To do Up at The O2, you must:
be at least 8 years old
be at least 1.2m tall
not weigh more than 21 stone/130kg/286lbs
not have a waist measurement more than 125cm
not have an upper thigh measurement more than 75cm.
Remember that under 18s must be with an adult in the ratios as below:
8-17 years 1:5 ratio