<http://www.newscientist.com/dailynews/news.jsp?id=ns9999426> Eye test A Bladerunner-style eye scan reveals if you are too drunk, stoned or tired to work
A new 90 second eye test could soon be used by companies to see if employees are too drunk, drugged or tired to do their job properly.
Much like the eye test in the movie Blade Runner, used to determine whether subjects are androids, subjects of the new test are asked to perform certain tasks during the examination.
But rather than being asked psychological questions, subjects are simply asked to follow a dot with their eye as it moves back and forth in a set pattern.
The test does not distinguish between different causes of impairment, says Charles Phillips, President of Eye Dynamics of Torrence, California, who developed SafetyScope. "It simply gives a single reading - yes or no". The company claims the test is 97 per cent effective.
Oscillating eyes
Twenty different parameters are measured during the test, relating to the position and reaction time of the eye and the size of pupil.
Even in healthy subjects the eyeball exhibits rapid, involuntary, oscillatory movements, a phenomenon called nystagmus. But as the subject's brain function becomes increasingly impaired these movements become more and more erratic.
SafetyScope uses an algorithm developed through thousands of trials with hundreds of people under the influence of heroin, marijuana, alcohol and exhaustion. The trials to compared their current reading with a baseline reading taken when they were first employed to determine whether or not that person was fit for work.
One of the advantages of SafetyScope, says Phillips, is that unlike blood and urine tests which only measure the presence of a substance in the body, the eye test takes into account the physiological effects of the substance.
"Invasion of privacy"
But some unions are less than happy about the development. An American Civil Liberties Union spokesman pointed out that even urine tests can be faulty and give inaccurate readings. Moreover the whole notion of testing employees is an invasion of privacy.
But Phillips believes it doesn't have to be. "We don't want to know if someone smoked some marijuana at a party over the weekend," says Phillips. "We just want to know if someone is fit for duty."
The system is now being tried out by the Louisiana Labour Station, an organisation that provides temporary labour to the petrochemical industry, testing people before they are sent out on jobs.
Phillips says his ultimate vindication would be to see the airline industry adopting SafetyScope, but he isn't holding his breath. If they started using it, it could be seen as an admission that a problem exists - it's a political mountain, he says.
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