Do I have to wear eye protection?

Under the World Squash Singles Rules (Appendix 4):

• Protective eyewear is mandatory for all doubles and junior events sanctioned by the World Squash Federation.
• For everyone else it is recommended: World Squash recommends all players wear eyewear made to an appropriate national standard, properly over the eyes at all times during play, including the warm-up, whether social, league or tournament.
• It's the player's responsibility to make sure the eyewear is fit for purpose. World Squash publishes a list of certified eyewear at worldsquash.sport/eyewear.

If your glasses or eyewear are damaged or a contact lens comes out, you get up to 2 minutes to sort it out (Rule 7.3).

An event's own competition rules can also make eyewear compulsory.