This includes decongestants or other medication that makes you drowsy. Come properly dressed for lab. You should wear an apron, smock, or old clothes to lab. Shoes should be comfortable, and long hair tied back. If chemicals enter the eye, they quickly migrate behind the lens, and cause eye damage before the lens can be removed.
Soft lenses have the additional disadvantage of being attacked by organic solvents.
If possible, wear regular prescription glasses. Also be sure to wash your hands thoroughly before removing goggles. There is absolutely no eating, drinking, or smoking allowed in the lab. You may leave lab for a break at any convenient time, after assuring that your experiment will be attended to by another student, and after notifying your instructor. Read, understand, and follow directions.