My boa keeps bitn me,i neva feed him in is tank,i handle im everyday.ive had him 4 over 2 yrs!?

I had a six foot columbian red tailed boa named "dan" I never fed him anything live I was told not to because they are pretty docile. I never had any problems .......However when I took him out side and someone made a noise to startle him he bit me go figure it was only a superficial bite though it was NEVER anything very severe. I dont know what ta tell you sounds like you are doing everything right maybe try feeding him more often could be he is in a bad mood cuz he is hungry