2- How do you enter a Level 4 lab area? What are the requirements compared to Level 2?

Level Four, like Levels Two and Three is kept at negative air pressure to contain leaks if necessary. The room is ensconced in thick glass. Leve 4, also requires specific attire, a biohazard space suit. Scrub suits are worn under the space suit, and surgical gloves are taped to the sleeves. The space suits themselves are pressurized, heavy duty, and made from sturdy plastic. The suit's gloves were made of brown rubber.