How to avoid getting sick at college

In the dorm room

Your college roommate is the most likely source of catching a cold, flu, COVID, and RSV. (Keep reading for tips on how to avoid picking up an illness in the cafeteria or lecture hall.)

You're sharing under-ventilated or even unventilated air with your roommate 8-18 hours a day, depending on how much time you spend in your dorm. And that shared space is probably approximately 230 square feet. If you're reading this, you're intelligent and conscientious enough to know not to share your roommate's water bottle or cup. But pause and think about how much you're rebreathing their exhalations. (a lot) As carbon dioxide levels creep higher, the amount of air you're rebreathing from your own and your roommate's exhalations also increases. 1500 ppm of CO2 is common in an underventilated room, and it can get above 2,000 ppm overnight. That's more than 3% of rebreathed air, according to Rebreathed Fraction of Air by David Elfstrom.

So what can you do?

* Open a window when weather permits and point a fan blowing out toward the open window to increase oxygen and decrease carbon dioxide (invest in a fly swatter)

* Crack a window when the temperature is cold and marvel at the beauty of thermodynamics that causes warm air from your dorm to be quickly sucked out the tiny crack and into the cold air outside, bringing CO2 along with it

* Run a quiet air purifier next to your bed. A Luggable 5-Fan is compact enough for a dorm desk or bedside, clears a room that size in minutes on its whisper-quiet setting, and costs about £2 a year to run. If you and your roommate each keep one going, you dramatically cut how much of each other's exhaled air you rebreathe. Cross-table studies show how powerful room filtration is at quickly clearing each person's exhalations.

* Don't count on a purifier for white noise. Even our loudest unit, the Luggable XL Ultra, runs at about 39 dBA of sound pressure, and on its quiet setting a Luggable is under 35 dB, so it won't drown out a snoring roommate but it also won't disturb your sleep or study.

Attending classes

In lecture halls and shared classrooms, your best protection is a well-fitted KN95 or N95 mask, plus choosing a seat near a fresh-air vent or a cracked window where you can. Keep your Luggable running back in your room so you come home to clean air between classes.

In the dining hall

When you have to take your mask off to eat, pick a quieter, less crowded spot, an empty corner of campus or an off-peak cafeteria slot, and sit near a window or vent where you can. Back in your room, a Luggable 5-Fan keeps your personal space consistently clean.