From that web-site:
"There are all kinds of remedies for dealing with this irritating phenomenon, some more effective than others. As a general rule, move your head as far away from the onion as you can, so the gas will mostly disperse before it reaches your eyes. If you really can't stand the tears, the simplest solution might be to wear goggles..."
Actually, there's a method I've tried that works very well: breathe in the smell deeply! It causes your eyes to water a lot right away, but after a few seconds, you're no longer bothered.