This article is from the Table Tennis (Ping Pong) FAQ, by ttennis@bu.edu with numerous contributions by others.
3.7.3.1The age as of the first day of the tournament will determine
eligibility for all junior events in that tournament.
3.7.3.2The age as of the end of the calendar year will determine the
eligibility for all senior events in all tournaments during that
year.
3.7.3.3The tournament sponsor may demand at the tournament site proof
of age from anyone entering an age-limited event.
 
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