When did you stop using your baby monitor in the middle of the night?? How old wa your kid??

Ok my son has just turn one. his room door and mine make like an L. So anyway my mother n law and a few others have told me its time to stop using the baby monitor in the middle of the night. I don't use it in the day when he is napping because I leave his door open. And I sleep with the baby monitor inches from my ear. He can scream loud this I know. However, I don't really know if its time. I'm scared I'll sleep through him waking up and he'll be screaming forever before waking me up. OOO he sleep through the night now. He normal goes to bed between 8 and 10 and wakes up between 6:30 and 8 in the morning. Whats your advise???