The FA have created the following guidance on using 3G pitches in hot weather. The guidance is to be used on the rare occasion that match officials, managers or players feel that the temperature of a 3G pitch is excessively hot.
Using 3g pitches in hot weather guide
The NSPCC have also provided guidance on what considerations should be made if you are planning on participating in a sporting event.
SAFEGUARDING AT EVENTS - WEATHER CONSIDERATIONS