained four microlives (if you’re a man) or three microlives (if you’re a woman).

So, how much is a micromort worth? A 2009 study attempted to put a dollar figure on the micromort: how much money would people accept to take a one-in-a-million risk? $50, as it turns out.

• Micromort
• Microlife