Namahn

At a 1983 NATO conference, Professor Dr. Erik Hollnagel stated that the theory of human error was not a useful one. In this fascinating interview, he explains to Namahn why he still considers this theory to be flawed for the simple reason that human error is unintentional, otherwise errors would be something people wanted and planned to do and would therefore be preventable.

Hollnagel argues that the focus of risk analysis should be normal human performance, suggesting that accidents occur as a consequence of a series of trade-offs we make between efficiency and thoroughness, coined by him as the ETTO (Efficiency Thoroughness Trade-off) principle. These trade-offs are not random; they are regular, effective and learnt. Hollnagel believes if we study this variability of normal performance and discover under which conditions it combines in unwanted ways, we could then build in preventions.

Hollnagel goes on to discuss with Namahn the challenges our complex and intertwined social technical systems pose, using the present financial crisis as an example of a system many people do not understand, and yet we try to control it in a very simple way: the interest rate. "It's like having just one dial for a complex system, and not knowing how the dial works. In the US they've turned the dial completely to 0%. What if this doesn't work? They don’t have a model explaining the effect it will have, it’s a physiological response, one to make people feel better."

So, does this make it an irrational response? Hollnagel considers rationality to an artifact of logic. In Western cultures, we've separated 'cool' (rational) cognition from 'hot' (emotive) cognition and effectively pushed the latter aside. Hollnagel argues that we can't separate the two because we use them both. People try to accomplish tasks through tried and tested short cuts and their general knowledge of the world and not through rationality: the ETTO principle.

When Namahn asks Hollnagel whether his work makes him more safety conscious he admits that when he climbs a ladder and something is out of reach, there are two things he can do: stretch out to reach it or climb down and move the ladder. "Ten years ago I stretched out; today I move the ladder. I've learnt it's worth the effort."