It happens, lax safety on and off the field and poor gun safety/trigger control. Keep your mask on at all times on the field and barrel bags on off the field, and accidents like this can't happen (source: I ref and play paintball every weekend). We kick people off the field for lifting their mask when they are on the field and ensure barrel bags go on before walking back into the staging area.

Total accident. Many of us were all hanging out by the cars and one of the guns went off.

Gosh that's brutal. Sorry to hear it man, glad to hear you're above it both professional and spiritually.

I also feel bad for the person who's marker went off in your face. What a horrible guilt that must be.