It depends on the rules of the field you play at. I've seen some say at least 13, others say 10, all of them require waivers for under 18 and full face protection masks.
Under 18 you have to do a bunch of paperwork and have a full face mask. Over 18 you ONLY need eye protection.
It depends on the field, however, for MIR events, I've seen people around the age of 9-12. I myself started around the age of 14, and had no problems.
I think most places, if you are under 18 you need a parents waiver. The youngest I've seen looked to be 10-12.
Little kids can play, they just need a full face mask
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