Yeah, at least he asked. Most just go out and start blasting people who are 15 - 20m away. Still very worrying though ?
My local site has a clearly marked 30m target on the range which also has "MED" painted onto it under the "30m". I think that's a good way to do it, as everyone has to go through chrono, and chrono is done on the range where that target is, so everyone will see it. Or should see it. Airsofters can be really blind...